WO2012064333A1

WO2012064333A1 - Providing digital data services using electrical power line(s) in optical fiber-based distributed radio frequency (rf) communications systems, and related components and methods

Info

Publication number: WO2012064333A1
Application number: PCT/US2010/056458
Authority: WO
Inventors: Wolfgang Schweiker
Original assignee: Ccs Technology, Inc.
Priority date: 2010-11-12
Filing date: 2010-11-12
Publication date: 2012-05-18

Abstract

Optical fiber-based distributed communications systems that provide and support both radio frequency (RF) communication services and digital data services are disclosed herein. The RF communication services and digital data services can be distributed over optical fiber and electrical power lines to client devices, such as remote antenna units for example. The digital data services can be distributed by using an electrical power line, where the electrical power line also provides power to remote antenna units and to digital data service components. The electrical digital data service signals that provide the digital data services are converted to electrical power signals that may be carried over the electrical power line.

Description

PROVIDING DIGITAL DATA SERVICES USING ELECTRICAL POWER LINE(S)

IN OPTICAL FIBER-BASED DISTRIBUTED RADIO FREQUENCY (RF) COMMUNICATIONS SYSTEMS, AND RELATED COMPONENTS AND METHODS

RELATED APPLICATIONS

[0001] The present application is related to U.S. Patent Application Serial No. 12/892,424, filed on September 28, 2010, entitled "Providing Digital Data Services in Optical Fiber-Based Distributed Radio Frequency (RF) Communications Systems, and Related Components and Methods," which is incorporated herein by reference in its entirety.

BACKGROUND

Field of the Disclosure

[0002] The technology of the disclosure relates to optical fiber-based distributed communications systems for distributing radio frequency (RF) signals over optical fiber.

Technical Background

[0003] Wireless communication is rapidly growing, with ever-increasing demands for high-speed mobile data communication. As an example, so-called "wireless fidelity" or "WiFi" systems and wireless local area networks (WLANs) are being deployed in many different types of areas (e.g., coffee shops, airports, libraries, etc.). Distributed communications systems communicate with wireless devices called "clients," which must reside within the wireless range or "cell coverage area" in order to communicate with an access point device.

[0004] One approach to deploying a distributed communications system involves the use of radio frequency (RF) antenna coverage areas, also referred to as "antenna coverage areas." Antenna coverage areas can have a radius in the range from a few meters up to twenty meters as an example. Combining a number of access point devices creates an array of antenna coverage areas. Because the antenna coverage areas each cover small areas, there are typically only a few users (clients) per antenna coverage area. This allows for minimizing the amount of RF bandwidth shared among the wireless system users. It may be desirable to provide antenna coverage areas in a building or other facility to provide distributed communications system access to clients within the building or facility. However, it may be desirable to employ optical fiber to distribute communication signals. Benefits of optical fiber include increased bandwidth.

[0005] One type of distributed communications system for creating antenna coverage areas, called "Radio-over-Fiber" or "RoF," utilizes RF signals sent over optical fibers. Such systems can include a head-end station optically coupled to a plurality of remote antenna units that each provides antenna coverage areas. The remote antenna units can each include RF transceivers coupled to an antenna to transmit RF signals wirelessly, wherein the remote antenna units are coupled to the head-end station via optical fiber links. The RF transceivers in the remote antenna units are transparent to the RF signals. The remote antenna units convert incoming optical RF signals from an optical fiber downlink to electrical RF signals via optical-to-electrical (O/E) converters, which are then passed to the RF transceiver. The RF transceiver converts the electrical RF signals to electromagnetic signals via antennas coupled to the RF transceiver provided in the remote antenna units. The antennas also receive electromagnetic signals (i.e., electromagnetic radiation) from clients in the antenna coverage area and convert them to electrical RF signals (i.e., electrical RF signals in wire). The remote antenna units then convert the electrical RF signals to optical RF signals via electrical-to-optical (E/O) converters. The optical RF signals are then sent over an optical fiber uplink to the headend station.

SUMMARY OF THE DETAILED DESCRIPTION

[0006] Embodiments disclosed in the detailed description include optical fiber-based distributed communications systems that provide and support both radio frequency (RF) communication services and digital data services. The RF communication services and digital data services can be distributed over optical fiber and electrical power lines to client devices, such as remote antenna units for example. The digital data services can be distributed by using an electrical power line, where the electrical power line also provides power to remote antenna units and to digital data service components. The electrical digital data service signals that provide the digital data services are converted to electrical power signals that may be carried over the electrical power line. [0007] In one embodiment, a distributed antenna system for distributing RF communications and digital data services (DDSs) to at least one remote antenna unit (RAU) is provided. The distributed antenna system includes head-end equipment. In one embodiment, the head-end equipment may comprise a head-end unit (HEU). The HEU is configured to receive at least one downlink electrical RF communications signal. The HEU is also configured to convert the at least one downlink electrical RF communications signal into at least one downlink optical RF communications signal to be communicated over at least one communications downlink to the at least one RAU. The HEU is also configured to receive at least one uplink optical RF communications signal over at least one communications uplink from the at least one RAU. The HEU is also configured to convert the at least one uplink optical RF communications signal into at least one uplink electrical RF communications signal. The distributed antenna system also includes an interconnect unit. The interconnect unit is configured to receive at least one downlink electrical digital signal containing at least one DDS, convert the at least one downlink electrical digital signal to an electrical power signal, and provide the electrical power signal over at least one electrical power line to the at least one RAU.

[0008] In another embodiment, a method of distributing RF communications and DDSs to at least one RAU in a distributed antenna system is provided. The method includes receiving at an HEU at least one downlink electrical RF communications signal. The method also includes converting the at least one downlink electrical RF communications signal into at least one downlink optical RF communications signal to be communicated over at least one communications downlink to the at least one RAU. The method also includes receiving at the HEU at least one uplink optical RF communications signal over at least one communications uplink from the at least one RAU. The method also includes converting the at least one uplink optical RF communications signal into at least one uplink electrical RF communications signal. The method also includes receiving at an interconnect unit at least one downlink electrical digital signal containing at least one DDS, converting the at least one downlink electrical digital signal into an electrical power signal, and providing the electrical power signal over an electrical power line to the at least one RAU. [0009] In another embodiment, an RAU for use in a distributed antenna system is provided. The RAU includes an optical-to-electrical (O/E) converter configured to convert received downlink optical RF communications signals to downlink electrical RF communications signals and provide the downlink electrical RF communications signals to at least one first port. The RAU also includes an electrical-to-optical (E/O) converter configured to convert uplink electrical RF communications signals received from the at least one first port into uplink optical RF communications signals. The RAU also includes a power converter coupled to at least one second port. The power converter is configured to convert electrical power signals received over an electrical power line into downlink electrical digital signals containing at least one DDS to provide to the at least one second port such that the at least one DDS may be provided.

[0010] Additional features and advantages will be set forth in the detailed description which follows, and in part will be readily apparent to those skilled in the art from that description or recognized by practicing the embodiments as described herein, including the detailed description that follows, the claims, as well as the appended drawings.

[0011] It is to be understood that both the foregoing general description and the following detailed description present embodiments, and are intended to provide an overview or framework for understanding the nature and character of the disclosure. The accompanying drawings are included to provide a further understanding, and are incorporated into and constitute a part of this specification. The drawings illustrate various embodiments, and together with the description serve to explain the principles and operation of the concepts disclosed.

BRIEF DESCRIPTION OF THE FIGURES

[0012] FIG. 1 is a schematic diagram of an exemplary optical fiber-based distributed communications system;

[0013] FIG. 2 is a more detailed schematic diagram of exemplary head-end equipment and a remote antenna unit (RAU) that can be deployed in the optical fiber- based distributed communications system of FIG. 1; [0014] FIG. 3 is a partially schematic cut-away diagram of an exemplary building infrastructure in which the optical fiber-based distributed communications system in FIG. 1 can be employed;

[0015] FIG. 4 is a schematic diagram of an exemplary embodiment of providing digital data services over downlink and uplink optical fibers separate from optical fibers providing radio frequency (RF) communication services to RAUs in an optical fiber- based distributed communications system;

[0016] FIG. 5 is a diagram of an exemplary head-end media converter (HMC) employed in the optical fiber-based distributed communications system of FIG. 4 containing digital media converters (DMCs) configured to convert electrical digital signals to optical digital signals and vice versa;

[0017] FIG. 6 is a diagram of exemplary DMCs employed in the HMC of FIG. 5;

[0018] FIG. 7 is a schematic diagram of an exemplary building infrastructure in which digital data services and RF communication services are provided in an optical fiber-based distributed communications system;

[0019] FIG. 8 is a schematic diagram of an exemplary RAU that can be employed in an optical fiber-based distributed communications system providing exemplary digital data services and RF communication services;

[0020] FIG. 9 is a schematic diagram of an exemplary embodiment of providing digital data services over an electrical power line to RAUs in an optical fiber-based distributed communications system; and

[0021] FIG. 10 is a schematic diagram of an exemplary interconnect unit (ICU) for converting a received electrical data services signal into an electrical power signal and an exemplary RAU for converting a received electrical power signal back into an electrical data services signal.

DETAILED DESCRIPTION

[0022] Reference will now be made in detail to the embodiments, examples of which are illustrated in the accompanying drawings, in which some, but not all embodiments are shown. Indeed, the concepts may be embodied in many different forms and should not be construed as limiting herein; rather, these embodiments are provided so that this disclosure will satisfy applicable legal requirements. Whenever possible, like reference numbers will be used to refer to like components or parts.

[0023] Embodiments disclosed in the detailed description include optical fiber-based distributed communications systems that provide and support both radio frequency (RF) communication services and digital data services. The RF communication services and digital data services can be distributed over optical fiber and electrical power lines to client devices, such as remote antenna units for example. The digital data services can be distributed by using an electrical power line, where the electrical power line also provides power to remote antenna units and to digital data service components. The electrical digital data service signals that provide the digital data services are converted to electrical power signals that may be carried over the electrical power line. For example, non- limiting examples of digital data services include Ethernet, Wireless Local Area Networks (WLAN), Worldwide Interoperability for Microwave Access (WiMax), Wireless Fidelity (WiFi), Digital Subscriber Line (DSL), and Long Term Evolution (LTE), etc.

[0024] Digital data services can be distributed over an electrical power line in one embodiment. The electrical power line may be separate from the optical fiber distributing RF communication services in an exemplary embodiment. Alternatively, digital data services can be distributed over an electrical power line in an optical fiber that also carries RF communication services. The electrical power line may be the same electrical power line that provides power to remote antenna units. The electrical power line may also provide power to digital data service components.

[0025] In this regard, an exemplary optical fiber-based distributed communications system that provides RF communication services without providing digital data services is described with regard to FIGS. 1-3. Various embodiments of additionally providing digital data services in conjunction with RF communication services in optical fiber- based distributed communications systems starts at FIG. 4.

[0026] In this regard, FIG. 1 is a schematic diagram of an embodiment of an optical fiber-based distributed communications system. In this embodiment, the system is an optical fiber-based distributed communications system 10 that is configured to create one or more antenna coverage areas for establishing communications with wireless client devices located in the RF range of the antenna coverage areas. The optical fiber-based distributed communications system 10 provides RF communications services (e.g., cellular services). In this embodiment, the optical fiber-based distributed communications system 10 includes head-end equipment in the form of a head-end unit (HEU) 12, one or more remote antenna units (RAUs) 14, and an optical fiber 16 that optically couples the HEU 12 to the RAU 14. The HEU 12 is configured to receive communications over downlink electrical RF signals 18D from a source or sources, such as a network or carrier as examples, and provide such communications to the RAU 14. The HEU 12 is also configured to return communications received from the RAU 14, via uplink electrical RF signals 18U, back to the source or sources. In this regard, in this embodiment, the optical fiber 16 includes at least one downlink optical fiber 16D to carry signals communicated from the HEU 12 to the RAU 14 and at least one uplink optical fiber 16U to carry signals communicated from the RAU 14 back to the HEU 12.

[0027] The optical fiber-based distributed communications system 10 has an antenna coverage area 20 that can be substantially centered about the RAU 14. The antenna coverage area 20 of the RAU 14 forms an RF coverage area 21. The HEU 12 is adapted to perform or to facilitate any one of a number of Radio-over-Fiber (RoF) applications, such as radio frequency identification (RFID), WLAN communication, or cellular phone service. Shown within the antenna coverage area 20 is a client device 24 in the form of a mobile device as an example, which may be a cellular telephone as an example. The client device 24 can be any device that is capable of receiving RF communication signals. The client device 24 includes an antenna 26 (e.g., a wireless card) adapted to receive and/or send electromagnetic RF signals.

[0028] With continuing reference to FIG. 1, to communicate the electrical RF signals over the downlink optical fiber 16D to the RAU 14, to in turn be communicated to the client device 24 in the antenna coverage area 20 formed by the RAU 14, the HEU 12 includes an electrical-to-optical (E/O) converter 28. The E/O converter 28 converts the downlink electrical RF signals 18D to downlink optical RF signals 22D to be communicated over the downlink optical fiber 16D. The RAU 14 includes an optical-to- electrical (O/E) converter 30 to convert received downlink optical RF signals 22D back to electrical RF signals to be communicated wirelessly through an antenna 32 of the RAU 14 to client devices 24 located in the antenna coverage area 20.

[0029] Similarly, the antenna 32 is also configured to receive wireless RF communications from client devices 24 in the antenna coverage area 20. In this regard, the antenna 32 receives wireless RF communications from client devices 24 and communicates electrical RF signals representing the wireless RF communications to an E/O converter 34 in the RAU 14. The E/O converter 34 converts the electrical RF signals into uplink optical RF signals 22U to be communicated over the uplink optical fiber 16U. An O/E converter 36 provided in the HEU 12 converts the uplink optical RF signals 22U into uplink electrical RF signals, which can then be communicated as uplink electrical RF signals 18U back to a network or other source. The HEU 12 in this embodiment is not able to distinguish the location of the client devices 24 in this embodiment. The client device 24 could be in the range of any antenna coverage area 20 formed by an RAU 14.

[0030] FIG. 2 is a more detailed schematic diagram of the exemplary optical fiber- based distributed communications system 10 of FIG. 1 that provides electrical RF service signals for a particular RF service or application. In an exemplary embodiment, the HEU 12 includes a service unit 37 that provides electrical RF service signals by passing (or conditioning and then passing) such signals from one or more outside networks 38 via a network link 39. In a particular example embodiment, this includes providing WLA signal distribution as specified in the Institute of Electrical and Electronics Engineers (IEEE) 802.11 standard, i.e., in the frequency range from 2.4 to 2.5 GigaHertz (GHz) and from 5.0 to 6.0 GHz. Any other electrical RF signal frequencies are possible. In another exemplary embodiment, the service unit 37 provides electrical RF service signals by generating the signals directly. In another exemplary embodiment, the service unit 37 coordinates the delivery of the electrical RF service signals between client devices 24 within the antenna coverage area 20.

[0031] With continuing reference to FIG. 2, the service unit 37 is electrically coupled to the E/O converter 28 that receives the downlink electrical RF signals 18D from the service unit 37 and converts them to corresponding downlink optical RF signals 22D. In an exemplary embodiment, the E/O converter 28 includes a laser suitable for delivering sufficient dynamic range for the RoF applications described herein, and optionally includes a laser driver/amplifier electrically coupled to the laser. Examples of suitable lasers for the E/O converter 28 include, but are not limited to, laser diodes, distributed feedback (DFB) lasers, Fabry-Perot (FP) lasers, and vertical cavity surface emitting lasers (VCSELs).

[0032] With continuing reference to FIG. 2, the HEU 12 also includes the O/E converter 36, which is electrically coupled to the service unit 37. The O/E converter 36 receives the uplink optical RF signals 22U and converts them to corresponding uplink electrical RF signals 18U. In an example embodiment, the O/E converter 36 is a photodetector, or a photodetector electrically coupled to a linear amplifier. The E/O converter 28 and the O/E converter 36 constitute a "converter pair" 35, as illustrated in FIG. 2.

[0033] In accordance with an exemplary embodiment, the service unit 37 in the HEU 12 can include an RF signal conditioner unit 40 for conditioning the downlink electrical RF signals 18D and the uplink electrical RF signals 18U, respectively. The service unit 37 can include a digital signal processing unit ("digital signal processor") 42 for providing to the RF signal conditioner unit 40 an electrical signal that is modulated onto an RF carrier to generate a desired downlink electrical RF signal 18D. The digital signal processor 42 is also configured to process a demodulation signal provided by the demodulation of the uplink electrical RF signal 18U by the RF signal conditioner unit 40. The HEU 12 can also include an optional central processing unit (CPU) 44 for processing data and otherwise performing logic and computing operations, and a memory unit 46 for storing data, such as data to be transmitted over a WLA or other network for example.

[0034] With continuing reference to FIG. 2, the RAU 14 also includes a converter pair 48 comprising the O/E converter 30 and the E/O converter 34. The O/E converter 30 converts the received downlink optical RF signals 22D from the HEU 12 back into downlink electrical RF signals 50D. The E/O converter 34 converts uplink electrical RF signals 50U received from the client device 24 into the uplink optical RF signals 22U to be communicated to the HEU 12. The O/E converter 30 and the E/O converter 34 are electrically coupled to the antenna 32 via an RF signal-directing element 52, such as a circulator for example. The RF signal-directing element 52 serves to direct the downlink electrical RF signals 50D and the uplink electrical RF signals 50U, as discussed below. In accordance with an exemplary embodiment, the antenna 32 can include any type of antenna, including but not limited to one or more patch antennas, such as disclosed in U.S. Patent Application Serial. No. 1 1/504,999, filed August 16, 2006 entitled "Radio- over-Fiber Transponder With A Dual-Band Patch Antenna System," and U.S. Patent Application Serial No. 11/451 ,553, filed June 12, 2006 entitled "Centralized Optical Fiber-Based Wireless Picocellular Systems and Methods," both of which are incorporated herein by reference in their entireties.

[0035] With continuing reference to FIG. 2, the optical fiber-based distributed communications system 10 also includes a power supply 54 that provides an electrical power signal 56. The power supply 54 is electrically coupled to the HEU 12 for powering the power-consuming elements therein. In an exemplary embodiment, an electrical power line 58 runs through the HEU 12 and over to the RAU 14 to power the O/E converter 30 and the E/O converter 34 in the converter pair 48, the optional RF signal-directing element 52 (unless the RF signal-directing element 52 is a passive device such as a circulator for example), and any other power-consuming elements provided. In an exemplary embodiment, the electrical power line 58 includes two wires 60 and 62 that carry a single voltage and that are electrically coupled to a DC power converter 64 at the RAU 14. The DC power converter 64 is electrically coupled to the O/E converter 30 and the E/O converter 34 in the converter pair 48, and changes the voltage or levels of the electrical power signal 56 to the power level(s) required by the power-consuming components in the RAU 14. In an exemplary embodiment, the DC power converter 64 is either a DC/DC power converter or an AC/DC power converter, depending on the type of electrical power signal 56 carried by the electrical power line 58. In another example embodiment, the electrical power line 58 (dashed line) runs directly from the power supply 54 to the RAU 14 rather than from or through the HEU 12. In another example embodiment, the electrical power line 58 includes more than two wires and may carry multiple voltages.

[0036] In an exemplary embodiment, the electrical power line 58 may also be used to carry a digital data signal in order to provide digital data services (DDSs), as discussed more fully below with respect to FIGS. 8-10. [0037] To provide further exemplary illustration of how an optical fiber-based distributed communications system can be deployed indoors, FIG. 3 is provided. FIG. 3 is a partially schematic cut-away diagram of a building infrastructure 70 employing an optical fiber-based distributed communications system. The system may be the optical fiber-based distributed communications system 10 of FIGS. 1 and 2. The building infrastructure 70 generally represents any type of building in which the optical fiber- based distributed communications system 10 can be deployed. As previously discussed with regard to FIGS. 1 and 2, the optical fiber-based distributed communications system 10 incorporates the HEU 12 to provide various types of communication services to coverage areas within the building infrastructure 70, as an example. For example, as discussed in more detail below, the optical fiber-based distributed communications system 10 in this embodiment is configured to receive wireless RF signals and convert the RF signals into RoF signals to be communicated over the optical fiber 16 to multiple RAUs 14. The optical fiber-based distributed communications system 10 in this embodiment can be, for example, an indoor distributed antenna system (IDAS) to provide wireless service inside the building infrastructure 70. These wireless signals can include cellular services, wireless services such as RFID tracking, Wireless Fidelity (WiFi), local area network (LAN), WLAN, and combinations thereof, as examples.

[0038] With continuing reference to FIG. 3, the building infrastructure 70 in this embodiment includes a first (ground) floor 72, a second floor 74, and a third floor 76. The floors 72, 74, 76 are serviced by the HEU 12 through a main distribution frame 78 to provide antenna coverage areas 80 in the building infrastructure 70. Only the ceilings of the floors 72, 74, 76 are shown in FIG. 3 for simplicity of illustration. In the example embodiment, a main cable 82 has a number of different sections that facilitate the placement of a large number of RAUs 14 in the building infrastructure 70. Each RAU 14 in turn services its own coverage area in the antenna coverage areas 80. The main cable 82 can include, for example, a riser cable 84 that carries all of the downlink and uplink optical fibers 16D, 16U to and from the HEU 12. The riser cable 84 may be routed through an interconnect unit (ICU) 85. The ICU 85 may be provided as part of or separate from the power supply 54 in FIG. 2. The ICU 85 may also be configured to provide power to the RAUs 14 via the electrical power line 58, as illustrated in FIG. 2 and discussed above, provided inside an array cable 87, or tail cable or home -run tether cable as other examples, and distributed with the downlink and uplink optical fibers 16D, 16U to the RAUs 14. The main cable 82 can include one or more multi-cable (MC) connectors adapted to connect select downlink and uplink optical fibers 16D, 16U, along with an electrical power line (e, g. electrical power line 58 in FIG. 2), to a number of optical fiber cables 86.

[0039] The main cable 82 enables multiple optical fiber cables 86 to be distributed throughout the building infrastructure 70 (e.g., fixed to the ceilings or other support surfaces of each floor 72, 74, 76) to provide the antenna coverage areas 80 for the first, second and third floors 72, 74 and 76. In an example embodiment, the HEU 12 is located within the building infrastructure 70 (e.g., in a closet or control room), while in another example embodiment the HEU 12 may be located outside of the building infrastructure 70 at a remote location. A base transceiver station (BTS) 88, which may be provided by a second party such as a cellular service provider, is connected to the HEU 12, and can be co-located or located remotely from the HEU 12. A BTS is any station or source that provides an input signal to the HEU 12 and can receive a return signal from the HEU 12. In a typical cellular system, for example, a plurality of BTSs are deployed at a plurality of remote locations to provide wireless telephone coverage. Each BTS serves a corresponding cell and when a mobile client device enters the cell, the BTS communicates with the mobile client device. Each BTS can include at least one radio transceiver for enabling communication with one or more subscriber units operating within the associated cell. As another example, wireless repeaters or bi-directional amplifiers could also be used to serve a corresponding cell in lieu of a BTS. Alternatively, radio input could be provided by a repeater or picocell as other examples.

[0040] The optical fiber-based distributed communications system 10 in FIGS. 1-3 and described above provides point-to-point communications between the HEU 12 and the RAU 14. Each RAU 14 communicates with the HEU 12 over a distinct downlink and uplink optical fiber pair to provide the point-to-point communications. Whenever an RAU 14 is installed in the optical fiber-based distributed communications system 10, the RAU 14 is connected to a distinct downlink and uplink optical fiber pair connected to the HEU 12. The downlink and uplink optical fibers 16D, 16U may be provided in a fiber optic cable. Multiple downlink and uplink optical fiber pairs can be provided in a fiber optic cable to service multiple RAUs 14 from a common fiber optic cable. For example, with reference to FIG. 3, RAUs 14 installed on a given floor 72, 74, or 76 may be serviced from the same optical fiber 16. In this regard, the optical fiber 16 may have multiple nodes where distinct downlink and uplink optical fiber pairs can be connected to a given RAU 14. One downlink optical fiber 16 could be provided to support multiple channels each using wavelength-division multiplexing (WDM), as discussed in U.S. Patent Application Serial No. 12/892,424 entitled "Providing Digital Data Services in Optical Fiber-Based Distributed Radio Frequency (RF) Communications Systems, and Related Components and Methods," incorporated herein by reference in its entirety. Other options for WDM and frequency-division multiplexing (FDM) are also disclosed in U.S. Patent Application Serial No. 12/892,424, any of which can be employed in any of the embodiments disclosed herein.

[0041] The HEU 12 may be configured to support any frequencies desired, including but not limited to US FCC and Industry Canada frequencies (824-849 MHz on uplink and 869-894 MHz on downlink), US FCC and Industry Canada frequencies (1850-1915 MHz on uplink and 1930-1995 MHz on downlink), US FCC and Industry Canada frequencies (1710-1755 MHz on uplink and 2110-2155 MHz on downlink), US FCC frequencies (698-716 MHz and 776-787 MHz on uplink and 728-746 MHz on downlink), EU R & TTE frequencies (880-915 MHz on uplink and 925-960 MHz on downlink), EU R & TTE frequencies (1710-1785 MHz on uplink and 1805-1880 MHz on downlink), EU R & TTE frequencies (1920-1980 MHz on uplink and 2110-2170 MHz on downlink), US FCC frequencies (806-824 MHz on uplink and 851-869 MHz on downlink), US FCC frequencies (896-901 MHz on uplink and 929-941 MHz on downlink), US FCC frequencies (793-805 MHz on uplink and 763-775 MHz on downlink), and US FCC frequencies (2495-2690 MHz on uplink and downlink).

[0042] It may be desirable to provide both digital data services and RF communication services for client devices. For example, it may be desirable to provide digital data services and RF communication services in the building infrastructure 70 to client devices located therein. Wired and wireless devices may be located in the building infrastructure 70 that are configured to access digital data services. Examples of digital data services include, but are not limited to, Ethernet, WLAN, WiMax, WiFi, DSL, and LTE, etc. Ethernet standards could be supported, including but not limited to 100 Megabits per second (Mbs) (i.e., fast Ethernet) or Gigabit (Gb) Ethernet, or ten Gigabit (10G) Ethernet. Example of digital data devices include, but are not limited to, wired and wireless servers, wireless access points (WAPs), gateways, desktop computers, hubs, switches, remote radio heads (RRHs), baseband units (BBUs), and femtocells. A separate digital data services network can be provided to provide digital data services to digital data devices.

[0043] In this regard, embodiments disclosed herein provide optical fiber-based distributed communications systems that support both RF communication services and digital data services. The RF communication services and digital data services can be distributed over optical fiber to client devices, such as remote antenna units for example. In one embodiment, digital data services can be distributed over an electrical power line. In an exemplary embodiment, the electrical power line may be in an optical fiber separate from the fiber optic cables distributing RF communication services. Alternatively, digital data services can be distributed over an electrical power line in a common fiber optic cables with RF communication services in an optical fiber-based distributed communications system.

[0044] To provide digital data services in an optical fiber-based distributed communications system, electrical digital data services signals may either be converted into optical digital signals and carried over optical fibers, or the electrical digital data services signals may be converted to electrical power signals that may be carried over an electrical power line. An exemplary embodiment of converting the electrical digital data services signals into optical digital signals is discussed herein with respect to FIG. 4. An exemplary embodiment of converting the electrical digital data services signals into electrical power signals is discussed below with respect to FIGS. 8-10.

[0045] FIG. 4 is a schematic diagram of an exemplary embodiment of providing digital data services over separate downlink and uplink optical fibers from RF communication services to RAUs in an optical fiber-based distributed communications system 90. The optical fiber-based distributed communications system 90 includes some optical communication components provided in the optical fiber-based distributed communications system 10 of FIGS. 1-3. These common components are illustrated in FIG. 4 with common element numbers with FIGS. 1-3. As illustrated in FIG. 4, the HEU 12 is provided. The HEU 12 receives the downlink electrical RF signals 18D from the BTS 88. As previously discussed, the HEU 12 converts the downlink electrical RF signals 18D to downlink optical RF signals 22D to be distributed to the RAUs 14. The HEU 12 is also configured to convert the uplink optical RF signals 22U received from the RAUs 14 into uplink electrical RF signals 18U to be provided to the BTS 88 and onto a network 93 connected to the BTS 88. A patch panel 92 may be provided to receive the downlink and uplink optical fibers 16D, 16U configured to carry the downlink and uplink optical RF signals 22D, 22U. The downlink and uplink optical fibers 16D, 16U may be bundled together in one or more riser cables 84 and provided to one or more ICUs 85, as previously discussed and illustrated in FIG. 3.

[0046] To provide digital data services in the optical fiber-based distributed communications system 90 in the embodiment of FIG. 4, a digital data service controller (also referred to as "DDS controller") in the form of a head-end media converter (HMC) 94 in this example is provided. The DDS controller can include only a media converter for provision media conversion functionality or can include additional functionality to facilitate digital data services. A DDS controller is a controller configured to provide digital data services over a communications link, interface, or other communications channel or line, which may be either wired, wireless, or a combination of both.

[0047] FIG. 5 illustrates an example of the HMC 94. The HMC 94 includes a housing 95 configured to house digital media converters (DMCs) 97 to interface to a digital data services switch 96 (FIG. 4) to support and provide digital data services. For example, the digital data services switch 96 could be an Ethernet switch. The digital data services switch 96 may be configured to provide Gigabit (Gb) Ethernet digital data service as an example. The DMCs 97 are configured to convert electrical digital signals to optical digital signals, and vice versa. The DMCs 97 may be configured for plug and play installation (i.e., installation and operability without user configuration required) into the HMC 94. FIG. 6 illustrates an exemplary DMC 97 that can be disposed in the housing 95 of the HMC 94. For example, the DMC 97 may include Ethernet input connectors or adapters (e.g., RJ-45) and optical fiber output connectors or adapters (e.g., LC, SC, ST, MTP).

[0048] With reference to FIG. 4, the HMC 94 (via the DMCs 97) in this embodiment is configured to convert downlink electrical digital signals (or downlink electrical digital data services signals) 98D over digital line cables 99 from the digital data services switch 96 into downlink optical digital signals (or downlink optical digital data services signals) 100D that can be communicated over downlink optical fiber 102D to RAUs 14. The HMC 94 (via the DMCs 97) is also configured to receive uplink optical digital signals 100U from the RAUs 14 via uplink optical fiber 102U and convert the uplink optical digital signals 100U into uplink electrical digital signals 98U to be communicated to the digital data services switch 96. In this manner, the digital data services can be provided over optical fiber as part of the optical fiber-based distributed communications system 90 to provide digital data services in addition to RF communication services. Client devices located at the RAUs 94 can access these digital data services and/or RF communication services depending on their configuration. For example, FIG. 7 illustrates the building infrastructure 70 of FIG. 3, but with illustrative examples of digital data services and digital client devices that can be provided to client devices in addition to RF communication services in the optical fiber-based distributed communications system 90. As illustrated in FIG. 7, exemplary digital data services include WLA 106, femtocells 108, gateways 110, baseband units (BBU) 112, remote radio heads (RRH) 114, and servers 116.

[0049] With reference back to FIG. 4, in this embodiment, the downlink and uplink optical fibers 102D, 102U are provided in a fiber optic cable 104 that is interfaced to the ICU 85. The ICU 85 provides a common point in which the downlink and uplink optical fibers 102D, 102U carrying digital optical signals can be bundled with the downlink and uplink optical fibers 16U, 16D carrying RF optical signals. One or more of the fiber optic cables 104, also referenced herein as array cables 104, can be provided containing the downlink and uplink optical fibers 16D, 16U for RF communication services and downlink and uplink optical fibers 102D, 102U for digital data services to be routed and provided to the RAUs 14. Any combination of services or types of optical fibers can be provided in the array cable 104. For example, the array cable 104 may include single mode and/or multi-mode optical fibers for RF communication services and/or digital data services.

[0050] Examples of ICUs that may be provided in the optical fiber-based distributed communications system 90 to distribute both downlink and uplink optical fibers 16D, 16U for RF communication services and downlink and uplink optical fibers 102D, 102U for digital data services are described in U.S. Patent Application Serial No. 12/466,514, filed on May 15, 2009 and entitled "Power Distribution Devices, Systems, and Methods For Radio-Over-Fiber (RoF) Distributed Communication," incorporated herein by reference in its entirety, and U.S. Provisional Patent Application Serial No. 61/330,385, filed on May 2, 2010 and entitled "Power Distribution in Optical Fiber-based Distributed Communication Systems Providing Digital Data and Radio-Frequency (RF) Communication Services, and Related Components and Methods," both of which are incorporated herein by reference in their entireties.

[0051] Other configurations are possible to provide digital data services in an optical fiber-based distributed communications system. In one embodiment, instead of the HMC 94 being provided separate from the HEU 12, the HMC 94 may be co-located with the HEU 12. The downlink and uplink optical fibers 102D, 102U for providing digital data services from the digital data services switch 96 may be connected to the patch panel 92. The downlink and uplink optical fibers 16D, 16U for RF communications and the downlink and uplink optical fibers 102D, 102U for digital data services may be routed to the ICU 85, similar to FIG. 2.

[0052] In another embodiment, the downlink and uplink optical fibers 16D, 16U for RF communications, and the downlink and uplink optical fibers 102D, 102U for digital data services, may be provided in a common fiber optic cable or provided in separate fiber optic cables. Further, standalone media converters may be provided separately from the RAUs 14 in lieu of being integrated with RAUs 14, as illustrated in FIG. 4.

[0053] With continuing reference to FIG. 4, some RAUs 14 can be connected to access units (AUs) 118, which may be access points or other devices supporting digital data services. The AUs 118 can also be connected directly to the HEU 12. AUs 118 are illustrated, but the AUs 118 could be any other device supporting digital data services. In the example of AUs, the AUs 118 provide access to the digital data services provided by the digital data services switch 96. This is because the downlink and uplink optical fibers 102D, 102U carrying downlink and uplink optical digital signals 100D, 100U converted from downlink and uplink electrical digital signals 98D, 98U from the digital data services switch 96 are provided to the AUs 118 via the array cables 104 and RAUs 14. Digital data client devices can access the AUs 118 to access digital data services provided through the digital data services switch 96. The AUs 118 may also each include antennas 152 to provide wireless digital data services in lieu of or in addition to wired services through a port 128 (FIG. 8) through the RAUs 14.

[0054] An exemplary embodiment of converting the electrical digital data services signals into electrical power signals is discussed below with respect to FIGS. 8-10. This embodiment uses the electrical power line that is already present in many optical fiber- based distributed systems for providing power to the RAUs, thereby offering a simple and cost effective solution. In particular, this embodiment does not require a separate pair of optical fibers for distributing both the RF and digital data signals, nor does it require wave division multiplexing (WDM) or frequency division multiplexing (FDM) that may be required if the RF and digital data signals are to be carried over the same optical fiber.

[0055] Digital data service clients, such as AUs, require power to operate and to receive digital data services. By providing digital data services as part of an optical fiber- based distributed communications system, power distributed to the RAUs in the optical fiber-based distributed communications system can also be used to provide access to power for digital data service clients. This may be a convenient method of providing power to digital data service clients as opposed to providing separate power sources for digital data service clients. For example, power distributed to the RAUs 14 in FIG. 4 by or through the ICU 85 can also be used to provide power to the AUs 118 located at RAUs 14 in the optical fiber-based distributed communications system 90. In this regard, the ICUs 85 may be configured to provide power for both RAUs 14 and the AUs 118. A power supply may be located within the ICU 85, but could also be located outside of the ICU 85 and provided over an electrical power line 120, as illustrated in FIG. 4. The ICU 85 may receive either alternating current (AC) or direct current (DC) power. The ICU 85 may receive 110 Volts (V) to 240V AC or DC power. The ICU 85 can be configured to produce any voltage and power level desired. The power level is based on the number of RAUs 14 and the expected loads to be supported by the RAUs 14 and any digital devices connected to the RAUs 14 in FIG. 4. It may further be desired to provide additional power management features in the ICU 85. For example, one or more voltage protection circuits may be provided.

[0056] FIG. 8 is a schematic diagram of exemplary internal components in the RAU 14 of FIG. 4 to further illustrate how the downlink and uplink optical fibers 16D, 16U, the downlink and uplink optical fibers 102D, 102U, and electrical power are provided to the RAU 14 and can be distributed therein. In an exemplary embodiment, the downlink and uplink optical fibers 16D, 16U are used for RF communications and the downlink and uplink optical fibers 102D, 102U are used for digital data services, as discussed above with respect to FIG. 4. In another exemplary embodiment, the electrical power line 58 may be used to provide the digital data services to the RAU 14.

[0057] As illustrated in FIG. 8, the array cable 104 contains the downlink and uplink optical fibers 16D, 16U, the downlink and uplink optical fibers 102D, 102U, and the electrical power line 58 (see also, FIG. 2) carrying power from the ICU 85. As previously discussed with regard to FIG. 2, the electrical power line 58 may comprise two wires 60, 62, which may be copper lines for example.

[0058] The downlink and uplink optical fibers 16D, 16U, the downlink and uplink optical fibers 102D, 102U, and the electrical power line 58 come into a housing 124 of the RAU 14. The downlink and uplink optical fibers 16D, 16U are routed to the O/E converter 30 and E/O converter 34, respectively, and to the antenna 32, as also illustrated in FIG. 2 and previously discussed. The downlink and uplink optical fibers 102D, 102U capable of providing digital data services in one embodiment are routed to a digital data services interface 126 provided as part of the RAU 14 to provide access to digital data services via the port 128, which will be described in more detail below. The electrical power line 58 carries power that is configured to provide power to the O/E converter 30 and E/O converter 34 and to the digital data services interface 126. In this regard, the electrical power line 58 is coupled to a voltage controller 130 that regulates and provides the correct voltage to the O/E converter 30 and E/O converter 34 and to the digital data services interface 126 and other circuitry in the RAU 14. In an exemplary embodiment, the electrical power line 58 may also carry the signals for the digital data services.

[0059] In the embodiment where the downlink and uplink optical fibers 102D, 102U provide the digital data services, the digital data services interface 126 is configured to convert downlink optical digital signals 100D on the downlink optical fiber 102D into downlink electrical digital signals 132D that can be accessed via the port 128. The digital data services interface 126 is also configured to convert uplink electrical digital signals 132U received through the port 128 into uplink optical digital signals 100U to be provided back to the HMC 94 (see FIG. 4). In this regard, a media converter 134 is provided in the digital data services interface 126 to provide these conversions. The media converter 134 contains an O/E digital converter 136 to convert downlink optical digital signals 100D on the downlink optical fiber 102D into downlink electrical digital signals 132D. The media converter 134 also contains an E/O digital converter 138 to convert uplink electrical digital signals 132U received through the port 128 into uplink optical digital signals 100U to be provided back to the HMC 94. In this regard, power from the electrical power line 58 is provided to the digital data services interface 126 to provide power to the O/E digital converter 136 and the E/O digital converter 138.

[0060] According to one embodiment, the electrical digital data services signals may be provided to the RAU 14 without converting the electrical digital data services signals to optical digital data services signals. In this embodiment, no media converter 134 with an O/E digital converter 136 and E/O digital converter 138 is required. Instead, the electrical digital data services signals can be converted to electrical power signals and then transmitted over the electrical power line 58. The conversion of the electrical digital data services signals are converted to electrical power signals may be done by converters in the ICU 85 and in the RAU 14 in one embodiment, as described more fully below. The electrical power line 58 is configured to carry both downlink and uplink electrical power signals which have been converted from downlink and uplink electrical digital data services signals in one embodiment. Alternatively, if the electrical digital data service signals are converted to optical digital data service signals, an O-E converter could be employed in the ICU 85 to convert the optical digital data service signals to electrical digital data service signal and then convert a portion into electrical power signals.In this embodiment, where the electrical power line 58 provides the digital data services to the RAU 14, the downlink electrical data services signals 98D (see FIG. 4) are converted into downlink electrical power signals 122D and transmitted along the electrical power line 58 toward the RAU 14, as described more fully with respect to FIG. 9 below. In one embodiment, the ICU 85 will perform this conversion. After the converted downlink electrical power signals 122D have been transmitted along the electrical power line 58 and received at the RAU 14, the digital data services interface 126 at the RAU 14 is configured to convert the downlink electrical power signals 122D received on the electrical power line 58 into downlink electrical digital signals 132D that can be accessed via the port 128. The digital data services interface 126 is also configured to convert uplink electrical digital signals 132U received through the port 128 into uplink electrical power signals 122U to be provided back to the ICU 85 (see FIG. 9).

[0061] In this regard, a converter is provided in the digital data services interface 126 or elsewhere in the RAU 14 to provide these conversions (see FIG. 9). The converter is configured to convert downlink electrical power signals 122D received from the electrical power line 58 into downlink electrical digital signals 132D. The converter is also configured to convert uplink electrical digital signals 132U received through the port 128 into uplink electrical power signals 122U to be provided back to the ICU 85. In this regard, the electrical power line 58 provides digital data services to the RAU 14, while also providing power to the digital data services interface 126 to provide power to the O/E digital converter 136 and E/O digital converter 138.

[0062] Because electrical power is provided to the RAU 14 and the digital data services interface 126, this also provides an opportunity to provide power for digital devices connected to the RAU 14 via the port 128. In this regard, a power interface 140 is also provided in the digital data services interface 126, as illustrated in FIG. 8. The power interface 140 is configured to receive power from the electrical power line 58 via the voltage controller 130 and also to make power accessible through the port 128. In this manner, if a client device contains a compatible connector to connect to the port 128, not only will digital data services be accessible, but power from the electrical power line 58 can also be accessed through the same port 128. Alternatively, the power interface 140 could be coupled to a separate port from the port 128 for digital data services. [0063] If there is not enough power for the digital devices connected to the RAU 14, power may be allocated according to a control scheme, as described in U.S. Provisional Application Serial No. 61/392,660, filed October 13, 2010, entitled "Local Power Management For Remote Antenna Units in Distributed Antenna Systems," and U.S. Provisional Application Serial No. 61/392,687, filed October 13, 2010, entitled "Power Management For Remote Antenna Units in Distributed Antenna Systems," which are both incorporating herein by references in their entireties..

[0064] For example, if the digital data services are provided over Ethernet, the power interface 140 could be provided as a Power-over-Ethernet (PoE) interface. The port 128 could be configured to receive a RJ-45 Ethernet connector compatible with PoE as an example. In this manner, an Ethernet connector connected into the port 128 would be able to access both Ethernet digital data services to and from the downlink and uplink optical fibers 102D, 102U to the HMC 94 as well as access power distributed by the ICU 85 over the array cable 104 provided by the electrical power line 58.

[0065] Further, the HEU 12 could include low level control and management of the media converter 134 using communication supported by the HEU 12. For example, the media converter 134 could report functionality data (e.g., power on, reception of optical digital data, etc.) to the HEU 12 over the uplink optical fiber 16U that carries communication services. The RAU 14 can include a microprocessor that communicates with the media converter 134 to receive this data and communicate this data over the uplink optical fiber 16U to the HEU 12.

[0066] FIG. 9 is a schematic diagram of an exemplary embodiment of providing digital data services over an electrical power line to RAUs in an optical fiber-based distributed communications system. A cable 101 carries downlink and uplink electrical data services signals 98D, 98U between the digital data services switch 96 and the ICU 85. In one embodiment, the digital data services switch 96 is an Ethernet switch and the cable 101 is a copper cable, e.g. Cat 5, suitable for carrying the Ethernet signal from the digital data services switch 96 to the ICU 85. In one embodiment, the digital data services switch 96 may be remote from the ICU 85. In other embodiments, the digital data services switch 86 may be near or co-located with the ICU 85. [0067] For electrical digital services signal transmissions, the ICU 85 conditions the downlink and uplink electrical data services signals 98D, 98U such that a high quality transmission over a simple copper pair, such as that found in a typical power line (e,g. electrical power line 58), is possible. The ICU 85 may include a converter module 203 configured to convert the downlink and uplink electrical data services signals 98D, 98U into electrical power signals 122D, 122U. In one embodiment, the converter module 203 is an Ethernet over Powerline (EoP) converter. The converter module 203 is located at the ICU 85 where the electrical power is launched into the array cable 104, which contains the electrical power line 58 and one or more optical fibers. The digital data services switch 96 is connected via the cable 101 to the ICU 85. The downlink and uplink electrical data services signals 98D, 98U are converted into downlink and uplink electrical power signals 122D, 122U. In one embodiment, the downlink and uplink electrical power signals 122D, 122U are Ethernet signals, such as 100BASE-T. The downlink and uplink electrical power signals 122D, 122U are then transmitted over the electrical power line 58. In one embodiment, the electrical power line 58 has a pair of copper wires 60, 62, as seen in FIG. 2, that carries a single voltage. The electrical power line 58 may carry both uplink and downlink electric power signals in addition to DC power.

[0068] There are known methods of converting the downlink and uplink electrical data services signals 98D, 98U into downlink and uplink electrical power signals 122D, 122U such that they may be transmitted over the electrical power line 58. One such known technology is Powerline Communication (PLC). In one embodiment, the conversion and transmission of the electrical data services signals 98D, 98U could be done per the HomePlug AV standard, or ITU-T G.hn standard. HomePlug AV equipment is capable of transmitting data at 200 megabits per second (Mbps) over 300 meters (m) of regular power conductors. One example of the HomePlug AV equipment is the INT6400/INT 1400 HomePlug AV Chip Set from Atheros, 540 Great America Pkwy, Santa Clara, CA 95054. Another example is the Actiontec HPE200AVP (see, e.g. http://www.actiontec.coriv^fpiOducts/datasheets/ActiontecHPE200AVPncsdatasheet.pdf ).

[0069] Any of the RAUs 14 in FIG. 9 may contain a separate converter 204 for performing the corresponding conversion of the downlink and uplink electrical power signals 122D, 122U back to downlink and uplink electrical data services signals 98D, 98U. The corresponding signal conversion at the remote site is happening within the PvAU 14 in a separate module (see a converter module 216 in FIG. 10). This converter module 216 could also contain PoE capability in order to electrically power remote Ethernet equipment connected to the RAU 14, such as AUs 118. In one embodiment, the converter 204 can be located separately from the RAUs 14.

[0070] In this manner, the transmission of the digital services data signals from and to the RAUs 14 may be done on the pair of copper wires 60, 62 in the electrical power line 58 used to power the RAU 14 remotely from the ICU 85.

[0071] Using the available transmission technologies, Fast Ethernet (100BASE-T) could easily be supported. Newer standards like the ITU-T G.hn standard may be used to support Gigabit Ethernet.

[0072] FIG. 10 is a schematic diagram of an exemplary interconnect unit (ICU) for converting a received electrical data services signal into an electrical power signal and an exemplary RAU for converting a received electrical power signal back into an electrical data services signal. The ICU 85 may include one or more converter modules 203 and a power supply module 212 for supplying power to an electrical power line 214. The converter module 203 may include a digital data services interface 206, a PLC chip set 208 (such as the Atheros or Actiontec chip sets disclosed above), and a RJ-45 Ethernet connector 210 compatible with PoE. The converter module 203 is configured to receive downlink and uplink electrical digital services data signals 98D, 98U from the digital data services switch 96 at the digital data services interface 206 and uses the PLC chip set 208 and the RJ-45 Ethernet connector 210 to convert the downlink and uplink electrical digital services data signals 98D, 98U to downlink and uplink electrical power signals 122D, 122U. The downlink and uplink electrical power signals 122D, 122U are then transmitted along the electrical power line 214 along with a DC power signal to the RAU 14. The electrical power line 214 may be in an array cable, such as the array cable 104 in FIG. 4.

[0073] In one embodiment, the RAU 14 may include the converter module 216, two (2) RJ-45 Ethernet connectors 218A and 218B that are compatible with PoE, a power interface 220, a digital data services interface 222, a PLC chip set 224, a DC power module 226, a DC voltage controller 228, and a remote RF module 230. One or more optical fibers 232 carry RF signals from the ICU 85 to the RAU 14, where the remote RF module 230 may propagate the RF signals to devices within range of the remote RF module 230. The electrical power line 214 carries power to the DC voltage controller 228, which regulates and provides the correct voltage to the remote RF module 230, the digital data services interface 222, the PLC chip set 224, and other circuitry in the RAU 14. The PLC chip set 224 in the converter module 216 acts to convert the electrical power signals 122D, 122U received from the electrical power line 214 to digital services data signals, which are provided to the digital data services interface 222.

[0074] In one embodiment, where the digital data services are provided over the Ethernet, the power interface 220 could be provided as a Power-over-Ethernet (PoE) interface, which is coupled to the RJ-45 Ethernet connectors 218A and 218B, which are compatible with PoE as an example. In this manner, the RJ-45 Ethernet connectors 218A and 218B would be able to access both Ethernet digital data services provided by the digital data services interface 222, as well as access power distributed by the ICU 85 as provided by the electrical power line 214.

[0075] Options and alternatives can be provided for the above-described embodiments. A digital data services interface provided in an RAU or stand-alone converter module could include more than one digital data services port. For example, a switch, such as an Ethernet switch, may be disposed in the RAUs 14 to provide RAUs 14 that can support more than one digital data services port. An ICU 85 could have an integrated Ethernet switch so that, for example, several AUs could be attached via cables (e.g., Cat 5/6/7 cables) in a star architecture. An Ethernet channel could be used for control, management, and/or communication purposes for an optical fiber-based distributed communications system as well as the Ethernet media conversion layer. The ICU 85 could be either a single channel or a multi-channel (e.g., twelve (12) channel) solution. The multi-channel solution may be less expensive per channel than a single channel solution. Further, uplink and downlink electrical digital signals can be provided over mediums other than optical fiber, including electrical conducting wire and/or wireless communications, as examples. [0076] Further, as used herein, it is intended that terms "fiber optic cables" and/or "optical fibers" include all types of single mode and multi-mode light waveguides, including one or more optical fibers that may be upcoated, colored, buffered, ribbonized and/or have other organizing or protective structure in a cable such as one or more tubes, strength members, jackets or the like. The optical fibers disclosed herein can be single mode or multi-mode optical fibers. Likewise, other types of suitable optical fibers include bend-insensitive optical fibers, or any other expedient of a medium for transmitting light signals. An example of a bend-insensitive, or bend resistant, optical fiber is ClearCurve^® Multimode fiber commercially available from Corning Incorporated. Suitable fibers of this type are disclosed, for example, in U.S. Patent Application Publication Nos. 2008/0166094 and 2009/0169163, the disclosures of which are incorporated herein by reference in their entireties.

[0077] Many modifications and other embodiments of the embodiments set forth herein will come to mind to one skilled in the art to which the embodiments pertain having the benefit of the teachings presented in the foregoing descriptions and the associated drawings.

Claims

We claim:

1. A distributed antenna system for distributing radio frequency (RF) communications and digital data services (DDSs) to at least one remote antenna unit (RAU), comprising:

head-end unit equipment configured to:

receive at least one downlink electrical RF communications signal;

convert the at least one downlink electrical RF communications signal into at least one downlink optical RF communications signal to be communicated over at least one communications downlink to the at least one RAU;

receive at least one uplink optical RF communications signal over at least one communications uplink from the at least one RAU; and

convert the at least one uplink optical RF communications signal into at least one uplink electrical RF communications signal; and

an interconnect unit configured to:

receive at least one downlink electrical digital signal containing at least one DDS;

convert the at least one downlink electrical digital signal to an electrical power signal; and

provide the electrical power signal over an electrical power line to the at least one RAU.

2. The distributed antenna system of claim 1 , wherein the interconnect unit is farther configured to receive the least one downlink electrical digital signal from an Ethernet switch.

3. The distributed antenna system of claim 1 , wherein the interconnect unit is farther configured to receive at least one uplink electrical digital signal containing at least one DDS from the at least one RAU.

4. The distributed antenna system of claim 1 , wherein the interconnect unit is farther configured to provide the at least one uplink electrical digital signal to an Ethernet switch.

5. The distributed antenna system of claim 1 , wherein the at least one RAU is further configured to:

convert the at least one downlink electrical power signal back to the at least one downlink electrical digital signal containing at least one DDS; and

provide the at least one DDS.

6. The distributed antenna system of claim 2, wherein the electrical power line also provides power to the at least one RAU.

7. The distributed antenna system of claim 3, wherein the at least one RAU further comprises a power interface configured to receive electrical power from the electrical power line and provide the electrical power to at least one port to provide access to power for digital data service clients.

8. The distributed antenna system of claim 1 , wherein the at least one DDS is comprised from the group consisting of Ethernet, Wireless Local Area Network (WLAN), Worldwide Interoperability for Microwave Access (WiMax), Digital Subscriber Line (DSL), and Long Term Evolution (LTE).

9. The distributed antenna system of claim 1 , wherein the at least one communications downlink and the at least one communications uplink include optical fiber.

10. The distributed antenna system of claim 1 , wherein the electrical power line is in a fiber optic cable that is part of the at least one communications downlink that carries the at least one downlink optical RF communications signal or the at least one communication uplink that carries the at least one uplink optical RF communications signal.

11. The distributed antenna system of claim 1 , wherein the electrical power line is in a fiber optic cable that is separate from the at least one communications downlink that carries the at least one downlink optical RF communications signal and the at least one communication uplink that carries at the least one uplink optical RF communications signal.

12. The distributed antenna system of claim 1 , wherein the interconnect unit and the RAU each include an Ethernet over Powerline converter for converting the at least one downlink electrical digital signal to an electrical power signal.

13. The distributed antenna system of claim 1 , wherein the interconnect unit and the RAU each include Powerline Communication chip sets for converting the at least one downlink electrical digital signal to an electrical power signal.

14. A method of distributing radio frequency (RF) communications and digital data services (DDSs) to at least one remote antenna unit (RAU) in a distributed antenna system, comprising:

receiving at head-end equipment at least one downlink electrical RF communications signal;

converting the at least one downlink electrical RF communications signal into at least one downlink optical RF communications signal to be communicated over at least one communications downlink to the at least one RAU;

receiving at the head-end equipment at least one uplink optical RF communications signal over at least one communications uplink from the at least one RAU;

converting the at least one uplink optical RF communications signal into at least one uplink electrical RF communications signal; receiving at an interconnect unit at least one downlink electrical digital signal containing at least one DDS;

converting the at least one downlink electrical digital signal to an electrical power signal; and

providing the electrical power signal over an electrical power line to the at least one RAU.

15. The method of claim 14, further comprising receiving at the interconnect unit the least one downlink electrical digital signal from an Ethernet switch.

16. The method of claim 14, further comprising receiving at the interconnect unit at least one uplink electrical digital signal containing at least one DDS from the at least one RAU.

17. The method of claim 14, further comprising the interconnect unit providing the at least one uplink electrical digital signal to an Ethernet switch.

18. The method of claim 14, further comprising:

receiving the electrical power signal at the at least one RAU;

converting the electrical power signal back to the at least one downlink electrical digital signal containing at least one DDS; and

providing the at least one DDS.

19. The method of claim 14, further comprising providing power to the RAU over the electrical power line.

20. The method of claim 14, further comprising providing power to at least one port of the RAU to provide access to power to digital data services clients.

21. The method of claim 14, wherein the converting the at least one downlink electrical digital signal to the electrical power signal is performed using Powerline Communication (PLC).

22. A remote antenna unit (RAU) for use in a distributed antenna system, comprising: an optical-to-electrical (O/E) converter configured to convert received downlink optical radio frequency (RF) communications signals to downlink electrical RF communications signals and provide the downlink electrical RF communications signals to at least one first port;

an electrical- to-optical (E/O) converter configured to convert uplink electrical RF communications signals received from the at least one first port to uplink optical RF communications signals; and

a power converter coupled to at least one second port and configured to:

receive an electrical power signal over an electrical power line;

convert the electrical power signal to at least one downlink electrical digital signal containing at least one digital data service (DDS); and

provide the at least one downlink electrical digital signal to at least one third port such that the at least one DDS may be provided.

23. The remote antenna unit of claim 22, wherein the downlink optical RF communications signals are received over at least one first communications downlink connected to head-end equipment.

24. The remote antenna unit of claim 22, wherein the RAU further comprises a power interface configured to receive electrical power from the electrical power line and provide the electrical power to the at least one second port.

25. The remote antenna unit of claim 24, wherein the at least one second port is configured to support Power-over-Ethernet (PoE).

26. The remote antenna unit of claim 22, wherein the electrical power line is provided in at least one array cable.

27. An interconnect unit for use in a distributed antenna system, comprising:

a first interface configured to receive at least one downlink electrical digital signal containing at least one digital data service (DDS); and

a power converter coupled to the second interface and configured to convert the at least one downlink electrical digital signal containing the at least one DDS into an electrical power signal for transmission on an electrical power line coupled to the interconnect unit toward a remote antenna unit.

28. The interconnect unit of claim 27, further comprising a second interface configured to receive at least one downlink optical radio frequency (RF) communications signal from head-end equipment.

29. The interconnect unit of claim 27, wherein the first interface is further configured to receive the least one downlink electrical digital signal from an Ethernet switch.

30. The interconnect unit of claim 27, further comprising a third interface configured to receive at least one uplink electrical digital signal containing at least one DDS from the at least one RAU.