CA2663419C - Method and apparatus for mitigating oscillation between repeaters - Google Patents
Method and apparatus for mitigating oscillation between repeaters Download PDFInfo
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- CA2663419C CA2663419C CA2663419A CA2663419A CA2663419C CA 2663419 C CA2663419 C CA 2663419C CA 2663419 A CA2663419 A CA 2663419A CA 2663419 A CA2663419 A CA 2663419A CA 2663419 C CA2663419 C CA 2663419C
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Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B7/00—Radio transmission systems, i.e. using radiation field
- H04B7/14—Relay systems
- H04B7/15—Active relay systems
- H04B7/155—Ground-based stations
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B7/00—Radio transmission systems, i.e. using radiation field
- H04B7/14—Relay systems
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04W—WIRELESS COMMUNICATION NETWORKS
- H04W16/00—Network planning, e.g. coverage or traffic planning tools; Network deployment, e.g. resource partitioning or cells structures
- H04W16/24—Cell structures
- H04W16/26—Cell enhancers or enhancement, e.g. for tunnels, building shadow
Abstract
A first repeater operating within a wireless network including a second repeater capable of communicating with the first repeater, and first and second wireless station devices capable of communicating with at least one of the first repeater and the second repeater, includes a reception device for receiving a wireless signal at a reception frequency; a detector for detecting if a predetermined portion of the received wireless signal includes a modified portion to thereby determine that the received signal is from the second repeater; and a transmission device for transmitting the wireless signal to one of the first and second wireless station devices at a transmission frequency to thereby repeat the wireless signal.
Description
METHOD AND APPARATUS FOR MITIGATING OSCILLATION BETWEEN
REPEATERS
[0001] TECHNICAL FIELD
REPEATERS
[0001] TECHNICAL FIELD
[0002] The technical field relates generally to a repeater for a wireless communication network, and, more particularly, to a repeater configuration for reducing oscillations among two or more repeaters or repeater sections.
BACKGROUND
BACKGROUND
[0003] Conventionally, the coverage area of a wireless communication network such as, for example, a Time Division Duplex (TDD), Frequency Division Duplex (FDD) Wireless-Fidelity (Wi-Fi), Worldwide Interoperability for Microwave Access (Wi-max), Cellular, Global System for Mobile communications (GSM), Code Division Multiple Access (CDMA), or 3G based wireless network can be increased by a repeater.
=
Exemplary repeaters include, for example, frequency translating repeaters or same frequency repeaters which operate in the physical layer or data link layer as defined by the Open Systems Interconnection Basic Reference Model (OSI Model).
=
Exemplary repeaters include, for example, frequency translating repeaters or same frequency repeaters which operate in the physical layer or data link layer as defined by the Open Systems Interconnection Basic Reference Model (OSI Model).
[0004] Repeaters are also used to satisfy the increasing need to extend the range of nodes such as access points associated with wireless networks, including but not limited to wireless local area networks (WLANs) and wireless metropolitan area networks (WMANs) described and specified in the Institute of Electrical and Electronics Engineers (IEEE) 802.11, 802.16 and 802.20 standards due to the increasing popularity of unrestrained access to broadband services by, for example, portable computing devices.
The effective proliferation of wireless networks depends heavily on sustaining and increasing performance levels as user demands increase.
The effective proliferation of wireless networks depends heavily on sustaining and increasing performance levels as user demands increase.
[0005] However, when multiple repeaters occupy the same radio frequency environment, problems, such as, oscillation between repeaters can arise.
Oscillations can lead to a host of problems such as distortion, saturation, loss of synchronization, and data or information loss.
Oscillations can lead to a host of problems such as distortion, saturation, loss of synchronization, and data or information loss.
[0006] Further, the problem of "scalability" of many closely located repeaters must be addressed. For instance, when repeaters are deployed in close proximity in a multi-tenant dwelling, an effective coverage area may become so large as to cause a "flooding"
of packets. While the coverage area has been greatly enhanced, there may be inefficiency due to limited capacity for a large number of users.
of packets. While the coverage area has been greatly enhanced, there may be inefficiency due to limited capacity for a large number of users.
[0007] Therefore, there is a need for low cost and low risk solutions to such oscillation problems. Preferably, the solution will be extendible to allow for more capability than simply preventing multi-repeater oscillation.
SUMMARY
SUMMARY
[0008] In view of the above problems, a repeater operating in a wireless network according to various embodiments mitigates oscillation so that it will substantially not repeat a signal from another repeater in the wireless network in an oscillating state. The wireless network can include a second repeater capable of communicating with the first repeater, and first and second wireless station devices such as an access point and a wireless computing device capable of communicating with at least one of the first repeater and the second repeater.
[0009] According to various embodiments, the repeater includes a reception device for receiving a wireless signal at a reception frequency; a detector for detecting if a predetermined portion of the received wireless signal includes a modified portion to thereby determine that the received signal is from the second repeater; and a transmission device for transmitting the wireless signal to one of the first and second wireless station devices at a transmission frequency to thereby repeat the wireless signal.
[0010] If the predetermined portion of the received wireless signal includes the modified portion, the transmission device can be configured to not repeat a substantial portion of the wireless signal, to transmit the wireless signal at a frequency different from the transmission frequency, or transmit the wireless signal at a power level different from an original transmission power level.
[0011] The repeater can further include a signal modification device for modifying the wireless signal. The signal modification device can be, for example, a notch processor configured to insert a notch pattern on the wireless signal to be transmitted and to detect a notch pattern inserted on a wireless signal as the modified portion.
[0012] The signal modification device can also be, for example, a bi-phase modulation device configured to modulate a phase of the predetermined portion of the wireless signal. The bi-phase modulator can modulate the predetermined portion of the wireless signal to have a unique signature recognizable by the second repeater upon receiving the modified wireless signal. A surface acoustic wave (SAW) filter can be coupled to the output of the bi-phase modulator to remove spectral splattering from the modified wireless signal. A timing circuit can also be coupled to the bi-phase modulator for controlling an amount of time during which the bi-phase modulator modulates the phase of the predetermined portion of the wireless signal.
[0013] The bi-phase modulator can includes a transfer switch coupled to an input of a linear oscillator (LO), the transfer switch switching positive and negative inputs of the LO at a predetermined frequency to modulate the phase of the predetermined portion of the wireless signal.
[0014] The repeater can further include a de-modification device such as a demodulation device for removing the modified portion from the predetermined portion of the wireless signal.
[0015] The transmission device is configured to transmit or not transmit the wireless signal if the predetermined portion of the received wireless signal includes the modified portion.
[0016] The predetermined portion of the received wireless signal can be a preamble of the wireless signal and the modified portion can be a predetermined phase variation.
[0017] The detector can further be configured to detect if the wireless signal was transmitted from one of the first and second wireless station devices by performing a qualifying detection process on the received wireless signal. The qualifying detection process can include correlating a preamble of the received wireless signal to a predetermined signal pattern or demodulating one of a predetermined information sequence, a pilot channel and a pilot carrier.
[0018] The repeater can be one of a frequency translating repeater in which the reception frequency and transmission frequency are different, and a same frequency repeater in which the reception frequency and transmission frequency are same.
[0019] The repeater can also include a processor and a memory coupled to the processor. A power adjustment routine for configuring the CPU can be stored in the memory. The processor can be configured to: generate probe packets to be transmitted to the second repeater at the transmission frequency; measure a received signal strength indication (RSSI) of a packet received in response to the probe packets;
determine if a path loss defined by a difference between a power level at which the probe packets were transmitted and the measured RSSI is less than a predetermined value; and mark the transmission frequency as unavailable for use if the path loss is less than the predetermined value.
determine if a path loss defined by a difference between a power level at which the probe packets were transmitted and the measured RSSI is less than a predetermined value; and mark the transmission frequency as unavailable for use if the path loss is less than the predetermined value.
[0020] The processor can further be configured to: generate a group of packets to be transmitted to the second repeater at the transmission frequency if the path loss is not less than approximately 80 dB; determine an average RSSI for the group of packets;
and if the average RSSI is less than a predetermined level, mark a current transmission power as acceptable.
and if the average RSSI is less than a predetermined level, mark a current transmission power as acceptable.
[0021] The processor can further be configured to: adjust the current transmission power downward by a predetermined decibel level if the average RSSI is less not than the predetermined level; regenerate the group of packets to be transmitted to the second repeater at the transmission frequency; determine an average RSSI for the group of packets; and if the average RSSI is less than a predetermined level, mark a current transmission power as acceptable.
[0022] Additional detection capability included in the repeaters can enable detection of the preamble with the phase modulated sequence and additional communications. For instance, it may be desired that packets from some repeaters may be re-repeated, while those from other repeaters are not repeated. Another example would be that only packets with a specific signature are allowed to be repeated and all others are filtered off.
Other actions may include placing packets with a unique signature on a unique repeated frequency, and as such the signature may act as an addressing function, a quality of service code, or a priority code.
[0022a] According to an aspect of the present invention, there is provided a first repeater operating within a wireless network, the wireless network including a second repeater capable of communicating with the first repeater, and first and second wireless station devices capable of communicating with at least one of the first repeater and the second repeater, the first repeater comprising: a reception device for receiving a wireless signal at a reception frequency; a detector for detecting if a predetermined portion of the received wireless signal includes a modified portion to thereby determine that the received signal is from the second repeater; and a transmission device for transmitting the wireless signal to one of the first and second wireless station devices at a transmission frequency to thereby repeat the wireless signal, wherein the repeater further comprises: a processor; and a memory coupled to the processor, the memory for storing a power adjustment routine for configuring the processor;
wherein the processor is configured to: generate probe packets to be transmitted to the second repeater at the transmission frequency; measure a received signal strength indication (RSSI) of a packet received in response to the probe packets; determine if a path loss defined by a difference between a power level at which the probe packets were transmitted and the measured RSSI is less than a predetermined value; and mark the transmission frequency as unavailable for use if the path loss is less than the predetermined value.
[0022b] According to another aspect of the present invention, there is provided a first repeater operating within a wireless network, the wireless network including a second repeater capable of communicating with the first repeater, and first and second wireless stations capable of communicating with at least one of the first repeater and the second repeater, the first repeater comprising: a reception device receiving a wireless signal from one of the second repeater, first wireless station, and second wireless station; a detection device coupled to the reception device, the detection device detecting if a received signal strength indication (RSSI) of the wireless signal is greater than a predetermined RSSI threshold;
a digital demodulator coupled to the reception device, the digital demodulator configured to demodulate the wireless signal if the detected RSSI is greater than the predetermined RSSI
threshold; a signal modification device coupled to the reception device, the signal modification device configured to modify a predetermined portion of the wireless signal; and a transmission device coupled to the signal modification device for transmitting the modified wireless signal to one of the second repeater, first wireless station, and second wireless station; wherein the signal modification device includes a bi-phase modulation device configured to modulate a phase of the predetermined portion of the wireless signal, and wherein the hi-phase modulator includes a transfer switch coupled to a linear oscillator (LO), the transfer switch switching positive and negative terminals of the LO at a predetermined frequency to modulate the phase of the predetermined portion of the wireless signal.
[0022c] According to still another aspect of the present invention, there is provided a first repeater operating within a wireless network, the wireless network including a second repeater capable of communicating with the first repeater, and first and second wireless stations capable of communicating with at least one of the first repeater and the second repeater, the first repeater comprising: a reception device receiving a wireless signal including one or more packets at a reception frequency; a signal modification and detection device coupled to the reception device, the signal modification and detection device configured to modify a predetermined portion of the packet to thereby generate a modified wireless signal and to detect if a predetermined portion of the packet includes a modified signal pattern; a transmission device coupled to the signal modification and detection device for transmitting the modified wireless signal to one of the second repeater, first wireless 6a station, and second wireless station at a predetermined power level and a transmission frequency; a processor controlling the reception device and the transmission device; and a memory coupled to the processor, the memory for storing a power adjustment routine for configuring the processor to: generate probe packets to be transmitted to the second repeater at the transmission frequency; measure a received signal strength indication (RSSI) of a packet received in response to the probe packets; and adjust one of the power level or the transmission frequency in accordance with the measured RSSI.
[0022d] According to a further aspect of the present invention, there is provided a repeater operating within a wireless network, comprising: a reception device configured to receive a wireless signal; a detector configured to detect whether a received signal strength indication (RSSI) of the received wireless signal is greater than a predetermined threshold; a digital demodulator configured to demodulate the wireless signal if the detected RSSI is greater than the predetermined threshold; a signal modification device configured to modify a first few symbols of packets in a predetermined portion of the received wireless signal; and a transmission device configured to transmit the modified wireless signal to one or more of another repeater or a wireless station device, wherein the signal modification device includes a bi-phase modulator configured to modulate a phase of the first few symbols of packets in the predetermined portion of the wireless signal, further comprising a timing circuit coupled to the bi-phase modulator, the timing circuit configured to control an amount of time during which the bi-phase modulator modulates the phase of the first few symbols of packets in the predetermined portion of the wireless signal, the timing circuit being activated when the detected RSSI is greater than the predetermined threshold.
BRIEF DESCRIPTION OF THE DRAWINGS
Other actions may include placing packets with a unique signature on a unique repeated frequency, and as such the signature may act as an addressing function, a quality of service code, or a priority code.
[0022a] According to an aspect of the present invention, there is provided a first repeater operating within a wireless network, the wireless network including a second repeater capable of communicating with the first repeater, and first and second wireless station devices capable of communicating with at least one of the first repeater and the second repeater, the first repeater comprising: a reception device for receiving a wireless signal at a reception frequency; a detector for detecting if a predetermined portion of the received wireless signal includes a modified portion to thereby determine that the received signal is from the second repeater; and a transmission device for transmitting the wireless signal to one of the first and second wireless station devices at a transmission frequency to thereby repeat the wireless signal, wherein the repeater further comprises: a processor; and a memory coupled to the processor, the memory for storing a power adjustment routine for configuring the processor;
wherein the processor is configured to: generate probe packets to be transmitted to the second repeater at the transmission frequency; measure a received signal strength indication (RSSI) of a packet received in response to the probe packets; determine if a path loss defined by a difference between a power level at which the probe packets were transmitted and the measured RSSI is less than a predetermined value; and mark the transmission frequency as unavailable for use if the path loss is less than the predetermined value.
[0022b] According to another aspect of the present invention, there is provided a first repeater operating within a wireless network, the wireless network including a second repeater capable of communicating with the first repeater, and first and second wireless stations capable of communicating with at least one of the first repeater and the second repeater, the first repeater comprising: a reception device receiving a wireless signal from one of the second repeater, first wireless station, and second wireless station; a detection device coupled to the reception device, the detection device detecting if a received signal strength indication (RSSI) of the wireless signal is greater than a predetermined RSSI threshold;
a digital demodulator coupled to the reception device, the digital demodulator configured to demodulate the wireless signal if the detected RSSI is greater than the predetermined RSSI
threshold; a signal modification device coupled to the reception device, the signal modification device configured to modify a predetermined portion of the wireless signal; and a transmission device coupled to the signal modification device for transmitting the modified wireless signal to one of the second repeater, first wireless station, and second wireless station; wherein the signal modification device includes a bi-phase modulation device configured to modulate a phase of the predetermined portion of the wireless signal, and wherein the hi-phase modulator includes a transfer switch coupled to a linear oscillator (LO), the transfer switch switching positive and negative terminals of the LO at a predetermined frequency to modulate the phase of the predetermined portion of the wireless signal.
[0022c] According to still another aspect of the present invention, there is provided a first repeater operating within a wireless network, the wireless network including a second repeater capable of communicating with the first repeater, and first and second wireless stations capable of communicating with at least one of the first repeater and the second repeater, the first repeater comprising: a reception device receiving a wireless signal including one or more packets at a reception frequency; a signal modification and detection device coupled to the reception device, the signal modification and detection device configured to modify a predetermined portion of the packet to thereby generate a modified wireless signal and to detect if a predetermined portion of the packet includes a modified signal pattern; a transmission device coupled to the signal modification and detection device for transmitting the modified wireless signal to one of the second repeater, first wireless 6a station, and second wireless station at a predetermined power level and a transmission frequency; a processor controlling the reception device and the transmission device; and a memory coupled to the processor, the memory for storing a power adjustment routine for configuring the processor to: generate probe packets to be transmitted to the second repeater at the transmission frequency; measure a received signal strength indication (RSSI) of a packet received in response to the probe packets; and adjust one of the power level or the transmission frequency in accordance with the measured RSSI.
[0022d] According to a further aspect of the present invention, there is provided a repeater operating within a wireless network, comprising: a reception device configured to receive a wireless signal; a detector configured to detect whether a received signal strength indication (RSSI) of the received wireless signal is greater than a predetermined threshold; a digital demodulator configured to demodulate the wireless signal if the detected RSSI is greater than the predetermined threshold; a signal modification device configured to modify a first few symbols of packets in a predetermined portion of the received wireless signal; and a transmission device configured to transmit the modified wireless signal to one or more of another repeater or a wireless station device, wherein the signal modification device includes a bi-phase modulator configured to modulate a phase of the first few symbols of packets in the predetermined portion of the wireless signal, further comprising a timing circuit coupled to the bi-phase modulator, the timing circuit configured to control an amount of time during which the bi-phase modulator modulates the phase of the first few symbols of packets in the predetermined portion of the wireless signal, the timing circuit being activated when the detected RSSI is greater than the predetermined threshold.
BRIEF DESCRIPTION OF THE DRAWINGS
[0023] The accompanying figures, where like reference numerals refer to identical or functionally similar elements throughout the separate views and which together with the detailed description below are incorporated in and form part of the specification, serve to further illustrate various embodiments and to explain various principles and advantages in accordance with the present invention.
6b
6b
[0024] FIGs. IA - 1B are an illustration of a test configuration and a screen capture illustrating test results associated with an exemplary repeater direct sequence spread spectrum (DSSS) configuration with no phase modulation and WLAN only enabled.
6c
6c
[0025] FIGs. 2A - 2B are an illustration of a test configuration and a screen capture illustrating test results associated with an exemplary repeater DSSS
configuration with phase modulation and WLAN only enabled.
configuration with phase modulation and WLAN only enabled.
[0026] FIGs. 3A - 3B are an illustration of a test configuration and a screen capture illustrating test results associated with an exemplary repeater DSSS
configuration with phase modulation and WLAN only disenabled.
configuration with phase modulation and WLAN only disenabled.
[0027] FIGs. 4A - 4B are an illustration of a test configuration and a screen capture further illustrating the test results associated with an exemplary repeater DSSS
configuration of FIG. 3 with phase modulation and WLAN only disenabled.
configuration of FIG. 3 with phase modulation and WLAN only disenabled.
[0028] FIGs. 5A - 5B are an illustration of a test configuration and a screen capture illustrating test results associated with an exemplary repeater orthogonal frequency division multiplexed (OFDM) configuration with no phase modulation and WLAN
only enabled.
only enabled.
[0029] FIGs. 6A - 6B are an illustration of a test configuration and a screen capture illustrating test results associated with an exemplary repeater OFDM
configuration with phase modulation and WLAN only enabled.
configuration with phase modulation and WLAN only enabled.
[0030] FIGs. 7A - 7B are an illustration of a test configuration and a screen capture illustrating test results associated with an exemplary repeater OFDM
configuration with phase modulation and WLAN only disenabled.
configuration with phase modulation and WLAN only disenabled.
[0031] FIGs. 8A - 8B are an illustration of a test configuration and a spectrum analyzer capture illustrating a signal generator output with no phase modulation.
[0032] FIGs. 9A - 9B are an illustration of a test configuration and a spectrum analyzer capture illustrating a signal generator OFDM output with phase modulation.
[0033] FIGs. 10A - 10B are an illustration of a test configuration and a spectrum analyzer capture illustrating a signal generator OFDM output with phase modulation and low loss surface acoustic wave (SAW) filter.
[0034] FIGs. 11A - 11B are an illustration of a test configuration and a spectrum analyzer capture illustrating a signal generator OFDM output with phase modulation and low loss SAW filter and high reject SAW filter.
[0035] FIGs. 12A - 12B are an illustration of a test configuration and a spectrum analyzer capture illustrating a signal generator DSSS output with no phase modulation.
[0036] FIGs. 13A - 13B are an illustration of a test configuration and a spectrum analyzer capture illustrating a signal generator DSSS output with phase modulation.
[0037] FIGs. 14A - 14B are an illustration of a test configuration and a spectrum analyzer capture illustrating a signal generator DSSS output with phase modulation and a low loss SAW filter.
[0038] FIGs. 15A - 15B are an illustration of a test configuration and a spectrum analyzer capture illustrating a signal generator DSSS output with phase modulation, a low loss SAW filter and a high reject SAW filter.
[0039] FIG. 16 is a block diagram illustrating an exemplary wireless network environment including two exemplary repeaters.
[0040] FIG. 17 is a connection diagram illustrating potential connections which may be established between exemplary repeaters, an AP and mobile communication station in a WLAN.
[0041] FIG. 18A is a schematic drawing illustrating an exemplary repeater in accordance with an exemplary embodiment.
[0042] FIG. 18B is a schematic drawing illustrating an exemplary repeater in accordance with another exemplary embodiment.
[0043] FIG. 19 is an exemplary circuit diagram of a timing circuit.
[0044] FIG. 20 is an exemplary circuit diagram of a bi-phase modulator.
[0045] FIG. 21 is a block diagram of an exemplary notch processor.
[0046] FIG. 22 is an illustration of exemplary notch insertion parameters.
[0047] FIG. 23 is a flow diagram illustrating an exemplary notch detection signal processing.
[0048] FIG. 24 is a flow diagram illustrating an exemplary power adjustment routine for mitigating oscillation.
DETAILED DESCRIPTION
DETAILED DESCRIPTION
[0049] In overview, the present disclosure concerns a repeater configuration for mitigating oscillation. The instant disclosure is provided to further explain in an enabling fashion the best modes of performing one or more embodiments of the present invention.
The use of relational terms such as first and second, and the like, if any, are used solely to distinguish one from another entity, item, or action without necessarily requiring or implying any actual such relationship or order between such entities, items or actions. It is noted that some embodiments may include a plurality of processes or steps, which can be performed in any order, unless expressly and necessarily limited to a particular order;
i.e., processes or steps that are not so limited may be performed in any order.
The use of relational terms such as first and second, and the like, if any, are used solely to distinguish one from another entity, item, or action without necessarily requiring or implying any actual such relationship or order between such entities, items or actions. It is noted that some embodiments may include a plurality of processes or steps, which can be performed in any order, unless expressly and necessarily limited to a particular order;
i.e., processes or steps that are not so limited may be performed in any order.
[0050] Much of the inventive functionality and many of the inventive principles when implemented, are best supported with or in computer instructions (software) or integrated circuits (ICs), and/or application specific ICs. It is expected that one of ordinary skill, notwithstanding possibly significant effort and many design choices motivated by, for example, available time, current technology, and economic considerations, when guided by the concepts and principles disclosed herein will be readily capable of generating such software instructions or ICs with minimal experimentation. Therefore, in the interest of brevity and minimization of any risk of obscuring the principles and concepts according to the present invention, further discussion of such software and ICs, if any, will be limited to the essentials with respect to the principles and concepts used by the exemplary embodiments.
[0051] Referring now to FIG. 16, a wide area connection 101, which could be, for example, an Ethernet connection, a Ti line, a wideband wireless connection or any other =
electrical connection providing a data communications path, may be connected to a wireless gateway, or access point (AP) 100. The wireless gateway 100 sends RF
signals, such as, for example, IEEE 802.11 packets or signals based upon Bluetooth, HyperIan, or other wireless communication protocols, to client units 104, 105, which may be personal computers, personal digital assistants, or any other devices capable of communicating with other like devices through one of the above mentioned wireless protocols.
A
wireless gateway, AP, or client device will be referred to here as a wireless station.
Respective propagation, or RF, paths to each of the client units 104, 105 are shown as 102, 103.
electrical connection providing a data communications path, may be connected to a wireless gateway, or access point (AP) 100. The wireless gateway 100 sends RF
signals, such as, for example, IEEE 802.11 packets or signals based upon Bluetooth, HyperIan, or other wireless communication protocols, to client units 104, 105, which may be personal computers, personal digital assistants, or any other devices capable of communicating with other like devices through one of the above mentioned wireless protocols.
A
wireless gateway, AP, or client device will be referred to here as a wireless station.
Respective propagation, or RF, paths to each of the client units 104, 105 are shown as 102, 103.
[0052] While the signal carried over RF path 102 is of sufficient strength to maintain high-speed data packet communications between the client unit 104 and the wireless gateway 100, the signals carried over the RF path 103 and intended for the client unit 105 would be attenuated when passing through a structural barrier such as walls 106 or 107 to a point where few, if any, data packets are received in either direction if not for wireless repeaters 200, 204.
[0053] To enhance the coverage and/or communication data rate to the client unit 105, wireless repeaters 200, 204 receive packets transmitted on an initial frequency channel 201 from the wireless gateway 100, access point or another repeater.
The wireless repeater 200 detects the presence of a packet on the first frequency channel 201 and receives the packet and re-transmits the packet with more power on a second frequency channel 202. Similarly, the wireless repeater 204 detects the presence of the packet on the second frequency channel 202, receives the packet and re-transmits the packet with more power on a third frequency channel 203. Unlike conventional WLAN
operating protocols, the client unit 105 operates on the third frequency channel, even though the wireless gateway 100 operates on the first frequency channel 203.
To perform the return packet operation, the wireless repeater 204 detects the presence of a transmitted packet on the third frequency channel 203 from the client unit 105, receives the packet on the third frequency channel 203, and re-transmits the packet on the second frequency channel 202. The wireless repeater 200 detects the presence of a transmitted packet on the second frequency channel 202 from wireless repeater 204, receives the packet on the second frequency channel 202, and re-transmits the packet on the first frequency channel 201. The wireless gateway 100 then receives the packet on the first frequency channel 201. In this way, the wireless repeaters 200, 204 are capable of simultaneously receiving and transmitting signals as well as extending the coverage and performance of the wireless gateway 100 to the client unit 105. When many units are isolated from one another, the repeaters 200, 204 can further act as a wireless bridge allowing two different groups of units to communicate where optimum RF propagation and coverage or, in many cases, any RF propagation and coverage was not previously possible.
The wireless repeater 200 detects the presence of a packet on the first frequency channel 201 and receives the packet and re-transmits the packet with more power on a second frequency channel 202. Similarly, the wireless repeater 204 detects the presence of the packet on the second frequency channel 202, receives the packet and re-transmits the packet with more power on a third frequency channel 203. Unlike conventional WLAN
operating protocols, the client unit 105 operates on the third frequency channel, even though the wireless gateway 100 operates on the first frequency channel 203.
To perform the return packet operation, the wireless repeater 204 detects the presence of a transmitted packet on the third frequency channel 203 from the client unit 105, receives the packet on the third frequency channel 203, and re-transmits the packet on the second frequency channel 202. The wireless repeater 200 detects the presence of a transmitted packet on the second frequency channel 202 from wireless repeater 204, receives the packet on the second frequency channel 202, and re-transmits the packet on the first frequency channel 201. The wireless gateway 100 then receives the packet on the first frequency channel 201. In this way, the wireless repeaters 200, 204 are capable of simultaneously receiving and transmitting signals as well as extending the coverage and performance of the wireless gateway 100 to the client unit 105. When many units are isolated from one another, the repeaters 200, 204 can further act as a wireless bridge allowing two different groups of units to communicate where optimum RF propagation and coverage or, in many cases, any RF propagation and coverage was not previously possible.
[0054] However, as described herein above, repeater systems using frequency translation may encounter problems, for example, when beacon signals are used.
Accordingly, range extension may be realized in such systems using repeaters for wireless local area networks and may be particularly advantageous when specific protocols are used, such as, for example, the 802.11 series of protocols by modifying the beacon signal to reflect the frequency translation. As noted however problems arise when adjacent nodes using or re-using translated frequencies within range of each other may establish false connections which lead to problems from node to node in terms of data traffic integrity. False connections may also lead to repeater to repeater oscillations when both repeaters are using the same frequency pairs and may further lead to system problems causing a general failure in the WLAN environment. The problems also arise on same frequency repeaters.
Accordingly, range extension may be realized in such systems using repeaters for wireless local area networks and may be particularly advantageous when specific protocols are used, such as, for example, the 802.11 series of protocols by modifying the beacon signal to reflect the frequency translation. As noted however problems arise when adjacent nodes using or re-using translated frequencies within range of each other may establish false connections which lead to problems from node to node in terms of data traffic integrity. False connections may also lead to repeater to repeater oscillations when both repeaters are using the same frequency pairs and may further lead to system problems causing a general failure in the WLAN environment. The problems also arise on same frequency repeaters.
[0055] Wireless repeaters 200, 204 convert packets from an initial frequency channel to a different frequency channel, where it may be received by one or more clients, such as station devices (STA) or client units 104 or 105, or a different repeater.
Client units 104 or 105 preferably receive a beacon identifying an 802.11b channel as being the appropriate channel for communication, and would receive information packets translated by the repeater 200, 204 from a first channel to a second channel.
Client units 104 or 105 preferably receive a beacon identifying an 802.11b channel as being the appropriate channel for communication, and would receive information packets translated by the repeater 200, 204 from a first channel to a second channel.
[0056] A problematic repeater condition may arise however, in exemplary scenario 300, as illustrated FIG. 17, wherein two repeaters R1 320 and R2 330 are configured to service one AP 310 which is within the transmit range of both repeaters via, for example, wireless connections 301 and 303. Repeaters R1 320 and R2 330 may further be capable of listening to each other's respective transmissions via a connection established over, for example, link 302. In exemplary scenario 300, the only connection established to communication unit or station device or STA 340 is connection 304 which as will be appreciated is a wireless or RF link. Problems arise when repeaters R1 320 and are operating on the same pair of channels, such as AP and repeater channels.
When AP
310 transmits, both R1 320 and R2 330 detect the transmission on, for example, a first frequency Fl and retransmit on a second frequency F2, such as the repeater channel. The primary problems arise when an isolated client station STA 340 transmits on F2 which, as describe above, is the repeater channel. R2 330 then repeats the transmission on Fl to AP 310. R1 320 detects the transmissions from R2 330 on Fl and tries to retransmit the detected transmissions. If R1 320 happens to select F2 as the transmit frequency, a loop will be established between R1 320 and R2 330. With sufficient gain, the RF
loop may oscillate, via, for example, positive feedback causing any signals destined for STA 340 over connection 304 to be jammed. It should be noted that the above RF loop does not occur if both repeaters detect the signal on the Fl because once they detect a signal on Fl they disable their receivers on F2 and then start repeating on F2.
When AP
310 transmits, both R1 320 and R2 330 detect the transmission on, for example, a first frequency Fl and retransmit on a second frequency F2, such as the repeater channel. The primary problems arise when an isolated client station STA 340 transmits on F2 which, as describe above, is the repeater channel. R2 330 then repeats the transmission on Fl to AP 310. R1 320 detects the transmissions from R2 330 on Fl and tries to retransmit the detected transmissions. If R1 320 happens to select F2 as the transmit frequency, a loop will be established between R1 320 and R2 330. With sufficient gain, the RF
loop may oscillate, via, for example, positive feedback causing any signals destined for STA 340 over connection 304 to be jammed. It should be noted that the above RF loop does not occur if both repeaters detect the signal on the Fl because once they detect a signal on Fl they disable their receivers on F2 and then start repeating on F2.
[0057] Referring to FIG. 18A, a repeater 1800 for mitigating the above-described oscillation according to a first embodiment will be described. The repeater may be, for example, a frequency translating repeater as discussed above or a same-frequency repeater. The repeater 1800 includes first and second antennas (ANTA, ANT B) serving as reception and transmission devices for receiving and transmitting signals on first and second channels. A signal received via one of the first antenna ANTA or second antenna ANTB is processed by processing elements such as a low noise amplifier (LNA), image reject filter (IRF), field effect transistor (FET) mixer, surface acoustic wave (SAW) filters, amplifier, is split and propagated on two different signals paths by, for example, splitter 1816. One of the split signal paths from the splitter 1816 is preferably coupled to a logarithmic amplifier 1820 via an amplifier and the other split signal path is preferably coupled to an adjustable gain control (AGC) element 1822 for adjusting the gain of the signal. A first output of the logarithmic amplifier 1820, which is preferably a signal representative of the amplitude envelope of the received signal strength indication (RSSI), is fed to a control portion of the AGC element 1822 for adjusting the gain control, to a processor 1825 and to a comparator 1823 for comparing the RSSI
level of the signal with a predetermined RSSI threshold received from the processor 1825. A
second output of logarithmic amplifier 1820 is fed to a digital demodulator 1824 via various digital elements for performing direct-sequence spread spectrum (DSSS) or orthogonal frequency-division multiplexing (OFDM) detection and demodulation, and internal packet generation. The digital demodulator 1824 can perform such detection by, for example, analyzing preamble information specific to DSSS and OFDM WLAN
packets generally located in the first few symbols of a packet, such as an 802.11 packet.
The digital demodulator 1824 or the repeater entirely can be placed in a WLAN
only configuration by, for example, the processor 1825.
level of the signal with a predetermined RSSI threshold received from the processor 1825. A
second output of logarithmic amplifier 1820 is fed to a digital demodulator 1824 via various digital elements for performing direct-sequence spread spectrum (DSSS) or orthogonal frequency-division multiplexing (OFDM) detection and demodulation, and internal packet generation. The digital demodulator 1824 can perform such detection by, for example, analyzing preamble information specific to DSSS and OFDM WLAN
packets generally located in the first few symbols of a packet, such as an 802.11 packet.
The digital demodulator 1824 or the repeater entirely can be placed in a WLAN
only configuration by, for example, the processor 1825.
[0058] The output of the comparator 1823 is fed to a sequencer 1826 (CMP_A_EN
terminal). The comparator 1823 can output a signal indicative of a detected signal when the RSSI is greater than the predetermined threshold, thus indicative of a signal to be repeated. In response to the signal from the comparator 1823, as well as other indications, the sequencer 1826 will output an enable signal (not shown) to the demodulator 1824 to begin demodulating the signal as well as various control outputs that will begin the physical repeating of the signal. Subsequently, the sequencer 1826 will also output a signal to an AND gate 1828. The AND gate 1828 also receives a = microprocessor enable signal from the processor 1825, and outputs an enable signal to timing circuitry 1830 if the enable signals are received from both the sequencer 1826 and the processor 1825. The timing circuitry 1830 controls a bi-phase modulator (signal modification device) 1832, which receives the output signal from the AGC
element 1822 via an amplifier 1834 and additional circuitry. An exemplary circuit for the timing circuitry 1830 is shown in FIG. 19. PA_EN represents the enable signal from the sequencer 1826, and BPSK_EN represents the enable signal from the processor 1825. 11 MHz is the clock for the timing circuitry 1830.
terminal). The comparator 1823 can output a signal indicative of a detected signal when the RSSI is greater than the predetermined threshold, thus indicative of a signal to be repeated. In response to the signal from the comparator 1823, as well as other indications, the sequencer 1826 will output an enable signal (not shown) to the demodulator 1824 to begin demodulating the signal as well as various control outputs that will begin the physical repeating of the signal. Subsequently, the sequencer 1826 will also output a signal to an AND gate 1828. The AND gate 1828 also receives a = microprocessor enable signal from the processor 1825, and outputs an enable signal to timing circuitry 1830 if the enable signals are received from both the sequencer 1826 and the processor 1825. The timing circuitry 1830 controls a bi-phase modulator (signal modification device) 1832, which receives the output signal from the AGC
element 1822 via an amplifier 1834 and additional circuitry. An exemplary circuit for the timing circuitry 1830 is shown in FIG. 19. PA_EN represents the enable signal from the sequencer 1826, and BPSK_EN represents the enable signal from the processor 1825. 11 MHz is the clock for the timing circuitry 1830.
[0059] The bi-phase modulator 1832 modifies the signal by adding an amount of phase variation to modulate, for example, the first few symbols of a packet to be repeated. The bi-phase modulator 1832 can include, for example, transfer switches for switching the differential signal received from the amplifier 1834 to thereby add the phase variation. An exemplary circuit for the bi-phase modulator 1832 is shown in FIG.
20. The length of time for applying the phase modulation to the repeated signal can be adjusted by the timing circuitry 1830 connected to the comparator output (see signals MOD_P and MOD _N which are from the timing circuitry 1830). The timing circuitry 1830 can be triggered by a hit on the comparator 1823. Once the timing circuitry 1830 stops, the switching of the positive and negative inputs can be stopped and normal operation can be commenced.
20. The length of time for applying the phase modulation to the repeated signal can be adjusted by the timing circuitry 1830 connected to the comparator output (see signals MOD_P and MOD _N which are from the timing circuitry 1830). The timing circuitry 1830 can be triggered by a hit on the comparator 1823. Once the timing circuitry 1830 stops, the switching of the positive and negative inputs can be stopped and normal operation can be commenced.
[0060] The output of the bi-phase modulator 1832 is fed to a SAW filter 1836 for removing any spectral splattering created by the phase modulation performed by the bi-phase modulator 1832. The signal can then be transmitted by one of the first or second antennas ANTA, ANTB via the mixer 1838 and additional analog elements to an access point, wireless station or client device (wireless station).
[0061] Referring to FIG. 18B, in a modification to the first embodiment, the bi-phase modulator 1832 can be coupled to, for example, a 1056 MHz linear oscillator 1840 and an active mixer 1842. The length of time for applying the phase modulation to the repeated signal is still adjusted by the timing circuitry 1830. The positive and negative inputs of the 1056 MHz linear oscillator 1840 going to the active mixer 1842 can be switched back and forth at, for example, a 5.5 MHz rate. Switching the positive and negative inputs will impart the phase modulation onto the repeated signal.
Once the timing circuitry 1830 stops, the switching of the positive and negative inputs can be stopped and normal operation can be commenced.
Once the timing circuitry 1830 stops, the switching of the positive and negative inputs can be stopped and normal operation can be commenced.
[0062] During repeater operation, when the repeater 1800 is placed in the standard operating mode of WLAN only, the digital demodulator 1824 (DSSS/OFDM detector) will not recognize packets having symbols phase modulated by another repeater as valid WLAN packets, thereby stopping the repeating process because the existing phase relationships are disrupted by the signal modification. Therefore, when the repeater 1800 receives a repeated signal from a similar repeater 1800, it will not re-repeat the signal.
As a result, the problem related to oscillation as discussed above can be mitigated.
As a result, the problem related to oscillation as discussed above can be mitigated.
[0063] Further, the phase variation added to the signal by the bi-phase modulator 1832 is transparent to wireless stations receiving the modified signal because carrier recovery is not performed until, for example, the fifth or sixth symbol of an incoming stream.
[0064] In an alternative embodiment, an external phase modulator can advantageously be placed after the amplifier 1834. In addition, a simple timer to control the 5.5MHz clock can be generated by dividing down an existing clock such as an 11 MHz processor clock. Further, the signal modification can be performed at the output of the mixer 1838 rather than the amplifier. However, the output of amplifier 1834 is preferably used because of the difficulty accessing the data stream coming out of the modulator in order to add the phase at base-band for signals coming out of the modulator.
Accordingly, the phase modulator 1832 is triggered by either a comparator hit or anytime a modulated signal is generated. It should be noted that the signal modified may be a self-generated signal or a received signal.
Accordingly, the phase modulator 1832 is triggered by either a comparator hit or anytime a modulated signal is generated. It should be noted that the signal modified may be a self-generated signal or a received signal.
[0065] Returning to the exemplary scenario 300 illustrated in FIG. 17, advantages achieved by the repeater implemented according to the various embodiments above will be discussed. Here, assuming that the repeaters R1 320 and R2 330 both include the digital demodulator 1824 and phase modulator 1832, and are both placed in a WLAN
only configuration, if the repeaters R1 320 and R2 330 are operating on the same pair of channels, such as AP and repeater channels, when AP 310 transmits, both R1 320 and R2 330 detect the transmission on, for example, the first frequency Fl and retransmit on the second frequency F2. However, before transmission, the phase modulator 1832 of the repeater modifies the first few symbols of packets in the transmitted signal.
When an isolated client station STA 340 transmits on F2, R2 330 then repeats the transmission on Fl to AP 310. R1 320 detects the transmissions from R2 330 on Fl; however, RI
cannot demodulate the repeated signal because the first few symbols include the phase variation. Thus, the repeater R2 330 does not retransmit the detected transmissions back onto F2 302. Even if R1 320 happens to select F2 as the transmit frequency, a loop will not be established between R1 320 and R2 330.
only configuration, if the repeaters R1 320 and R2 330 are operating on the same pair of channels, such as AP and repeater channels, when AP 310 transmits, both R1 320 and R2 330 detect the transmission on, for example, the first frequency Fl and retransmit on the second frequency F2. However, before transmission, the phase modulator 1832 of the repeater modifies the first few symbols of packets in the transmitted signal.
When an isolated client station STA 340 transmits on F2, R2 330 then repeats the transmission on Fl to AP 310. R1 320 detects the transmissions from R2 330 on Fl; however, RI
cannot demodulate the repeated signal because the first few symbols include the phase variation. Thus, the repeater R2 330 does not retransmit the detected transmissions back onto F2 302. Even if R1 320 happens to select F2 as the transmit frequency, a loop will not be established between R1 320 and R2 330.
[0066] A further advantage of the repeater according to the various embodiments is that limited or no additional analog, digital or I/O circuitry is needed for phase detection because such phase detection is performed by the existing circuitry for the OFDM/DSSS
digital modulator. The circuitry for generating the phase modulation is extremely simple.
digital modulator. The circuitry for generating the phase modulation is extremely simple.
[0067] Accordingly, if an amount of phase variation is deliberately modulated onto the first few symbols of a repeated packet and the standard operating mode of "WLAN
only" is enabled, the existing DSSS and OFDM detector will not recognize the packets associated with the phase modulated symbols as valid WLAN packets and will stop the repeating process.
only" is enabled, the existing DSSS and OFDM detector will not recognize the packets associated with the phase modulated symbols as valid WLAN packets and will stop the repeating process.
[0068] The biphase modulator 1832 can be modified to perform the phase modulation of the preamble so that each packet has a unique signature. This signature may be a unique phase modulating "square wave" with a unique frequency of a set of frequencies or one of a set of orthogonal codes such as Walsh codes or the like. While it is not required that the code be orthogonal, orthogonal orientation between the codes is considered to allow for a highet performance of the detection of the one out of the set of codes with more certainty. Examples of non-orthogonal code would be ones with low cross correlations such as PN codes, Gold codes, or Barker sequences. Use of such codes as the modulation sequence by the repeater onto the preamble of the repeated packet will allow for (as previously mentioned) preventing the "wireless LAN
only"
detection of the signal to be prevented in a similar manner to the tests discussed below.
only"
detection of the signal to be prevented in a similar manner to the tests discussed below.
[0069] Further, the unique signature can be configured so that operation of a repeater receiving the modified signal is adjusted in accordance with the unique signature. For example, rather than the repeater not repeating the signal when it includes the phase modulated preamble, the repeater can be configured to take alternative actions such as transmitting the wireless signal at a frequency different from an original transmission frequency, or transmitting the wireless signal at a power level different from the original transmission power level in order to avoid oscillation. Also, the repeater could be configured to remove the unique signature from the signal. The repeater can be configured to perform such actions in accordance with the processor 1825 executing instructions stored in an associated memory.
[0070] Further, the repeater can use the phase modulation in the signal to perform a qualifying detection process to determine if the received wireless signal is from another repeater or one of the wireless stations. Particularly, the phase modulation can be correlated to predetermined signal pattern stored in the memory. If the correlation is determined to be high, then the repeater can determine that the wireless signal is from another repeater and take appropriate action to prevent oscillation.
Alternatively, the qualifying detection process can include demodulating one of a predetermined information sequence, a pilot channel and a pilot carrier.
Alternatively, the qualifying detection process can include demodulating one of a predetermined information sequence, a pilot channel and a pilot carrier.
[0071] Various tests were performed on an exemplary repeater which validated the conclusions discussed above. In the tests, the search time for WLAN detection in an exemplary repeater was programmable from 4pts to 16 s. A digital signal was generated using a Vector Signal Generator (VSG) having phase modulation on the first 41.1s for both an OFDM signal and a DSSS signal. As discussed below, cessation of repeating was achieved 100% of the time for a programmed search time of 40.
[0072] Next, the operating mode of the exemplary repeater was changed to "WLAN
only" OFF. The signal successfully transited the repeater 100% of the time and a Vector Signal Analyzer (VSA) successfully demodulated the repeated signal including the phase modulation. As a control, the signal was input with the phase modulation imposed directly from the VSG and, when output to the VSA, the signal with the direct modulation was again successfully demodulated.
=
only" OFF. The signal successfully transited the repeater 100% of the time and a Vector Signal Analyzer (VSA) successfully demodulated the repeated signal including the phase modulation. As a control, the signal was input with the phase modulation imposed directly from the VSG and, when output to the VSA, the signal with the direct modulation was again successfully demodulated.
=
[0073] TIME DOMAIN OPERATION: Referring to FIGS. lA - 4B, test conditions and associated results for DSSS signals will be discussed.
[0074] In "Test #1_DSSS," a 1Mbps DSSS signal was injected without any phase modulation into the exemplary repeater while WLAN Only was enabled and the output was measured. As shown in FIGs. 1A - 1B, the exemplary repeater fully repeated the signal and the VSA demodulator detected the Start Frame Delimiter (SFD) and Header.
[0075] In "Test #2_DSSS," a 1Mbps DSSS signal with Bi-Phase Modulation added to the first 411s of the signal was injected into the exemplary repeater while WLAN Only was enabled and the output was measured. The repeater in WLAN Only mode is set to search 411s for an 802.11g DSSS or OFDM packet. As shown in FIGs. 2A - 2B, the exemplary repeater repeated only 4 ,s (partial packet) and then stopped the transmission.
[0076] In "Test #3 DSSS," a 1Mbps DSSS signal with Bi-Phase Modulation added to the first 4pts of the signal was injected into the exemplary repeater while WLAN Only disabled and the output was measured. As shown in FIGs. 3A - 3B, since the WLAN
Only mode is disabled, the exemplary repeater repeated the entire packet since it was not searching for DSSS or OFDM preambles, and the VSA detected and demodulated the packet.
Only mode is disabled, the exemplary repeater repeated the entire packet since it was not searching for DSSS or OFDM preambles, and the VSA detected and demodulated the packet.
[0077] In "Test #3_DSSS Zoom" a zoomed version of Test #3_DSSS was performed in which the phase was added across the first 4 s. As shown in FIG. 4B, the time domain signal appeared differently for the first 4us compared to after 4 s.
[0078] Referring to FIGs. 5A - 7B, test conditions and associated results for OFDM
signals will be discussed.
signals will be discussed.
[0079] In "Test #1 OFDM," a 6Mbps OFDM signal without any phase modulation was injected into the exemplary repeater with WLAN Only enabled and the output was measured. As shown in FIGs. 5A - 5B, the exemplary repeater fully repeated the signal and the VSA demodulator detected and properly demodulated the signal.
[0080] In "Test #2_0FDM," a 6Mbps OFDM signal with Bi-Phase Modulation added to the first 4us of the signal was injected into the exemplary repeater with WLAN
Only enabled and the output was measured. Exemplary repeater WLAN Only was set to search 4iis for an 802.11g DSSS or OFDM. As shown in FIGs. 6A - 6B, the exemplary repeater repeated only 41.ts (partial packet) and then stopped the transmission.
Only enabled and the output was measured. Exemplary repeater WLAN Only was set to search 4iis for an 802.11g DSSS or OFDM. As shown in FIGs. 6A - 6B, the exemplary repeater repeated only 41.ts (partial packet) and then stopped the transmission.
[0081] In "Test #3_0FDM," a 6Mbps OFDM signal with Bi-Phase Modulation added to the first 4iis of the signal was injected into the exemplary repeater with WLAN
Only disabled and the output was measured. As shown in FIGs. 7A - 7B, since WLAN
Only is disabled the exemplary repeater repeated the entire packet since it was not searching for DSSS or OFDM preambles, and the VSA detected and demodulated the packet.
Only disabled and the output was measured. As shown in FIGs. 7A - 7B, since WLAN
Only is disabled the exemplary repeater repeated the entire packet since it was not searching for DSSS or OFDM preambles, and the VSA detected and demodulated the packet.
[0082] Frequency Domain Operation: Referring to FIGS. 8A - 15B, spectral implications of adding the phase modulation to the signal for OFDM and DSSS
and the appearance of the spectrum after being transmitted through the IF SAWs will be discussed. The test was performed at 594MHz in order to determine if the signal could pass or be very close to the mask defined by the 802.11 standard.
and the appearance of the spectrum after being transmitted through the IF SAWs will be discussed. The test was performed at 594MHz in order to determine if the signal could pass or be very close to the mask defined by the 802.11 standard.
[0083] Referring to FIGs. 8A - 11B, test conditions and associated results for OFDM
signals will be discussed.
signals will be discussed.
[0084] In "Test #1 OFDM" a 6Mbps OFDM signal was injected into the spectrum analyzer without any phase modulation. As shown in FIG. 8B, the signal generated passed the 802.11g spectral masks.
[0085] In "Test #2 OFDM" a 6Mbps OFDM signal was injected into the spectrum analyzer with phase modulation added to the first 4 s of the waveform. As shown in FIG. 9B, the signal generated did not pass the 802.11g spectral masks due to the phase modulation.
[0086] In "Test #3 OFDM" a 6Mbps OFDM signal was injected into the 594MHz SAW filter and then into the spectrum analyzer with phase modulation added to the first 4pts of the waveform. As shown in FIG. 10B, although the signal was very close due to the phase modulation, it passed the 802.11g spectral masks. It should be noted that when the bi-phase modulator is implemented externally, the signal will only go through the low loss SAW filter because the bi-phase modulator would have to be added after the amplifier so that the phase modulation could also be added to the internal modulator.
[0087] In "Test #4 OFDM" a 6Mbps OFDM signal was injected into 594MHz low loss and high rejection SAWs and then into the spectrum analyzer with phase modulation added to the first 4pts of the waveform. As shown in FIG. 11B, although the signal was very close due to the phase modulation, the signal passed the 802.11g spectral masks. It should be noted that when the bi-phase modulator is implemented internally to the repeater, the signal would go through both the low loss and high rejection SAWs because the bi-phase modulation would be added to the active inter-stage mixer.
[0088] Referring to FIGs. 12A - 15B, test conditions and associated results for DSSS
signals will be discussed. In "Test #1_DSSS," a 1Mbps DSSS signal was injected into the spectrum analyzer without any phase modulation. As shown in FIG. 12B, the signal generated passed the 802.11b spectral masks.
signals will be discussed. In "Test #1_DSSS," a 1Mbps DSSS signal was injected into the spectrum analyzer without any phase modulation. As shown in FIG. 12B, the signal generated passed the 802.11b spectral masks.
[0089] In "Test #2 DSSS," a 1Mbps DSSS signal was injected into the spectrum analyzer with phase modulation added to the first 411s of the waveform. As shown in FIG. 13B, the signal no longer passed or was close to failing the 802.11b spectral masks due to the phase modulation.
[0090] In "Test #3 DSSS," a 1Mbps DSSS signal was injected into the 594MHz low loss SAW and then into the spectrum analyzer with phase modulation added to the first 4us of the waveform. As shown in FIG. 14B, although the signal was very close due to the phase modulation, the signal passed the 802.11b spectral masks.
[0091] In "Test #4 DSSS," a 1Mbps DSSS signal was injected into the 594MHz low loss and high rejection SAWs and then into the spectrum analyzer with phase modulation added to the first 41.ts of the waveform. As shown in FIG. 15B, although the signal was very close due to the phase modulation, it passed the 802.11b spectral masks.
It should be noted that when the phase modulation is performed internally the signal would go through both the low loss and high rejection SAWs because the bi-phase modulation would be added to the active inter-stage mixer.
It should be noted that when the phase modulation is performed internally the signal would go through both the low loss and high rejection SAWs because the bi-phase modulation would be added to the active inter-stage mixer.
[0092] Therefore, a repeater including the bi-phase modulation device 1832 can fully repeat a signal and not repeat a signal if a predetermined portion of the signal includes phase modulation and is in a WLAN only mode. Further, the modulated signal generated can pass through the 802.11 spectral masks when the modulated signal passes through one or more SAW filters. Here, the bi-phase modulator 1832 constitutes a signal modification device.
=
=
[0093] Referring to FIG. 21, a repeater according to a second embodiment can include a notch processor 2100 configured to insert a notch pattern on a wireless signal to be repeated and detect if a notch pattern is present on a received wireless signal. The notch processor 2100 can be included in the repeater 1800 shown in FIGs. 18A -18B as an additional signal modification device and detection device or in place of the bi-phase modulator 1832. As shown in FIG. 22, the notch pattern is generally one or more notches starting at a specific time TsTART and separated by a gap duration TpuRATioN.
The start time, gap duration, and notch duration are programmable for both insertion and detection.
The detection notch pattern is specified by setting the coefficients of the received notch matched filter. Further, the notch patterns can be different for transmission and reception.
The start time, gap duration, and notch duration are programmable for both insertion and detection.
The detection notch pattern is specified by setting the coefficients of the received notch matched filter. Further, the notch patterns can be different for transmission and reception.
[0094] Returning to FIG. 21, the notch processor 2100 includes a notch insertion portion 2102 for sending a signal representative of the notch pattern (TX
NOTCH) to the sequencer 2104, a notch detection portion 2106 for sending signals representative of an indication of a detected notch (R)( NOTCH DET) and the particular channel on which the notch was detected (RX NOTCH CHAN) to the sequencer 2104, a comparator portion 2108 that receives input signals (CMP_OUT_A, CMP_OUT_B) from the comparators via an internal RF interface 2110, and clock and reset signals, and control registers 2112 for sending signal representative of a notch insertion start time TX NOTCH START, notch insertion gap control TX NOTCH GAP, and duration TX NOTCH DUR to the notch insertion portion 2102. The comparator portion 2108 receives signals representative of the RSSI voltages for the two channels and a clock signal from an RSSI analog to digital converter (ADC) interface 2113, and outputs signals (RX_HYST_A, RX_HYST_B, and RX_ADC_SEL) to an optional debugging header portion 2114 for facilitating parameter adjustment.
NOTCH) to the sequencer 2104, a notch detection portion 2106 for sending signals representative of an indication of a detected notch (R)( NOTCH DET) and the particular channel on which the notch was detected (RX NOTCH CHAN) to the sequencer 2104, a comparator portion 2108 that receives input signals (CMP_OUT_A, CMP_OUT_B) from the comparators via an internal RF interface 2110, and clock and reset signals, and control registers 2112 for sending signal representative of a notch insertion start time TX NOTCH START, notch insertion gap control TX NOTCH GAP, and duration TX NOTCH DUR to the notch insertion portion 2102. The comparator portion 2108 receives signals representative of the RSSI voltages for the two channels and a clock signal from an RSSI analog to digital converter (ADC) interface 2113, and outputs signals (RX_HYST_A, RX_HYST_B, and RX_ADC_SEL) to an optional debugging header portion 2114 for facilitating parameter adjustment.
[0095] The notch processor 2100 further includes control and status registers for outputting various signals representative of: matched filter peak windows (RX_NOTCH_MFPW1, RX_NOTCH_MFPW2); notch detection hysteresis control (RX_NOTCH_HYST); notch detection parameter control (RX_NOTCH_PAR1, RX NOTCH PAR2, RX NOTCH PAR3); and notch detection matched filter coefficient control (RX_NOTCH_MFC0 - MFC19) to the notch detection section 2106.
The notch detection section 2106 also outputs a signal representative of notch detection status (R)(_NOTCH_STATUS) to the control and status registers 2116.
The notch detection section 2106 also outputs a signal representative of notch detection status (R)(_NOTCH_STATUS) to the control and status registers 2116.
[0096] Returning to FIG. 22, during operation, the notch processor 2100 can insert one or two short notches in the signal to be repeated after the rising edge of CMP_OUT_A or CMP_OUT_B. The sequencer 2104 applies the notch to the repeated signal whenever TX NOTCH is 1. Exemplary notch processor operations for detecting a notch in a signal will be discussed with reference to the flow diagram shown in FIG. 23.
[0097] At 2305, programmable hysteresis is performed to generate the hysteresis-filtered comparator outputs HYST_A, HYST_B, and the ADC channel selection signal ADC_SEL based upon the analog comparator outputs CMP_OUT_A, CMP_OUT_B.
The signal RXND_HYST_CR is a signal from a control register indicative of the hysteresis span for CMP_OUT_A, CMP_OUT_B.
The signal RXND_HYST_CR is a signal from a control register indicative of the hysteresis span for CMP_OUT_A, CMP_OUT_B.
[0098] At 2310, RSSI channel selection is performed based upon signals HYST_A, HYST_B, and a signal ADC_SEL representative of the selective channel is generated.
At 2315, HYST_A, HYST_B, and ADC_SEL are used to control the signals from the timer MFPW TMR for controlling the detection window timing. The timer control is performed based upon the number of clock cycles elapsed since the packet's start.
MFPW TMR continues counting during temporary signal dropouts shorter than RXND DROPOUT CR clock cycles. Such dropouts frequently occur during the notch pattern at low received signal strengths.
At 2315, HYST_A, HYST_B, and ADC_SEL are used to control the signals from the timer MFPW TMR for controlling the detection window timing. The timer control is performed based upon the number of clock cycles elapsed since the packet's start.
MFPW TMR continues counting during temporary signal dropouts shorter than RXND DROPOUT CR clock cycles. Such dropouts frequently occur during the notch pattern at low received signal strengths.
[0099] At 2320, ADC_SEL is used to convert the two-channel interleaved RSSI
output ADC_OUT into a single-channel de-multiplexed signal ADC_DATA. At 2325, ADC_DATA is processed through a non-linear "maximum of 3" operation to generate ADC MAX. RXND MAX DISABLE CR is for disabling the use of the 3-sample maximum.
output ADC_OUT into a single-channel de-multiplexed signal ADC_DATA. At 2325, ADC_DATA is processed through a non-linear "maximum of 3" operation to generate ADC MAX. RXND MAX DISABLE CR is for disabling the use of the 3-sample maximum.
[00100] At 2330, ADC_MAX is processed through a linear first-order programmable lowpass filter, which yields a slowly-varying value RSSI_AVG that closely tracks the received signal envelope peak excursions. At 2335, a slightly delayed copy of ADC_DATA, referred to as RSSI_VAL is subtracted from RSSI_AVG to yield the (signed) difference signal DIFF, which exhibits a strong positive excursion when a notch is encountered.
[00101] At 2340, DIFF is the input to a 20-tap programmable matched filter, whose unsigned output MF_SUM is clipped to the range 0 to 255. Signal RXND_MFC[0-19]_ENA is representative of a match filter tap status, RXND_MFC[0-19]_SIGN is representative of a matched filter tap coefficient sign, and signal RXND_MFC[0-19]_SHIFT is representative of a matched filter tap coefficient magnitude.
[00102] At 2345, RSSI_AVG is used to compute a variable matched filter threshold MF THRESH based on the values of parameter control registers RXND MFT CONST CR, RXND MFT SLOPE CR, and RXND MFT MAX CR.
[00103] At 2350, the notch detection section sets RX NOTCH DET to 1 and sets RX NOTCH CHAN equal to ADC SEL, whenever MF SUM equals or exceeds MF THRESH during a narrow time window specified by control registers RXND NOM MFPW CR and RXND HWIN MFPW CR. The signals RX NOTCH DET and RX NOTCH CHAN are sent to the sequencer 2104.
[00104] Thus, a repeater including the notch processor 2100 according to the second embodiment can add a notch pattern to a repeated signal and detect a notch pattern in a received signal to mitigate the oscillation problem discussed above. Here, the notch processor 2100 constitutes a signal modification device.
[00105] According to a third embodiment, a repeater such as the repeater 1800 shown in FIGs. 18A - 18B executes a power adjustment routine to stop or prevent oscillation with one or more other repeaters. The routine can begin when the repeater 1800 enters a discovery mode upon determining that another repeater within the wireless network is operating in the same frequency channel as disclosed in, for example, U.S.
Patent Publication No. 2006-0041680. The repeater 1800 can be configured to execute the routine by the processor 1825 executing instructions stored in the memory 1827.
Patent Publication No. 2006-0041680. The repeater 1800 can be configured to execute the routine by the processor 1825 executing instructions stored in the memory 1827.
[00106] Referring to the flow diagram of FIG. 24, the power adjustment routine will be discussed more fully. At 2405, the repeater transmits a predetermined number of XOS PROBE REQUEST packets, and at 2410 measures the XOS PROBE RESPONSE RSSI. The packets can be generated by, for example, the = 28 digital demodulator 1824 under the control of the processor 1825. The XOS PROBE REQUEST packet contains the power at which the repeater is transmitting. The difference between the transmit power and measured RSSI is the one-way path loss. At 2415, the repeater determines if this path loss is less than a predetermined value such as, for example, 80dB. If the path loss is less than 80 dB (YES
at 2415), then at 2420 the repeater will mark this channel and all channels within a 5 channel separation as unavailable for use, and the routine ends.
at 2415), then at 2420 the repeater will mark this channel and all channels within a 5 channel separation as unavailable for use, and the routine ends.
[00107] If the path loss is less than 80 dB (NO at 2415), then at 2425 the repeater transmits a number of XOS packets of a maximum length (64 bytes). At 2430, the RSSI
from each successfully received packet is measured and averaged across all packets. A
packet which has not been successfully received will be considered to have an RSSI of -80dBm. At 2435, the repeater determines if the average RSSI is less than a predetermined dBm. If the average RSSI is less than the predetermined dBm (YES
at 2435), then the routine ends. That is, the discovering repeater will assume that the current transmit power is acceptable and begin normal operation.
from each successfully received packet is measured and averaged across all packets. A
packet which has not been successfully received will be considered to have an RSSI of -80dBm. At 2435, the repeater determines if the average RSSI is less than a predetermined dBm. If the average RSSI is less than the predetermined dBm (YES
at 2435), then the routine ends. That is, the discovering repeater will assume that the current transmit power is acceptable and begin normal operation.
[00108] If the average RSSI is not less than the predetermined dBm (NO at 2435), then at 2440 the repeater adjusts the transmission power down by 1 dB and at retransmits the number of XOS packets. At 2450, the repeater determines if the average RSSI is less than the predetermined dBm. If the average RSSI is less than the predetermined dBm (YES at 2450), then the repeater begins normal operation.
[00109] If the average RSSI is not less than the predetermined dBm (NO at 2450), then at 2455 the repeater requests that the other repeater(s) on the same channel reduce the transmit power by 1 dB. At 2460 the repeater transmits the number of XOS
packets.
At 2465, the RSSI from each successfully received packet is measured and averaged across all packets. At 2470, the repeater determines if the average RSSI is less than the predetermined dBm. If the average RSSI is less than the predetermined dBm (YES
at 2470), then the repeater begins normal operation.
packets.
At 2465, the RSSI from each successfully received packet is measured and averaged across all packets. At 2470, the repeater determines if the average RSSI is less than the predetermined dBm. If the average RSSI is less than the predetermined dBm (YES
at 2470), then the repeater begins normal operation.
[00110] If the average RSSI is still not less than the predetermined dBm (NO
at 2470), then the repeater once again request that the other repeater(s) on its same channel reduce the transmit power by another 1 dB. This will continue with each repeater's power being dropped by 1 dBm, in turn, until the XOS packet test passes. However, if the non-discovering repeater would have to reduce it's transmit power to less than a predetermined amount such as, for example, 9 dB, the discovering repeater will request that the other repeater return to its original transmit power and the discovering repeater can choose a different channel to repeat onto. The current channel and all channels within a 5 channel separation will be marked as unavailable.
at 2470), then the repeater once again request that the other repeater(s) on its same channel reduce the transmit power by another 1 dB. This will continue with each repeater's power being dropped by 1 dBm, in turn, until the XOS packet test passes. However, if the non-discovering repeater would have to reduce it's transmit power to less than a predetermined amount such as, for example, 9 dB, the discovering repeater will request that the other repeater return to its original transmit power and the discovering repeater can choose a different channel to repeat onto. The current channel and all channels within a 5 channel separation will be marked as unavailable.
[00111] While the repeater is operating on the same channels as another repeater, the repeater which was enabled last will enable a monitor that checks for oscillations to occur. When an oscillation is detected, the repeater will perform the same power routine discussed above (2405 - 2420).
[00112] In addition, for every predetermined time period (e.g., 20 seconds) the monitoring repeater will attempt to increase it's transmit power by ldB until it has reached it's normal maximum transmit power. Each time the power on either repeater is incremented, an XOS test (2405 - 2420) will be performed to see if the increase is warranted. It will ratchet each side up in the same manner as the powers were dropped.
Once a repeater has been requested to change the transmit power by another repeater, it can monitor the channel for a XOS _ OSCMIT_ HEARTBEAT messages from the controlling repeater. If a predetermined time period such as, for example, 20 seconds passes without receiving a heartbeat message from the controlling repeater, the slave unit will assume that the controlling repeater is no longer operating and will revert the power to the normal maximum transmit power for channel spacing configuration.
Once a repeater has been requested to change the transmit power by another repeater, it can monitor the channel for a XOS _ OSCMIT_ HEARTBEAT messages from the controlling repeater. If a predetermined time period such as, for example, 20 seconds passes without receiving a heartbeat message from the controlling repeater, the slave unit will assume that the controlling repeater is no longer operating and will revert the power to the normal maximum transmit power for channel spacing configuration.
[00113] The above routine can also be applied when more than one other repeater is repeating to the same channels. However, in such as case a monitoring repeater may choose not to increase the power if it has determined within the certain time period (e.g., seconds) that an oscillation would occur by doing so.
[00114] Thus, the repeater 1800 according to the third embodiment can execute the power adjustment routine to mitigate oscillation with one or more other receivers on a same channel within a wireless network.
[00115] This disclosure is intended to explain how to fashion and use various embodiments in accordance with the invention rather than to limit the true, intended, and fair scope and spirit thereof. The foregoing description is not intended to be exhaustive or to limit the invention to the precise form disclosed. Modifications or variations are possible in light of the above teachings. For example, the repeater may be modified to identify packets previously repeated, and perform an action in response. The action may be to terminate transmission for oscillation mitigation, or to allow repeating depending on the specifics of the detection.
[00116] Further, a repeater can incorporate any number of the three embodiments discussed above. That is, the repeater is not limited to only one of the above-discussed embodiments. Further, the circuits discussed above are only exemplary manner for implementing the above described signal modification device. That is, the bi-phase modulation device 1832 and the notch processor 2100 can be implemented in a different manner, as long as a predetermined portion of the signal is modified so that a repeater receiving the modified signal takes an action different from its normal repeating action.
[00117] The embodiment(s) was chosen and described to provide the best illustration of the principles of the invention and its practical application, and to enable one of ordinary skill in the art to utilize the invention in various embodiments and with various modifications as are suited to the particular use contemplated. All such modifications and variations are within the scope of the invention. The various circuits described above can be implemented in discrete circuits or integrated circuits, as desired by implementation. Further, portions of the invention may be implemented in software or the like as will be appreciated by one of skill in the art and can be embodied as methods associated with the content described herein.
Claims (20)
1. A first repeater operating within a wireless network, the wireless network including a second repeater capable of communicating with the first repeater, and first and second wireless station devices capable of communicating with at least one of the first repeater and the second repeater, the first repeater comprising:
a reception device for receiving a wireless signal at a reception frequency;
a detector for detecting if a predetermined portion of the received wireless signal includes a modified portion to thereby determine that the received signal is from the second repeater; and a transmission device for transmitting the wireless signal to one of the first and second wireless station devices at a transmission frequency to thereby repeat the wireless signal, wherein the repeater further comprises:
a processor; and a memory coupled to the processor, the memory for storing a power adjustment routine for configuring the processor;
wherein the processor is configured to:
generate probe packets to be transmitted to the second repeater at the transmission frequency;
measure a received signal strength indication (RSSI) of a packet received in response to the probe packets;
determine if a path loss defined by a difference between a power level at which the probe packets were transmitted and the measured RSSI is less than a predetermined value;
and mark the transmission frequency as unavailable for use if the path loss is less than the predetermined value.
a reception device for receiving a wireless signal at a reception frequency;
a detector for detecting if a predetermined portion of the received wireless signal includes a modified portion to thereby determine that the received signal is from the second repeater; and a transmission device for transmitting the wireless signal to one of the first and second wireless station devices at a transmission frequency to thereby repeat the wireless signal, wherein the repeater further comprises:
a processor; and a memory coupled to the processor, the memory for storing a power adjustment routine for configuring the processor;
wherein the processor is configured to:
generate probe packets to be transmitted to the second repeater at the transmission frequency;
measure a received signal strength indication (RSSI) of a packet received in response to the probe packets;
determine if a path loss defined by a difference between a power level at which the probe packets were transmitted and the measured RSSI is less than a predetermined value;
and mark the transmission frequency as unavailable for use if the path loss is less than the predetermined value.
2. The first repeater of claim 1, wherein the processor is further configured to:
generate a group of packets to be transmitted to the second repeater at the transmission frequency if the path loss is not less than approximately the predetermined value;
determine an average RSSI for the group of packets;
if the average RSSI is less than a predetermined level, mark a current transmission power as acceptable.
generate a group of packets to be transmitted to the second repeater at the transmission frequency if the path loss is not less than approximately the predetermined value;
determine an average RSSI for the group of packets;
if the average RSSI is less than a predetermined level, mark a current transmission power as acceptable.
3. The first repeater of claim 2, wherein the processor is further configured to:
adjust the current transmission power downward by a predetermined decibel level if the average RSSI is not less than the predetermined level;
regenerate the group of packets to be transmitted to the second repeater at the transmission frequency;
determine an average RSSI for the group of packets; and if the average RSSI is less than a predetermined level, mark a current transmission power as acceptable.
adjust the current transmission power downward by a predetermined decibel level if the average RSSI is not less than the predetermined level;
regenerate the group of packets to be transmitted to the second repeater at the transmission frequency;
determine an average RSSI for the group of packets; and if the average RSSI is less than a predetermined level, mark a current transmission power as acceptable.
4. A first repeater operating within a wireless network, the wireless network including a second repeater capable of communicating with the first repeater, and first and second wireless stations capable of communicating with at least one of the first repeater and the second repeater, the first repeater comprising:
a reception device receiving a wireless signal from one of the second repeater, first wireless station, and second wireless station;
a detection device coupled to the reception device, the detection device detecting if a received signal strength indication (RSSI) of the wireless signal is greater than a predetermined RSSI threshold;
a digital demodulator coupled to the reception device, the digital demodulator configured to demodulate the wireless signal if the detected RSSI is greater than the predetermined RSSI threshold;
a signal modification device coupled to the reception device, the signal modification device configured to modify a predetermined portion of the wireless signal; and a transmission device coupled to the signal modification device for transmitting the modified wireless signal to one of the second repeater, first wireless station, and second wireless station;
wherein the signal modification device includes a bi-phase modulation device configured to modulate a phase of the predetermined portion of the wireless signal, and wherein the bi-phase modulator includes a transfer switch coupled to a linear oscillator (LO), the transfer switch switching positive and negative terminals of the LO at a predetermined frequency to modulate the phase of the predetermined portion of the wireless signal.
a reception device receiving a wireless signal from one of the second repeater, first wireless station, and second wireless station;
a detection device coupled to the reception device, the detection device detecting if a received signal strength indication (RSSI) of the wireless signal is greater than a predetermined RSSI threshold;
a digital demodulator coupled to the reception device, the digital demodulator configured to demodulate the wireless signal if the detected RSSI is greater than the predetermined RSSI threshold;
a signal modification device coupled to the reception device, the signal modification device configured to modify a predetermined portion of the wireless signal; and a transmission device coupled to the signal modification device for transmitting the modified wireless signal to one of the second repeater, first wireless station, and second wireless station;
wherein the signal modification device includes a bi-phase modulation device configured to modulate a phase of the predetermined portion of the wireless signal, and wherein the bi-phase modulator includes a transfer switch coupled to a linear oscillator (LO), the transfer switch switching positive and negative terminals of the LO at a predetermined frequency to modulate the phase of the predetermined portion of the wireless signal.
5. A first repeater operating within a wireless network, the wireless network including a second repeater capable of communicating with the first repeater, and first and second wireless stations capable of communicating with at least one of the first repeater and the second repeater, the first repeater comprising:
a reception device receiving a wireless signal including one or more packets at a reception frequency;
a signal modification and detection device coupled to the reception device, the signal modification and detection device configured to modify a predetermined portion of the packet to thereby generate a modified wireless signal and to detect if a predetermined portion of the packet includes a modified signal pattern;
a transmission device coupled to the signal modification and detection device for transmitting the modified wireless signal to one of the second repeater, first wireless station, and second wireless station at a predetermined power level and a transmission frequency;
a processor controlling the reception device and the transmission device; and a memory coupled to the processor, the memory for storing a power adjustment routine for configuring the processor to:
generate probe packets to be transmitted to the second repeater at the transmission frequency;
measure a received signal strength indication (RSSI) of a packet received in response to the probe packets; and adjust one of the power level or the transmission frequency in accordance with the measured RSSI.
a reception device receiving a wireless signal including one or more packets at a reception frequency;
a signal modification and detection device coupled to the reception device, the signal modification and detection device configured to modify a predetermined portion of the packet to thereby generate a modified wireless signal and to detect if a predetermined portion of the packet includes a modified signal pattern;
a transmission device coupled to the signal modification and detection device for transmitting the modified wireless signal to one of the second repeater, first wireless station, and second wireless station at a predetermined power level and a transmission frequency;
a processor controlling the reception device and the transmission device; and a memory coupled to the processor, the memory for storing a power adjustment routine for configuring the processor to:
generate probe packets to be transmitted to the second repeater at the transmission frequency;
measure a received signal strength indication (RSSI) of a packet received in response to the probe packets; and adjust one of the power level or the transmission frequency in accordance with the measured RSSI.
6. The first repeater of claim 5, wherein the signal modification and detection device coupled to the reception device comprises a notch processor configured to insert a notch pattern on the wireless signal to be transmitted and detect a notch pattern inserted on a wireless signal received from the second repeater.
7. The first repeater of claim 5, wherein the signal modification and detection device coupled to the reception device comprises:
a bi-phase modulation device configured to modulate a phase of the predetermined portion of the wireless signal; and a digital demodulator coupled to the reception device, the digital demodulator configured to determine if the wireless signal includes a modulated phase pattern as the modified portion.
a bi-phase modulation device configured to modulate a phase of the predetermined portion of the wireless signal; and a digital demodulator coupled to the reception device, the digital demodulator configured to determine if the wireless signal includes a modulated phase pattern as the modified portion.
8. A repeater operating within a wireless network, comprising:
a reception device configured to receive a wireless signal;
a detector configured to detect whether a received signal strength indication (RSSI) of the received wireless signal is greater than a predetermined threshold;
a digital demodulator configured to demodulate the wireless signal if the detected RSSI is greater than the predetermined threshold;
a signal modification device configured to modify a first few symbols of packets in a predetermined portion of the received wireless signal; and a transmission device configured to transmit the modified wireless signal to one or more of another repeater or a wireless station device, wherein the signal modification device includes a bi-phase modulator configured to modulate a phase of the first few symbols of packets in the predetermined portion of the wireless signal, further comprising a timing circuit coupled to the bi-phase modulator, the timing circuit configured to control an amount of time during which the bi-phase modulator modulates the phase of the first few symbols of packets in the predetermined portion of the wireless signal, the timing circuit being activated when the detected RSSI is greater than the predetermined threshold.
a reception device configured to receive a wireless signal;
a detector configured to detect whether a received signal strength indication (RSSI) of the received wireless signal is greater than a predetermined threshold;
a digital demodulator configured to demodulate the wireless signal if the detected RSSI is greater than the predetermined threshold;
a signal modification device configured to modify a first few symbols of packets in a predetermined portion of the received wireless signal; and a transmission device configured to transmit the modified wireless signal to one or more of another repeater or a wireless station device, wherein the signal modification device includes a bi-phase modulator configured to modulate a phase of the first few symbols of packets in the predetermined portion of the wireless signal, further comprising a timing circuit coupled to the bi-phase modulator, the timing circuit configured to control an amount of time during which the bi-phase modulator modulates the phase of the first few symbols of packets in the predetermined portion of the wireless signal, the timing circuit being activated when the detected RSSI is greater than the predetermined threshold.
9. The repeater recited in claim 8, wherein the bi-phase modulator is further configured to modulate the phase of the first few symbols of packets to have a unique signature recognizable by the other repeater upon receiving the modified wireless signal.
10. The repeater recited in claim 8, further comprising a surface acoustic wave filter coupled to the output of the bi-phase modulator and configured to remove spectral splattering from the modified wireless signal.
11. The repeater recited in claim 8, wherein the bi-phase modulator includes a transfer switch coupled to an amplifier on a signal path of the wireless signal.
12. The repeater recited in claim 8, wherein the digital demodulator is further configured to detect if a predetermined portion of the received wireless signal has gain modulation and not demodulate a substantial portion of the received wireless signal if the predetermined portion of the wireless signal received has gain modulation, thereby causing the repeater to not repeat a substantial portion of the wireless signal.
13. The repeater recited in claim 8, wherein the digital demodulator is further configured to not demodulate the received wireless signal if a predetermined portion of a preamble of the received wireless signal received has gain modulation and the digital demodulator is in a wireless local area network only configuration, thereby causing the repeater to not repeat a substantial portion of the wireless signal.
14. The repeater recited in claim 8, wherein the transmission device is configured to transmit the modified wireless signal at one or more of a frequency different from a reception frequency or a different power level if a preamble of the received wireless signal has phase modulation.
15. The repeater recited in claim 8, wherein the digital demodulator is further configured to determine if a preamble of the received wireless signal has phase modulation and to remove the phase modulation.
16. The repeater recited in claim 8, wherein the wireless signal includes one or more packets defined according to the Institute of Electrical and Electronics Engineers (IEEE) 802.11 standard and wherein the predetermined portion of the wireless signal is an initial portion of a preamble of the one or more packets.
17. The repeater recited in claim 16, wherein the initial portion of the preamble is a portion of the received wireless signal that is not recovered by the wireless station device.
18. The repeater recited in claim 16, wherein the initial portion of the preamble is a first four symbols of a packet in the received wireless signal.
19. The repeater recited in claim 16, wherein the modified wireless signal conforms to a spectral mask defined by the IEEE 802.11g standard.
20. The repeater recited in claim 8, wherein the signal modification device includes a notch processor configured to insert a notch pattern on the wireless signal to be transmitted and detect a notch pattern inserted on a wireless signal received from the other repeater.
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Families Citing this family (24)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US8498234B2 (en) * | 2002-06-21 | 2013-07-30 | Qualcomm Incorporated | Wireless local area network repeater |
US8885688B2 (en) | 2002-10-01 | 2014-11-11 | Qualcomm Incorporated | Control message management in physical layer repeater |
CA2667470A1 (en) * | 2006-10-26 | 2008-05-15 | Qualcomm Incorporated | Repeater techniques for multiple input multiple output utilizing beam formers |
WO2010126322A2 (en) * | 2009-04-29 | 2010-11-04 | 한국전자통신연구원 | Transmission power control method and device for cognitive radio device |
CN101902807B (en) * | 2010-07-05 | 2013-02-06 | 海能达通信股份有限公司 | Terminal of digital mobile wireless transferring system, method for adjusting transmission power thereof and system thereof |
US8942159B2 (en) | 2010-07-05 | 2015-01-27 | Hytera Communications Corp., Ltd. | Terminal in digital mobile radio relay system, transmission power regulation method and system thereof |
CN102143508A (en) * | 2010-12-06 | 2011-08-03 | 华为终端有限公司 | Upgrading method and upgrading device for wireless repeater |
US8626060B2 (en) * | 2011-04-14 | 2014-01-07 | Qualcomm, Incorporated | Beacon signals for repeaters within a wireless communications system |
ITMI20110756A1 (en) * | 2011-05-05 | 2012-11-06 | S Di G Moiraghi & C Soc Sa | RECEIVER OF SIGNALS IN RADIO FREQUENCY. |
US8532566B2 (en) | 2011-06-08 | 2013-09-10 | Andrew Llc | System and method for reducing desensitization of a base station transceiver for mobile wireless repeater systems |
US8649418B1 (en) | 2013-02-08 | 2014-02-11 | CBF Networks, Inc. | Enhancement of the channel propagation matrix order and rank for a wireless channel |
US8422540B1 (en) | 2012-06-21 | 2013-04-16 | CBF Networks, Inc. | Intelligent backhaul radio with zero division duplexing |
US9295022B2 (en) * | 2012-05-18 | 2016-03-22 | Comcast Cable Communications, LLC. | Wireless network supporting extended coverage of service |
US9179244B2 (en) * | 2012-08-31 | 2015-11-03 | Apple Inc. | Proximity and tap detection using a wireless system |
US20140105251A1 (en) * | 2012-10-16 | 2014-04-17 | Effigis Geo Solutions | Leakage detection in an all-digital cable distribution network |
CA2814303A1 (en) | 2013-04-26 | 2014-10-26 | Cellphone-Mate, Inc. | Apparatus and methods for radio frequency signal boosters |
CN104135316B (en) * | 2013-05-03 | 2017-11-21 | 中国移动通信集团公司 | A kind of via node |
US10334085B2 (en) * | 2015-01-29 | 2019-06-25 | Splunk Inc. | Facilitating custom content extraction from network packets |
US20170244497A1 (en) * | 2015-10-16 | 2017-08-24 | Solid RF Communication, Co., Ltd. | Detection of oscillations in signal amplifiers |
WO2017176840A1 (en) * | 2016-04-05 | 2017-10-12 | Wilson Electronics, Llc | Narrowband signal detection for network protection |
US10374698B2 (en) * | 2017-01-31 | 2019-08-06 | Wilson Electronics, Llc | Reducing oscillation in a signal booster |
US20180238574A1 (en) * | 2017-02-17 | 2018-08-23 | Johnson Controls Technology Company | Hvac system with wireless waveguide system |
US10862533B2 (en) * | 2018-01-04 | 2020-12-08 | Wilson Electronics, Llc | Line loss detection in a signal booster system |
US11233492B2 (en) * | 2019-06-05 | 2022-01-25 | Wilson Electronics, Llc | Power amplifier (PA)-filter output power tuning |
Family Cites Families (312)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3363250A (en) * | 1965-07-20 | 1968-01-09 | Jacobson Irving | Monitoring system for remote radio control |
US4001691A (en) * | 1975-01-30 | 1977-01-04 | Gruenberg Elliot | Communications relay system |
US4081752A (en) * | 1975-05-30 | 1978-03-28 | Sanyo Electric Co., Ltd. | Digital frequency synthesizer receiver |
US4204016A (en) | 1975-07-25 | 1980-05-20 | Chavannes Marc A | Reinforced paper products |
US4000467A (en) | 1975-10-24 | 1976-12-28 | Bell Telephone Laboratories, Incorporated | Automatic repeater stressing |
GB1545623A (en) | 1976-05-19 | 1979-05-10 | Elap | Transmission system and repeater stations therefor |
GB1590826A (en) | 1976-09-21 | 1981-06-10 | Post Office | Level stabilisers |
US4368541A (en) * | 1980-06-30 | 1983-01-11 | Evans Robert M | Multiplexing arrangement for a plurality of voltage controlled filters |
US4334323A (en) | 1980-09-08 | 1982-06-08 | Zenith Radio Corporation | Self tracking tuner |
FR2526609A1 (en) * | 1982-05-04 | 1983-11-10 | Thomson Csf | MULTI-PORT SIGNAL RECEIVER PROTECTS DISTURBING SIGNALS |
CA1238086A (en) * | 1984-08-17 | 1988-06-14 | Joseph P. Mcgeehan | Data transmission using a transparent tone-in band system |
CA1235751A (en) | 1985-01-09 | 1988-04-26 | Junji Namiki | One frequency repeater for a digital microwave radio system with cancellation of transmitter-to-receiver interference |
FR2592256B1 (en) | 1985-12-20 | 1988-02-12 | Trt Telecom Radio Electr | DEVICE FOR CONTROLLING THE TRANSMIT POWER OF A RADIO BEAM |
US4783843A (en) | 1986-05-23 | 1988-11-08 | Peninsula Engineering Group, Inc. | Split band filter for cellular mobile radio |
US4723302A (en) * | 1986-08-05 | 1988-02-02 | A. C. Nielsen Company | Method and apparatus for determining channel reception of a receiver |
DE3884653T2 (en) | 1987-04-03 | 1994-02-03 | Fujitsu Ltd | Method and device for the vapor deposition of diamond. |
US4820568A (en) * | 1987-08-03 | 1989-04-11 | Allied-Signal Inc. | Composite and article using short length fibers |
US5023930A (en) * | 1987-08-03 | 1991-06-11 | Orion Industries, Inc. | Booster with detectable boost operation |
US4922259A (en) | 1988-02-04 | 1990-05-01 | Mcdonnell Douglas Corporation | Microstrip patch antenna with omni-directional radiation pattern |
US5095528A (en) * | 1988-10-28 | 1992-03-10 | Orion Industries, Inc. | Repeater with feedback oscillation control |
FR2646977B1 (en) | 1989-05-10 | 1994-07-29 | Thomson Csf | METHOD AND DEVICE FOR TRANSMITTING INFORMATION BETWEEN RADIO TRANSCEIVERS OF THE SAME NETWORK OPERATING IN FREQUENCY ESCAPE |
US5220562A (en) | 1989-05-12 | 1993-06-15 | Hitachi, Ltd. | Bridge apparatus and a communication system between networks using the bridge apparatus |
US5485486A (en) * | 1989-11-07 | 1996-01-16 | Qualcomm Incorporated | Method and apparatus for controlling transmission power in a CDMA cellular mobile telephone system |
US5349463A (en) | 1990-08-17 | 1994-09-20 | Victor Company Of Japan | Optical radio repeater with signal quality detection |
NZ239733A (en) | 1990-09-21 | 1994-04-27 | Ericsson Ge Mobile Communicat | Mobile telephone diversity reception with predetect signal combination |
JP2591338B2 (en) * | 1990-11-20 | 1997-03-19 | 松下電器産業株式会社 | Sub-sampling device, interpolation device, transmitting device, receiving device, and recording medium |
EP0495575B1 (en) | 1991-01-18 | 1997-08-06 | National Semiconductor Corporation | Repeater interface controller |
GB9102220D0 (en) | 1991-02-01 | 1991-03-20 | British Telecomm | Method and apparatus for decoding video signals |
US5280480A (en) * | 1991-02-21 | 1994-01-18 | International Business Machines Corporation | Source routing transparent bridge |
US5678198A (en) | 1991-05-22 | 1997-10-14 | Southwestern Bell Technology Resources, Inc. | System for controlling signal level at both ends of a transmission link, based upon a detected value |
JPH0530000A (en) | 1991-07-18 | 1993-02-05 | Fujitsu Ltd | Mobile body communication system |
US5341364A (en) | 1992-06-02 | 1994-08-23 | At&T Bell Laboratories | Distributed switching in bidirectional multiplex section-switched ringtransmission systems |
GB2268374A (en) | 1992-06-23 | 1994-01-05 | Ibm | Network addressing |
US5377255A (en) | 1992-07-14 | 1994-12-27 | Pcs Microcell International Inc. | RF repeaters for time division duplex cordless telephone systems |
US5408618A (en) * | 1992-07-31 | 1995-04-18 | International Business Machines Corporation | Automatic configuration mechanism |
GB2272599A (en) | 1992-11-12 | 1994-05-18 | Nokia Telecommunications Oy | A method of cellular radio communication and a cellular radio system for use in such method |
AU672054B2 (en) | 1992-12-30 | 1996-09-19 | Radio Communication Systems Ltd. | Bothway RF repeater for personal communications systems |
US5333175A (en) | 1993-01-28 | 1994-07-26 | Bell Communications Research, Inc. | Method and apparatus for dynamic power control in TDMA portable radio systems |
US5371734A (en) | 1993-01-29 | 1994-12-06 | Digital Ocean, Inc. | Medium access control protocol for wireless network |
JPH06260866A (en) * | 1993-03-04 | 1994-09-16 | Mitsubishi Electric Corp | Automatic output power control circuit device |
FR2703199B1 (en) * | 1993-03-26 | 1995-06-02 | Matra Communication | Radio transmission method using repeating spectrum inverting stations. |
JPH06291697A (en) | 1993-03-31 | 1994-10-18 | Matsushita Electric Ind Co Ltd | Transmitter receiver |
US5373503A (en) | 1993-04-30 | 1994-12-13 | Information Technology, Inc. | Group randomly addressed polling method |
US5515376A (en) | 1993-07-19 | 1996-05-07 | Alantec, Inc. | Communication apparatus and methods |
FR2708814B1 (en) | 1993-07-30 | 1995-09-01 | Alcatel Mobile Comm France | Method for covering the shadow areas of a radiocommunication network, and radio repeater for implementing this method. |
EP0668662A4 (en) | 1993-08-06 | 1997-02-12 | Nippon Telegraph & Telephone | Receiver and repeater for spread spectrum communication. |
JP3337795B2 (en) | 1993-12-10 | 2002-10-21 | 富士通株式会社 | Relay device |
US5471642A (en) | 1994-01-28 | 1995-11-28 | Palmer; James K. | Re-broadcast system for a plurality of AM signals |
FI108098B (en) | 1994-03-03 | 2001-11-15 | Nokia Networks Oy | Method for controlling a subscriber station, radio system and subscriber station operating on a direct channel |
US5519619A (en) | 1994-03-14 | 1996-05-21 | Motorola, Inc. | Route planning method for hierarchical map routing and apparatus therefor |
US5648984A (en) | 1994-08-10 | 1997-07-15 | Alcatel Networks Systems, Inc. | Multidirectional repeater for data transmission between electrically isolated and/or physically different signal transmission media |
US5832035A (en) * | 1994-09-20 | 1998-11-03 | Time Domain Corporation | Fast locking mechanism for channelized ultrawide-band communications |
US5608755A (en) * | 1994-10-14 | 1997-03-04 | Rakib; Selim | Method and apparatus for implementing carrierless amplitude/phase encoding in a network |
US5873028A (en) | 1994-10-24 | 1999-02-16 | Ntt Mobile Communications Network Inc. | Transmission power control apparatus and method in a mobile communication system |
US5727033A (en) | 1994-11-30 | 1998-03-10 | Lucent Technologies Inc. | Symbol error based power control for mobile telecommunication system |
MY123040A (en) | 1994-12-19 | 2006-05-31 | Salbu Res And Dev Proprietary Ltd | Multi-hop packet radio networks |
US5684801A (en) | 1994-12-30 | 1997-11-04 | Lucent Technologies | Portable wireless local area network |
US5654979A (en) | 1995-01-13 | 1997-08-05 | Qualcomm Incorporated | Cell site demodulation architecture for a spread spectrum multiple access communication systems |
GB9500825D0 (en) | 1995-01-17 | 1995-03-08 | Macnamee Robert J G | Radio communications systems with repeaters |
JPH08242475A (en) * | 1995-03-06 | 1996-09-17 | Toshiba Corp | Method for call reception and call transmission for private branch of exchange |
US5651010A (en) * | 1995-03-16 | 1997-07-22 | Bell Atlantic Network Services, Inc. | Simultaneous overlapping broadcasting of digital programs |
JP3358148B2 (en) * | 1995-03-29 | 2002-12-16 | ソニー株式会社 | Communication system and method and receiver |
GB2299494B (en) * | 1995-03-30 | 1999-11-03 | Northern Telecom Ltd | Communications Repeater |
MY121893A (en) | 1995-04-28 | 2006-03-31 | Qualcomm Inc | Method and apparatus for providing variable rate data in a communications system using statistical multiplexing. |
US6535732B1 (en) * | 1995-05-04 | 2003-03-18 | Interwave Communications International, Ltd. | Cellular network having a concentrated base transceiver station and a plurality of remote transceivers |
US6101400A (en) | 1997-08-20 | 2000-08-08 | Interwave Communications, Inc. | Methods and apparatus for improved base station transceivers |
CN1043116C (en) * | 1995-05-08 | 1999-04-21 | 北京海淀三足通讯技术公司 | Two-way literal mobile communication system |
US5784683A (en) | 1995-05-16 | 1998-07-21 | Bell Atlantic Network Services, Inc. | Shared use video processing systems for distributing program signals from multiplexed digitized information signals |
US5697052A (en) | 1995-07-05 | 1997-12-09 | Treatch; James E. | Cellular specialized mobile radio system |
US5754540A (en) | 1995-07-18 | 1998-05-19 | Macronix International Co., Ltd. | Expandable integrated circuit multiport repeater controller with multiple media independent interfaces and mixed media connections |
US5890055A (en) * | 1995-07-28 | 1999-03-30 | Lucent Technologies Inc. | Method and system for connecting cells and microcells in a wireless communications network |
US5745846A (en) * | 1995-08-07 | 1998-04-28 | Lucent Technologies, Inc. | Channelized apparatus for equalizing carrier powers of multicarrier signal |
JP2755241B2 (en) | 1995-08-25 | 1998-05-20 | 住友電気工業株式会社 | Oscillation detection device for wireless repeater and wireless repeater to which this device is applied |
US6108364A (en) | 1995-08-31 | 2000-08-22 | Qualcomm Incorporated | Time division duplex repeater for use in a CDMA system |
US6128512A (en) | 1995-09-06 | 2000-10-03 | Cisco Systems, Inc. | Cellular communication system with dedicated repeater channels |
CN1084555C (en) | 1995-10-26 | 2002-05-08 | Ntt移动通信网株式会社 | Booster |
US6005884A (en) | 1995-11-06 | 1999-12-21 | Ems Technologies, Inc. | Distributed architecture for a wireless data communications system |
US6047165A (en) | 1995-11-14 | 2000-04-04 | Harris Corporation | Wireless, frequency-agile spread spectrum ground link-based aircraft data communication system |
JP3406443B2 (en) | 1995-12-08 | 2003-05-12 | 日本ビクター株式会社 | Wireless transmission equipment |
US5771174A (en) | 1995-12-21 | 1998-06-23 | Measurex Corporation | Distributed intelligence actuator controller with peer-to-peer actuator communication |
US5884181A (en) * | 1996-01-19 | 1999-03-16 | Bell Communications Research, Inc. | Interference reduction in shared-frequency wireless communication systems |
KR100188692B1 (en) | 1996-01-20 | 1999-06-01 | 윤종용 | Digital filter |
US5767788A (en) | 1996-03-19 | 1998-06-16 | Ness; James C. | Computer aided dispatch and locator cellular system |
US5764636A (en) | 1996-03-28 | 1998-06-09 | Cisco Technology, Inc. | Color blocking logic mechanism for a high-performance network switch |
JPH09284509A (en) | 1996-04-10 | 1997-10-31 | Canon Inc | Picture processor |
US5883884A (en) * | 1996-04-22 | 1999-03-16 | Roger F. Atkinson | Wireless digital communication system having hierarchical wireless repeaters with autonomous hand-off |
JP3039402B2 (en) | 1996-12-05 | 2000-05-08 | 日本電気株式会社 | Transmission power control device for mobile communication system |
US6774685B2 (en) * | 1996-05-13 | 2004-08-10 | Micron Technology, Inc. | Radio frequency data communications device |
US6130602A (en) * | 1996-05-13 | 2000-10-10 | Micron Technology, Inc. | Radio frequency data communications device |
US5930230A (en) | 1996-05-28 | 1999-07-27 | Qualcomm Incorporated | High data rate CDMA wireless communication system |
SE510569C2 (en) | 1996-05-31 | 1999-06-07 | Allgon Ab | Variable bandwidth repeater |
US5794145A (en) | 1996-06-07 | 1998-08-11 | Telxon Corporation | Mobile device multiband antenna system |
DE69729784T2 (en) | 1996-06-27 | 2005-06-23 | Ntt Docomo, Inc. | ARRANGEMENT FOR TRANSMISSION CONTROL |
US6215982B1 (en) * | 1996-06-28 | 2001-04-10 | Cisco Systems, Inc. | Wireless communication method and device with auxiliary receiver for selecting different channels |
JPH1022756A (en) * | 1996-07-04 | 1998-01-23 | Mitsubishi Electric Corp | Radio transmitter and its transmission control method |
US5857144A (en) * | 1996-08-09 | 1999-01-05 | Ericsson, Inc. | In-band vehicular repeater for trunked radio system |
FR2753589B1 (en) * | 1996-09-17 | 1998-10-09 | Alcatel Espace | RELAYS FOR RADIOCOMMUNICATION SYSTEM |
US5875179A (en) * | 1996-10-29 | 1999-02-23 | Proxim, Inc. | Method and apparatus for synchronized communication over wireless backbone architecture |
JP3308835B2 (en) | 1996-12-06 | 2002-07-29 | 株式会社日立製作所 | Wireless communication system |
CA2224035A1 (en) | 1996-12-19 | 1998-06-19 | J. Leland Langston | Repeater node network system and method |
US6222503B1 (en) * | 1997-01-10 | 2001-04-24 | William Gietema | System and method of integrating and concealing antennas, antenna subsystems and communications subsystems |
FR2760167B1 (en) | 1997-02-21 | 2000-08-04 | Sagem | RADIOTELEPHONY METHOD BETWEEN A BASE STATION AND A MOBILE TELEPHONE THROUGH A REPEATER |
US6584144B2 (en) | 1997-02-24 | 2003-06-24 | At&T Wireless Services, Inc. | Vertical adaptive antenna array for a discrete multitone spread spectrum communications system |
JPH10247874A (en) * | 1997-03-04 | 1998-09-14 | Kokusai Electric Co Ltd | Time-division duplex system portable telephone repeater |
US5963846A (en) | 1997-03-31 | 1999-10-05 | Motorola, Inc. | Method and system for repeating pages |
KR19980063664U (en) | 1997-04-18 | 1998-11-25 | 임경춘 | Lubricant supply structure of shift fork for manual transmission |
CA2463381C (en) | 1997-05-14 | 2011-11-22 | Qualcomm Incorporated | A subscriber unit and method for use in a wireless communication system |
JP3123467B2 (en) * | 1997-06-18 | 2001-01-09 | 日本電気株式会社 | bridge |
US6014380A (en) * | 1997-06-30 | 2000-01-11 | Sun Microsystems, Inc. | Mechanism for packet field replacement in a multi-layer distributed network element |
JPH1141131A (en) | 1997-07-15 | 1999-02-12 | Toshiba Corp | Radio communication device |
US6061548A (en) | 1997-07-17 | 2000-05-09 | Metawave Communications Corporation | TDMA repeater eliminating feedback |
US5959968A (en) | 1997-07-30 | 1999-09-28 | Cisco Systems, Inc. | Port aggregation protocol |
WO1999007077A2 (en) * | 1997-07-31 | 1999-02-11 | Stanford Syncom Inc. | Means and method for a synchronous network communications system |
US6484012B1 (en) * | 1997-08-04 | 2002-11-19 | Wireless Facilities, Inc. | Inter-band communication repeater system |
US6574211B2 (en) | 1997-11-03 | 2003-06-03 | Qualcomm Incorporated | Method and apparatus for high rate packet data transmission |
US6404775B1 (en) | 1997-11-21 | 2002-06-11 | Allen Telecom Inc. | Band-changing repeater with protocol or format conversion |
US6377612B1 (en) * | 1998-07-30 | 2002-04-23 | Qualcomm Incorporated | Wireless repeater using polarization diversity in a wireless communications system |
US6128729A (en) | 1997-12-16 | 2000-10-03 | Hewlett-Packard Company | Method and system for automatic configuration of network links to attached devices |
US6188694B1 (en) * | 1997-12-23 | 2001-02-13 | Cisco Technology, Inc. | Shared spanning tree protocol |
US6032194A (en) | 1997-12-24 | 2000-02-29 | Cisco Technology, Inc. | Method and apparatus for rapidly reconfiguring computer networks |
US6202114B1 (en) * | 1997-12-31 | 2001-03-13 | Cisco Technology, Inc. | Spanning tree with fast link-failure convergence |
JPH11220430A (en) | 1998-01-30 | 1999-08-10 | Matsushita Electric Ind Co Ltd | Diversity communication equipment and diversity reception method |
JPH11266180A (en) | 1998-03-18 | 1999-09-28 | Fujitsu Ltd | Array antenna system for radio base station |
US6944139B1 (en) | 1998-03-27 | 2005-09-13 | Worldspace Management Corporation | Digital broadcast system using satellite direct broadcast and terrestrial repeater |
US6339694B1 (en) * | 1998-03-30 | 2002-01-15 | Airnet Communications Corporation | Method and apparatus employing automatic RF muting and wireless remote control of RF downlink transmission for a wireless repeater |
US6138261A (en) * | 1998-04-29 | 2000-10-24 | Trw Inc. | Concatenated coding system for satellite communications |
US6400968B1 (en) * | 1998-05-04 | 2002-06-04 | Conexant Systems, Inc. | System and method for extending the range of a base unit |
JP2000031877A (en) | 1998-07-09 | 2000-01-28 | Sharp Corp | Mobile communication system |
EP1101294B1 (en) | 1998-07-28 | 2010-12-15 | Samsung Electronics Co., Ltd. | Gated transmission in control hold state in cdma communication system |
US6304575B1 (en) | 1998-08-31 | 2001-10-16 | Cisco Technology, Inc. | Token ring spanning tree protocol |
JP2000082983A (en) | 1998-09-03 | 2000-03-21 | Kokusai Electric Co Ltd | Radio repeater amplifier device |
US6252865B1 (en) | 1998-10-02 | 2001-06-26 | Qualcomm, Inc. | Methods and apparatuses for fast power control of signals transmitted on a multiple access channel |
KR100547713B1 (en) * | 1998-10-20 | 2006-03-23 | 삼성전자주식회사 | Variable Channel Device for Wideband Code Division Multiple Access System |
US6121932A (en) * | 1998-11-03 | 2000-09-19 | Motorola, Inc. | Microstrip antenna and method of forming same |
CN1285921A (en) | 1998-11-11 | 2001-02-28 | 三星电子株式会社 | Digital correlator for receptor of signals from satellite radio-navigation systems |
SE520836C3 (en) | 1998-11-18 | 2003-10-01 | Saab Ab | Repeater interference transmitter and sleeve arrangement for the same |
US6088570A (en) | 1998-11-24 | 2000-07-11 | Airnet Communications Corporation | Method and apparatus employing delay elements in multiple diversity paths of a wireless system repeater translator to allow for selective diversity and automatic level control in a time-division multiple access system |
SG87784A1 (en) * | 1998-12-09 | 2002-04-16 | Kent Ridge Digital Labs | Csma/cd wireless lan |
US6628624B1 (en) | 1998-12-09 | 2003-09-30 | Cisco Technology, Inc. | Value-added features for the spanning tree protocol |
JP3484670B2 (en) | 1999-02-15 | 2004-01-06 | 日本電気エンジニアリング株式会社 | Satellite communication system |
KR20010111268A (en) | 1999-02-25 | 2001-12-17 | 버클리 컨셉 리서치 코포레이션 | Multichannel Distributed Wireless Repeater Network |
JP2000269873A (en) | 1999-03-12 | 2000-09-29 | Kokusai Electric Co Ltd | Radio relay amplifier |
JP2000286652A (en) | 1999-03-31 | 2000-10-13 | Harada Ind Co Ltd | Controller |
GB2349294B (en) | 1999-04-19 | 2001-07-11 | Marconi Comm Ltd | Communications system |
US6304563B1 (en) | 1999-04-23 | 2001-10-16 | Qualcomm Incorporated | Method and apparatus for processing a punctured pilot channel |
US6163276A (en) | 1999-05-17 | 2000-12-19 | Cellnet Data Systems, Inc. | System for remote data collection |
GB2351420A (en) | 1999-06-23 | 2000-12-27 | Motorola Ltd | Power control in a radio communication system |
EP1063789B1 (en) * | 1999-06-23 | 2007-08-01 | Sony Deutschland GmbH | Transmit and receiving antenna diversity |
JP2001016152A (en) | 1999-06-30 | 2001-01-19 | Mitsubishi Electric Corp | Wireless repeater |
US6480788B2 (en) | 1999-07-12 | 2002-11-12 | Eagle-Eye, Inc. | System and method for fast acquisition reporting using communication satellite range measurement |
US6934511B1 (en) | 1999-07-20 | 2005-08-23 | Andrew Corporation | Integrated repeater |
WO2001052447A2 (en) | 2000-01-14 | 2001-07-19 | Andrew Corporation | Repeaters for wireless communication systems |
JP2001111575A (en) | 1999-08-03 | 2001-04-20 | Matsushita Electric Ind Co Ltd | Repeater device for converting radio lan cross channel and radio terminal device |
US6690657B1 (en) * | 2000-02-25 | 2004-02-10 | Berkeley Concept Research Corporation | Multichannel distributed wireless repeater network |
US6370185B1 (en) * | 1999-08-10 | 2002-04-09 | Airnet Communications Corporation | Translating repeater system with improved backhaul efficiency |
JP2001136115A (en) | 1999-11-01 | 2001-05-18 | Mitsubishi Electric Corp | Method for eliminating sneak-path wave for antenna system for relay station |
US6285863B1 (en) | 1999-11-24 | 2001-09-04 | Lucent Technologies Inc. | System and method for providing automatic gain control with high dynamic range |
US6718160B2 (en) * | 1999-12-29 | 2004-04-06 | Airnet Communications Corp. | Automatic configuration of backhaul and groundlink frequencies in a wireless repeater |
AU2001227681A1 (en) | 2000-01-10 | 2001-07-31 | Airnet Communications Corporation | Packet based backhaul channel configuration for a wireless repeater |
US6664932B2 (en) | 2000-01-12 | 2003-12-16 | Emag Technologies, Inc. | Multifunction antenna for wireless and telematic applications |
US6888809B1 (en) | 2000-01-13 | 2005-05-03 | Lucent Technologies Inc. | Space-time processing for multiple-input, multiple-output, wireless systems |
JP2001217896A (en) | 2000-01-31 | 2001-08-10 | Matsushita Electric Works Ltd | Wireless data communication system |
ES2160087B1 (en) | 2000-02-18 | 2003-03-01 | Mier Comunicaciones S A | PROCEDURE FOR REPETITION OF SIGNALS IN INSOFREQUENCY AND REPEATER OF SIGNS IN ISOFREQUENCY. |
JP2001244864A (en) | 2000-02-29 | 2001-09-07 | Hitachi Ltd | Radio repeating system |
US6493331B1 (en) | 2000-03-30 | 2002-12-10 | Qualcomm Incorporated | Method and apparatus for controlling transmissions of a communications systems |
US7703107B2 (en) * | 2000-04-06 | 2010-04-20 | Infineon Technologies Ag | Virtual machine interface for hardware reconfigurable and software programmable processors |
US6697988B2 (en) * | 2000-05-24 | 2004-02-24 | Samsung Electronics Co., Ltd. | Data transmission apparatus and method for an HARQ data communication system |
EP1830488A1 (en) * | 2000-06-05 | 2007-09-05 | Sony Deutschland GmbH | Indoor wireless communication system using active reflector |
US7103344B2 (en) | 2000-06-08 | 2006-09-05 | Menard Raymond J | Device with passive receiver |
JP2001357480A (en) | 2000-06-12 | 2001-12-26 | Matsushita Electric Ind Co Ltd | Emergency informing equipment |
US20010054060A1 (en) | 2000-06-16 | 2001-12-20 | Fillebrown Lisa A. | Personal wireless network |
US6766113B1 (en) | 2000-06-16 | 2004-07-20 | Lucent Technologies Inc. | Control channel processor and switching mechanism |
US6501955B1 (en) | 2000-06-19 | 2002-12-31 | Intel Corporation | RF signal repeater, mobile unit position determination system using the RF signal repeater, and method of communication therefor |
US6888881B1 (en) | 2000-06-20 | 2005-05-03 | Mitsubishi Denki Kabushiki Kaisha | Repeater |
US6331792B1 (en) | 2000-06-30 | 2001-12-18 | Conexant Systems, Inc. | Circuit and method for unlimited range frequency acquisition |
US6473131B1 (en) | 2000-06-30 | 2002-10-29 | Stmicroelectronics, Inc. | System and method for sampling an analog signal level |
US6574198B1 (en) | 2000-07-06 | 2003-06-03 | Ericsson Inc. | Systems and methods for maintaining a signaling link in a communications network |
US6452910B1 (en) | 2000-07-20 | 2002-09-17 | Cadence Design Systems, Inc. | Bridging apparatus for interconnecting a wireless PAN and a wireless LAN |
JP3541787B2 (en) * | 2000-07-26 | 2004-07-14 | 株式会社デンソー | Multiplex communication system |
US7366103B2 (en) | 2000-08-18 | 2008-04-29 | Nortel Networks Limited | Seamless roaming options in an IEEE 802.11 compliant network |
US6778612B1 (en) | 2000-08-18 | 2004-08-17 | Lucent Technologies Inc. | Space-time processing for wireless systems with multiple transmit and receive antennas |
AU2001288828A1 (en) * | 2000-09-14 | 2002-03-26 | Ensemble Communications, Inc. | A system and method for wireless communication in a frequency division duplexingregion |
US7710503B2 (en) * | 2000-09-25 | 2010-05-04 | Thomson Licensing | Apparatus and method for optimizing the level of RF signals based upon the information stored on a memory |
US6563468B2 (en) | 2001-04-27 | 2003-05-13 | Tyco Electronics Logistics Ag | Omni directional antenna with multiple polarizations |
JP3596452B2 (en) | 2000-09-28 | 2004-12-02 | 日本電信電話株式会社 | Wireless repeater |
US6539204B1 (en) * | 2000-09-29 | 2003-03-25 | Mobilian Corporation | Analog active cancellation of a wireless coupled transmit signal |
US7050452B2 (en) | 2000-10-06 | 2006-05-23 | Cognio, Inc. | Systems and methods for interference mitigation among multiple WLAN protocols |
CA2323881A1 (en) * | 2000-10-18 | 2002-04-18 | Dps Wireless Inc. | Adaptive personal repeater |
KR100401186B1 (en) | 2000-10-20 | 2003-10-10 | 삼성전자주식회사 | Apparatus and method for determining a data rate of packet data in mobile communication system |
US6807165B2 (en) | 2000-11-08 | 2004-10-19 | Meshnetworks, Inc. | Time division protocol for an ad-hoc, peer-to-peer radio network having coordinating channel access to shared parallel data channels with separate reservation channel |
KR100464485B1 (en) * | 2000-11-09 | 2004-12-31 | 엘지전자 주식회사 | A method and a device of transmitting high-speed packet data |
US6985516B1 (en) * | 2000-11-27 | 2006-01-10 | Qualcomm Incorporated | Method and apparatus for processing a received signal in a communications system |
WO2002052875A2 (en) | 2000-12-27 | 2002-07-04 | Ensemble Communications, Inc. | Adaptive call admission control for use in a wireless communication system |
TWM249366U (en) | 2001-01-02 | 2004-11-01 | Z Com Inc | Radio signal detection device of wireless local area network |
WO2002058414A1 (en) | 2001-01-20 | 2002-07-25 | Samsung Electronics Co., Ltd | System and method for remotely controlling a mobile terminal |
US7027418B2 (en) * | 2001-01-25 | 2006-04-11 | Bandspeed, Inc. | Approach for selecting communications channels based on performance |
JP4218213B2 (en) * | 2001-01-26 | 2009-02-04 | パナソニック電工株式会社 | Radio remote control |
US20020109585A1 (en) | 2001-02-15 | 2002-08-15 | Sanderson Lelon Wayne | Apparatus, method and system for range extension of a data communication signal on a high voltage cable |
US7113745B2 (en) | 2001-02-21 | 2006-09-26 | Ericsson Inc. | Method to achieve diversity in a communication network |
JP2002271255A (en) | 2001-03-12 | 2002-09-20 | Toshiba Digital Media Engineering Corp | Repeater equipment and interexchange method |
JP2002281042A (en) * | 2001-03-15 | 2002-09-27 | Toshiba Corp | Method for preventing communication data loop of radio transmission system |
US7065036B1 (en) | 2001-03-19 | 2006-06-20 | Cisco Systems Wireless Networking (Australia) Pty Limited | Method and apparatus to reduce latency in a data network wireless radio receiver |
US7088734B2 (en) | 2001-03-27 | 2006-08-08 | Motorola, Inc. | Slot format and method for increasing random access opportunities in a wireless communication system |
EP1382217B1 (en) * | 2001-04-24 | 2010-04-28 | QUALCOMM Incorporated | Method and apparatus for estimating the position of a terminal based on identification codes for transmission sources |
JP3943859B2 (en) | 2001-05-01 | 2007-07-11 | 株式会社エヌ・ティ・ティ・ドコモ | Mobile communication system, mobile communication method, and mobile station |
US7272137B2 (en) * | 2001-05-14 | 2007-09-18 | Nortel Networks Limited | Data stream filtering apparatus and method |
US7027770B2 (en) * | 2001-05-22 | 2006-04-11 | Andrew Corporation | Repeater for customer premises |
US7167526B2 (en) * | 2001-06-07 | 2007-01-23 | National Univ. Of Singapore | Wireless communication apparatus and method |
US7594010B2 (en) | 2001-06-28 | 2009-09-22 | King's London College | Virtual antenna array |
US6934555B2 (en) | 2001-06-29 | 2005-08-23 | Telefonaktiebolaget Lm Ericsson (Publ) | Software analysis tool for CDMA system |
US20030026363A1 (en) * | 2001-07-31 | 2003-02-06 | Jan Stoter | Adaptive automatic gain control |
DE60124708T2 (en) * | 2001-09-14 | 2007-09-13 | Motorola, Inc., Schaumburg | Method for improving the communication capability in a wireless telecommunication system |
US7123670B2 (en) | 2001-09-24 | 2006-10-17 | Atheros Communications, Inc. | Fine frequency offset estimation and calculation and use to improve communication system performance |
JPWO2003037027A1 (en) | 2001-10-18 | 2005-02-17 | 富士通株式会社 | Mobile communication system and communication method for mobile communication system |
DE60235847D1 (en) | 2001-11-20 | 2010-05-12 | Qualcomm Inc | Reverse link power controlled amplifier unit |
JP2003174394A (en) | 2001-12-06 | 2003-06-20 | Hitachi Kokusai Electric Inc | Communication unit |
US7406647B2 (en) | 2001-12-06 | 2008-07-29 | Pulse-Link, Inc. | Systems and methods for forward error correction in a wireless communication network |
JP4052835B2 (en) | 2001-12-28 | 2008-02-27 | 株式会社日立製作所 | Wireless transmission system for multipoint relay and wireless device used therefor |
JP2003244050A (en) | 2002-02-14 | 2003-08-29 | Hitachi Cable Ltd | Method for controlling transmission power for repeater |
US6904266B1 (en) | 2002-02-19 | 2005-06-07 | Navini Networks, Inc. | Wireless enhancer using a switch matrix |
US7050758B2 (en) | 2002-02-28 | 2006-05-23 | Nortel Networks Limited | Self-configuring repeater system and method |
US7315573B2 (en) * | 2002-02-28 | 2008-01-01 | Texas Instruments Incorporated | Channel monitoring for improved parameter selection in a communication system |
US7058071B1 (en) | 2002-03-04 | 2006-06-06 | Cisco Systems Wireless Networking (Australia) Pty Limited | Method and apparatus using pipelined execution data sets for processing transmission frame sequences conforming to a wireless network MAC protocol |
US6781544B2 (en) | 2002-03-04 | 2004-08-24 | Cisco Technology, Inc. | Diversity antenna for UNII access point |
US6990313B1 (en) * | 2002-03-14 | 2006-01-24 | Sprint Communications Company L.P. | Wireless repeater with intelligent signal display |
JP3799282B2 (en) * | 2002-03-22 | 2006-07-19 | Necインフロンティア株式会社 | Wireless LAN base station capable of automatic wireless channel alignment |
US20030185163A1 (en) | 2002-03-27 | 2003-10-02 | Bertonis James G. | System and method for wireless cable data transmission |
EP1359684A1 (en) | 2002-04-30 | 2003-11-05 | Motorola Energy Systems Inc. | Wireless transmission using an adaptive transmit antenna array |
KR100827140B1 (en) * | 2002-05-03 | 2008-05-02 | 삼성전자주식회사 | Apparatus for generating reception/transmission reference timing in mobile communication terminal and method thereof |
CN1186401C (en) | 2002-05-17 | 2005-01-26 | 中山大学 | Nano diamond particle surface treatment method |
JP2003332963A (en) * | 2002-05-17 | 2003-11-21 | Toshiba Corp | Radio communication system and apparatus thereof |
US7113498B2 (en) * | 2002-06-05 | 2006-09-26 | Broadcom Corporation | Virtual switch |
US7120930B2 (en) | 2002-06-13 | 2006-10-10 | Nvidia Corporation | Method and apparatus for control of security protocol negotiation |
US8498234B2 (en) | 2002-06-21 | 2013-07-30 | Qualcomm Incorporated | Wireless local area network repeater |
US20030235170A1 (en) | 2002-06-21 | 2003-12-25 | Trainin Solomon B. | Method, apparatus, and system for distributed access points for wireless local area network (LAN) |
US20040157551A1 (en) | 2002-06-21 | 2004-08-12 | Tantivy Communications, Inc | Repeater for extending range of time division duplex communication system |
AU2003247575A1 (en) | 2002-06-21 | 2004-01-06 | Ipr Licensing, Inc. | Repeater for extending range of time division duplex communication system |
US20040047335A1 (en) * | 2002-06-21 | 2004-03-11 | Proctor James Arthur | Wireless local area network extension using existing wiring and wireless repeater module(s) |
US7058368B2 (en) | 2002-06-27 | 2006-06-06 | Nortel Networks Limited | Adaptive feedforward noise cancellation circuit |
US7355993B2 (en) | 2002-06-27 | 2008-04-08 | Adkins Keith L | Method and apparatus for forward link gain control in a power controlled repeater |
JP2004056210A (en) | 2002-07-16 | 2004-02-19 | Matsushita Electric Ind Co Ltd | Mobile communication system, base station apparatus, and mobile station apparatus |
US20040121648A1 (en) * | 2002-07-26 | 2004-06-24 | V-Squared Networks | Network device for communicating information |
KR100702746B1 (en) * | 2002-08-20 | 2007-04-03 | 엘지전자 주식회사 | Method and apparatus for managing power of wireless local area network module in computer system |
US7590145B2 (en) | 2002-09-17 | 2009-09-15 | Scientific-Atlanta, Inc. | Multiplexing octets from a data flow over MPEG packets |
US6788256B2 (en) * | 2002-09-19 | 2004-09-07 | Cingular Wireless, Llc | Concealed antenna assembly |
EP1547269A4 (en) | 2002-10-01 | 2006-11-08 | Widefi Inc | Wireless local area network with repeater for enhancing network coverage |
WO2004038958A1 (en) | 2002-10-24 | 2004-05-06 | Widefi, Inc. | Wireless local area network repeater with in-band control channel |
US8885688B2 (en) * | 2002-10-01 | 2014-11-11 | Qualcomm Incorporated | Control message management in physical layer repeater |
AU2003274992A1 (en) * | 2002-10-11 | 2004-05-04 | Widefi, Inc. | Reducing loop effects in a wireless local area network repeater |
US8078100B2 (en) | 2002-10-15 | 2011-12-13 | Qualcomm Incorporated | Physical layer repeater with discrete time filter for all-digital detection and delay generation |
EP1604468B1 (en) | 2002-10-15 | 2008-07-23 | Qualcomm Incorporated | Wireless local area network repeater with automatic gain control for extending network coverage |
US7230935B2 (en) | 2002-10-24 | 2007-06-12 | Widefi, Inc. | Physical layer repeater with selective use of higher layer functions based on network operating conditions |
KR20050086572A (en) | 2002-11-15 | 2005-08-30 | 위데피, 인코포레이티드 | Wireless local area network repeater with detection |
GB2411797B (en) | 2002-12-16 | 2006-03-01 | Widefi Inc | Improved wireless network repeater |
US7391383B2 (en) * | 2002-12-16 | 2008-06-24 | Next-Rf, Inc. | Chiral polarization ultrawideband slot antenna |
US20040146013A1 (en) | 2003-01-22 | 2004-07-29 | Hong Kong Applied Science And Technology Research Institute Co., Ltd | Wireless local area network time division duplex relay system with high speed automatic up-link and down-link detection |
US7440785B2 (en) | 2003-03-07 | 2008-10-21 | Nortel Networks Limited | Method and apparatus for enhancing link range in a wireless network using self-configurable antenna |
US20040229563A1 (en) | 2003-02-14 | 2004-11-18 | Kabushiki Kaisha Toshiba | Communication network for indoor environment |
JP4624981B2 (en) | 2003-02-24 | 2011-02-02 | クゥアルコム・インコーポレイテッド | Prevent repeater oscillation |
US20040166802A1 (en) | 2003-02-26 | 2004-08-26 | Ems Technologies, Inc. | Cellular signal enhancer |
JP4529375B2 (en) | 2003-04-28 | 2010-08-25 | パナソニック電工株式会社 | Wireless relay device |
US20040218683A1 (en) | 2003-05-01 | 2004-11-04 | Texas Instruments Incorporated | Multi-mode wireless devices having reduced-mode receivers |
JP4564012B2 (en) | 2003-05-28 | 2010-10-20 | テレフオンアクチーボラゲット エル エム エリクソン(パブル) | Method and system for a wireless communication network utilizing relay |
US7397785B2 (en) | 2003-05-28 | 2008-07-08 | Nokia Corporation | Method for enhancing fairness and performance in a multihop ad hoc network and corresponding system |
US7215964B2 (en) | 2003-06-06 | 2007-05-08 | Nokia Corporation | Asymmetric radio access network, and associated method, for communicating data at high data rates |
US7352696B2 (en) * | 2003-08-08 | 2008-04-01 | Intel Corporation | Method and apparatus to select an adaptation technique in a wireless network |
JP2005072646A (en) | 2003-08-22 | 2005-03-17 | Toshiba Corp | Reception re-transmission shared antenna for gap filler |
US7676194B2 (en) * | 2003-08-22 | 2010-03-09 | Rappaport Theodore S | Broadband repeater with security for ultrawideband technologies |
KR100585726B1 (en) | 2003-09-03 | 2006-06-07 | 엘지전자 주식회사 | Method and apparatus for beam forming of array antenna in mobile terminal |
US7194275B2 (en) * | 2003-10-02 | 2007-03-20 | Telefonaktiebolaget Lm Ericsson (Publ) | Position determination of mobile stations |
JP4354245B2 (en) | 2003-10-02 | 2009-10-28 | 日本電信電話株式会社 | Wireless relay device |
EP1687929B1 (en) | 2003-11-17 | 2010-11-10 | Quellan, Inc. | Method and system for antenna interference cancellation |
JP4663653B2 (en) | 2003-11-19 | 2011-04-06 | コーニンクレッカ フィリップス エレクトロニクス エヌ ヴィ | How to access media with multi-channel devices |
US7430397B2 (en) | 2003-12-05 | 2008-09-30 | Ntt Docomo, Inc. | Radio repeater and radio relay transmission method |
CN1625066A (en) | 2003-12-05 | 2005-06-08 | 皇家飞利浦电子股份有限公司 | Two-dimensional Rick receiver for radio communication system |
JP4096875B2 (en) * | 2003-12-24 | 2008-06-04 | トヨタ自動車株式会社 | Communication device |
JP3903986B2 (en) | 2003-12-26 | 2007-04-11 | カシオ計算機株式会社 | Time information transmission / reception device and time information transmission / reception circuit |
US7299005B1 (en) | 2004-01-07 | 2007-11-20 | Sprint Spectrum L.P. | Radio frequency repeater with automated block/channel selection |
CA2553370A1 (en) | 2004-01-12 | 2005-07-28 | Behzad Barjasteh Mohebbi | Short-range cellular booster |
JP2005204116A (en) | 2004-01-16 | 2005-07-28 | Kenwood Corp | Radio communication system for business and method therefor |
JP4398752B2 (en) | 2004-02-19 | 2010-01-13 | 株式会社エヌ・ティ・ティ・ドコモ | Wireless relay system, wireless relay device, and wireless relay method |
JP4398284B2 (en) * | 2004-03-04 | 2010-01-13 | シャープ株式会社 | Base station and terminal for wireless LAN system |
JP2005295499A (en) * | 2004-03-08 | 2005-10-20 | Matsushita Electric Ind Co Ltd | Method of reducing media access overhead in radio network |
US8027642B2 (en) | 2004-04-06 | 2011-09-27 | Qualcomm Incorporated | Transmission canceller for wireless local area network |
EP1745567B1 (en) | 2004-05-13 | 2017-06-14 | QUALCOMM Incorporated | Non-frequency translating repeater with detection and media access control |
KR100610929B1 (en) | 2004-05-18 | 2006-08-10 | 삼성탈레스 주식회사 | Method for acquiring syncronization in relay of time division duplexing procedure and apparatus |
US7132988B2 (en) | 2004-05-19 | 2006-11-07 | Delphi Technologies, Inc. | Directional patch antenna |
CN1985528B (en) * | 2004-06-03 | 2010-06-09 | 高通股份有限公司 | Frequency translating repeater with low cost and high performance local oscillator architecture |
EP1605600B1 (en) | 2004-06-08 | 2014-04-23 | Freescale Semiconductors, Inc. | Wireless communication unit and method of processing a code division multiple access signal |
JP4459738B2 (en) | 2004-07-05 | 2010-04-28 | 株式会社エヌ・ティ・ティ・ドコモ | Relay device, communication device, and directivity control method |
US7623826B2 (en) | 2004-07-22 | 2009-11-24 | Frank Pergal | Wireless repeater with arbitrary programmable selectivity |
KR100590486B1 (en) | 2004-07-29 | 2006-06-19 | 에스케이 텔레콤주식회사 | Method and System for Generating Switching Timing Signal for Separating Transmitting and Receiving Signal in Optical Repeater of Mobile Telecommunication Network Using TDD and ODFM Modulation |
US7773535B2 (en) * | 2004-08-12 | 2010-08-10 | Motorola, Inc. | Method and apparatus for closed loop transmission |
US20060045193A1 (en) * | 2004-08-24 | 2006-03-02 | Nokia Corporation | System, transmitter, method, and computer program product for utilizing an adaptive preamble scheme for multi-carrier communication systems |
US7844216B2 (en) * | 2004-09-07 | 2010-11-30 | Samsung Electronics Co., Ltd. | Wireless repeater using a single RF chain for use in a TDD wireless network |
US7656842B2 (en) * | 2004-09-30 | 2010-02-02 | Motorola, Inc. | Method and apparatus for MIMO transmission optimized for successive cancellation receivers |
US7593493B2 (en) * | 2004-10-06 | 2009-09-22 | Broadcom Corporation | Method and system for pre-equalization in a single weight (SW) single channel (SC) multiple-input multiple-output (MIMO) system |
CN1805305A (en) | 2005-01-13 | 2006-07-19 | 松下电器产业株式会社 | Adaptive space-time transmit diversity method and apparatus by means of antenna selection |
JP4364129B2 (en) | 2005-01-17 | 2009-11-11 | 株式会社東芝 | Wireless relay device |
US8059727B2 (en) | 2005-01-28 | 2011-11-15 | Qualcomm Incorporated | Physical layer repeater configuration for increasing MIMO performance |
US20060203757A1 (en) | 2005-03-11 | 2006-09-14 | Spotwave Wireless Inc. | Adaptive repeater system |
US7733285B2 (en) | 2005-05-18 | 2010-06-08 | Qualcomm Incorporated | Integrated, closely spaced, high isolation, printed dipoles |
US7406060B2 (en) | 2005-07-06 | 2008-07-29 | Nortel Networks Limited | Coverage improvement in wireless systems with fixed infrastructure based relays |
WO2007062074A2 (en) | 2005-11-22 | 2007-05-31 | Qualcomm Incorporated | Directional antenna configuration for tdd repeater |
US8130629B2 (en) | 2005-11-25 | 2012-03-06 | Go Net Systems Ltd | Simultaneous simulcast and single cast hybrid multi-tone communication system |
EP2002565A4 (en) | 2006-03-31 | 2012-07-04 | Qualcomm Inc | Enhanced physical layer repeater for operation in wimax systems |
US7409186B2 (en) | 2006-07-13 | 2008-08-05 | Wilson Electronics, Inc. | Detection and elimination of oscillation within cellular network amplifiers |
US7486929B2 (en) * | 2006-07-13 | 2009-02-03 | Wilson Electronics, Inc. | Processor-controlled variable gain cellular network amplifiers with oscillation detection circuit |
US20080057862A1 (en) * | 2006-08-31 | 2008-03-06 | Smith James P | Ultra wide band stand-alone repeater/selector and systems |
JP4843088B2 (en) * | 2006-09-01 | 2011-12-21 | クゥアルコム・インコーポレイテッド | Repeater with dual receiver antenna configuration or dual transmitter antenna configuration adapted for improved isolation |
US7729669B2 (en) | 2006-09-26 | 2010-06-01 | Wilson Electronics | Processor controlled variable gain cellular network amplifier |
CA2667470A1 (en) | 2006-10-26 | 2008-05-15 | Qualcomm Incorporated | Repeater techniques for multiple input multiple output utilizing beam formers |
-
2007
- 2007-09-21 JP JP2009529255A patent/JP5199261B2/en not_active Expired - Fee Related
- 2007-09-21 US US12/307,904 patent/US8559379B2/en not_active Expired - Fee Related
- 2007-09-21 WO PCT/US2007/020485 patent/WO2008036401A2/en active Application Filing
- 2007-09-21 RU RU2009114846/08A patent/RU2444159C2/en not_active IP Right Cessation
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- 2007-09-21 CN CN200780035179.2A patent/CN101595657B/en not_active Expired - Fee Related
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CA2663419A1 (en) | 2008-03-27 |
KR101123600B1 (en) | 2012-03-21 |
RU2444159C2 (en) | 2012-02-27 |
CN101595657A (en) | 2009-12-02 |
BRPI0717490A2 (en) | 2016-10-04 |
WO2008036401A3 (en) | 2008-07-10 |
JP5199261B2 (en) | 2013-05-15 |
EP2064903A4 (en) | 2011-12-14 |
JP2010504696A (en) | 2010-02-12 |
US20090290526A1 (en) | 2009-11-26 |
WO2008036401A2 (en) | 2008-03-27 |
KR20090055041A (en) | 2009-06-01 |
CN101595657B (en) | 2014-07-09 |
RU2009114846A (en) | 2010-10-27 |
US8559379B2 (en) | 2013-10-15 |
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