US20110077501A1

US20110077501A1 - Micro mri unit

Info

Publication number: US20110077501A1
Application number: US12/848,812
Authority: US
Inventors: Ahmadreza (Reza) Rofougaran
Original assignee: Broadcom Corp
Current assignee: Avago Technologies International Sales Pte Ltd
Priority date: 2009-09-30
Filing date: 2010-08-02
Publication date: 2011-03-31
Also published as: US20110077697A1; US20110077716A1; US20120323088A1; US20110077476A1; US20150314116A1; US20110077623A1; US20110077718A1; US20110077502A1; US20110077513A1; US9111021B2; US20110077459A1; US8489199B2; US9081878B2; US8254853B2; US8526894B2; US20110077713A1; US20110077715A1; US20110076983A1; US20110077714A1; US20110077700A1

Abstract

A micro magnetic resonance imaging (MRI) unit includes a gradient magnetic field bio-medical unit, a transmitting bio-medical unit, and a receiving bio-medical unit. The gradient magnetic field bio-medical unit is operable to generate a gradient magnetic field in a proximal area of a body object within a host body, wherein a constant magnetic field is present in the proximal area of the body object. The transmitting bio-medical unit is operable to transmit a varying radio frequency (RF) signal in a direction of the body object. The receiving bio-medical unit is operable to: receive a representation of the varying RF signal; process the representation of the varying RF signal to produce a processed signal; and output the processed signal, wherein at least one of the gradient magnetic field bio-medical unit, the transmitting bio-medical unit, and the receiving bio-medical unit is implanted in a host body.

Description

CROSS REFERENCE TO RELATED APPLICATIONS

This patent application is claiming priority under 35 USC §119 to a provisionally filed patent application entitled BIO-MEDICAL UNIT AND APPLICATIONS THEREOF, having a provisional filing date of Sep. 30, 2009, and a provisional Ser. No. 61/247,060.

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

NOT APPLICABLE

INCORPORATION-BY-REFERENCE OF MATERIAL SUBMITTED ON A COMPACT DISC

NOT APPLICABLE

BACKGROUND OF THE INVENTION

1. Technical Field of the Invention
This invention relates generally to medical equipment and more particularly to wireless medical equipment.
2. Description of Related Art
As is known, there is a wide variety of medical equipment that aids in the diagnosis, monitoring, and/or treatment of patients' medical conditions. For instances, there are diagnostic medical devices, therapeutic medical devices, life support medical devices, medical monitoring devices, medical laboratory equipment, etc. As specific exampled magnetic resonance imaging (MRI) devices produce images that illustrate the internal structure and function of a body.
The advancement of medical equipment is in step with the advancements of other technologies (e.g., radio frequency identification (RFID), robotics, etc.). Recently, RFID technology has been used for in vitro use to store patient information for easy access. While such in vitro applications have begun, the technical advancement in this area is in its infancy.

BRIEF SUMMARY OF THE INVENTION

The present invention is directed to apparatus and methods of operation that are further described in the following Brief Description of the Drawings, the Detailed Description of the Invention, and the claims. Other features and advantages of the present invention will become apparent from the following detailed description of the invention made with reference to the accompanying drawings.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING(S)

FIG. 1 is a diagram of an embodiment of a system in accordance with the present invention;

FIG. 2 is a diagram of another embodiment of a system in accordance with the present invention;

FIG. 3 is a diagram of an embodiment of an artificial body part including one or more bio-medical units in accordance with the present invention;

FIG. 4 is a schematic block diagram of an embodiment of an artificial body part in accordance with the present invention;

FIG. 5 is a diagram of another embodiment of a system in accordance with the present invention;

FIG. 6 is a diagram of another embodiment of a system in accordance with the present invention;

FIG. 7 is a diagram of another embodiment of a system in accordance with the present invention;

FIG. 8 is a schematic block diagram of an embodiment of a bio-medical unit in accordance with the present invention;

FIG. 9 is a schematic block diagram of an embodiment of a power harvesting module in accordance with the present invention;

FIG. 10 is a schematic block diagram of another embodiment of a power harvesting module in accordance with the present invention;

FIG. 11 is a schematic block diagram of another embodiment of a power harvesting module in accordance with the present invention;

FIG. 12 is a schematic block diagram of another embodiment of a power harvesting module in accordance with the present invention;

FIG. 13 is a schematic block diagram of an embodiment of a power boost module in accordance with the present invention;

FIG. 14 is a schematic block diagram of an embodiment of an electromagnetic (EM)) power harvesting module in accordance with the present invention;

FIG. 15 is a schematic block diagram of another embodiment of an electromagnetic (EM)) power harvesting module in accordance with the present invention;

FIG. 16 is a schematic block diagram of another embodiment of a bio-medical unit in accordance with the present invention;

FIG. 17 is a diagram of another embodiment of a system in accordance with the present invention;

FIG. 18 is a diagram of an example of a communication protocol within a system in accordance with the present invention;

FIG. 19 is a diagram of another embodiment of a system in accordance with the present invention;

FIG. 20 is a diagram of another example of a communication protocol within a system in accordance with the present invention;

FIG. 21 is a diagram of an embodiment of a micro MRI unit in accordance with the present invention;

FIG. 22 is a logic diagram of an embodiment of a method for execution by a processing module in accordance with the present invention;

FIG. 23 is a logic diagram of an embodiment of a method for MMW communications within a MRI sequence in accordance with the invention;

FIG. 24 is a logic diagram of an embodiment of a method for processing of MRI signals in accordance with the present invention;

FIG. 25 is a logic diagram of an embodiment of a method for communication utilizing MRI signals in accordance with the present invention; and

FIG. 26 is a diagram of another embodiment of a micro MRI unit in accordance with the present invention.

DETAILED DESCRIPTION OF THE INVENTION

FIG. 1 is a diagram of an embodiment of a system that includes a plurality of bio-medical units 10 embedded within a body and/or placed on the surface of the body to facilitate diagnosis, treatment, and/or data collections. Each of the bio-medical units 10 is a passive device (e.g., it does not include a power source (e.g., a battery)) and, as such, includes a power harvesting module. The bio-medical units 10 may also include one or more of memory, a processing module, and functional modules. Alternatively, or in addition to, each of the bio-medical units 10 may include a rechargeable power source.
In operation, a transmitter 12 emits electromagnetic signals 16 that pass through the body and are received by a receiver 14. The transmitter 12 and receiver 14 may be part of a piece of medical diagnostic equipment (e.g., magnetic resonance imaging (MRI), X-ray, etc.) or independent components for stimulating and communicating with the network of bio-medical units in and/or on a body. One or more of the bio-medical units 10 receives the transmitted electromagnetic signals 16 and generates a supply voltage therefrom. Examples of this will be described in greater detail with reference to FIGS. 8-12.
Embedded within the electromagnetic signals 16 (e.g., radio frequency (RF) signals, millimeter wave (MMW) signals, MRI signals, etc.) or via separate signals, the transmitter 12 communicates with one or more of the bio-medical units 10. For example, the electromagnetic signals 16 may have a frequency in the range of a few MHz to 900 MHz and the communication with the bio-medical units 10 is modulated on the electromagnetic signals 16 at a much higher frequency (e.g., 5 GHz to 300 GHz). As another example, the communication with the bio-medical units 10 may occur during gaps (e.g., per protocol of medical equipment or injected for communication) of transmitting the electromagnetic signals 16. As another example, the communication with the bio-medical units 10 occurs in a different frequency band and/or using a different transmission medium (e.g., use RF or MMW signals when the magnetic field of the electromagnetic signals are dominate, use ultrasound signals when the electromagnetic signals 16 are RF and/or MMW signals, etc.).
One or more of the bio-medical units 10 receives the communication signals 18 and processes them accordingly. The communication signals 18 may be instructions to collect data, to transmit collected data, to move the unit's position in the body, to perform a function, to administer a treatment, etc. If the received communication signals 18 require a response, the bio-medical unit 10 prepares an appropriate response and transmits it to the receiver 14 using a similar communication convention used by the transmitter 12.
FIG. 2 is a diagram of another embodiment of a system that includes a plurality of bio-medical units 10 embedded within a body and/or placed on the surface of the body to facilitate diagnosis, treatment, and/or data collections. Each of the bio-medical units 10 is a passive device and, as such, includes a power harvesting module. The bio-medical units 10 may also include one or more of memory, a processing module, and functional modules. In this embodiment, the person is placed in an MRI machine (fixed or portable) that generates a magnetic field 26 through which the MRI transmitter 20 transmits MRI signals 28 to the MRI receiver 22.
One or more of the bio-medical units 10 powers itself by harvesting energy from the magnetic field 26 or changes thereof as produced by gradient coils, from the magnetic fields of the MRI signals 28, from the electrical fields of the MRI signals 28, and/or from the electromagnetic aspects of the MRI signals 28. A unit 10 converts the harvested energy into a supply voltage that supplies other components of the unit (e.g., a communication module, a processing module, memory, a functional module, etc.).
A communication device 24 communicates data and/or control communications 30 with one or more of the bio-medical units 10 over one or more wireless links. The communication device 24 may be a separate device from the MRI machine or integrated into the MRI machine. For example, the communication device 24, whether integrated or separate, may be a cellular telephone, a computer with a wireless interface (e.g., a WLAN station and/or access point, Bluetooth, a proprietary protocol, etc.), etc. A wireless link may be one or more frequencies in the ISM band, in the 60 GHz frequency band, the ultrasound frequency band, and/or other frequency bands that supports one or more communication protocols (e.g., data modulation schemes, beamforming, RF or MMW modulation, encoding, error correction, etc.).
The composition of the bio-medical units 10 includes non-ferromagnetic materials (e.g., paramagnetic or diamagnetic) and/or metal alloys that are minimally affected by an external magnetic field 26. In this regard, the units harvest power from the MRI signals 28 and communicate using RF and/or MMW electromagnetic signals with negligible chance of encountering the projectile or missile effect of implants that include ferromagnetic materials.
FIG. 3 is a diagram of an embodiment of an artificial body part 32 including one or more bio-medical units 10 that may be surgically implanted into a body. The artificial body part 32 may be a pace maker, a breast implant, a joint replacement, an artificial bone, splints, fastener devices (e.g., screws, plates, pins, sutures, etc.), artificial organ, etc. The artificial body part 32 may be permanently embedded in the body or temporarily embedded into the body.
FIG. 4 is a schematic block diagram of an embodiment of an artificial body part 32 that includes one or more bio-medical units 10. For instance, one bio-medical unit 10 may be used to detect infections, the body's acceptance of the artificial body part 32, measure localized body temperature, monitor performance of the artificial body part 32, and/or data gathering for other diagnostics. Another bio-medical unit 10 may be used for deployment of treatment (e.g., disperse medication, apply electrical stimulus, apply RF radiation, apply laser stimulus, etc.). Yet another bio-medical unit 10 may be used to adjust the position of the artificial body part 32 and/or a setting of the artificial body part 32. For example, a bio-medical unit 10 may be used to mechanically adjust the tension of a splint, screws, etc. As another example, a bio-medical unit 10 may be used to adjust an electrical setting of the artificial body part 32.
FIG. 5 is a diagram of another embodiment of a system that includes a plurality of bio-medical units 10 and one or more communication devices 24 coupled to a wide area network (WAN) communication device 34 (e.g., a cable modem, DSL modem, base station, access point, hot spot, etc.). The WAN communication device 34 is coupled to a network 42 (e.g., cellular telephone network, internet, etc.), which has coupled to it a plurality of remote monitors 36, a plurality of databases 40, and a plurality of computers 38. The communication device 24 includes a processing module and a wireless transceiver module (e.g., one or more transceivers) and may function similarly to communication module 48 as described in FIG. 8,
In this system, one or more bio-medical units 10 are implanted in, or affixed to, a host body (e.g., a person, an animal, genetically grown tissue, etc.). As previously discussed and will be discussed in greater detail with reference to one or more of the following figures, a bio-medical unit includes a power harvesting module, a communication module, and one or more functional modules. The power harvesting module operable to produce a supply voltage from a received electromagnetic power signal (e.g., the electromagnetic signal 16 of FIGS. 1 and 2, the MRI signals of one or more the subsequent figures). The communication module and the at least one functional module are powered by the supply voltage.
In an example of operation, the communication device 24 (e.g., integrated into an MRI machine, a cellular telephone, a computer with a wireless interface, etc.) receives a downstream WAN signal from the network 42 via the WAN communication device 34. The downstream WAN signal may be generated by a remote monitoring device 36, a remote diagnostic device (e.g., computer 38 performing a remote diagnostic function), a remote control device (e.g., computer 38 performing a remote control function), and/or a medical record storage device (e.g., database 40).
The communication device 24 converts the downstream WAN signal into a downstream data signal. For example, the communication device 24 may convert the downstream WAN signal into a symbol stream in accordance with one or more wireless communication protocols (e.g., GSM, CDMA, WCDMA, HSUPA, HSDPA, WiMAX, EDGE, GPRS, IEEE 802.11, Bluetooth, ZigBee, universal mobile telecommunications system (UMTS), long term evolution (LTE), IEEE 802.16, evolution data optimized (EV-DO), etc.). The communication device 24 may convert the symbol stream into the downstream data signal using the same or a different wireless communication protocol.
Alternatively, the communication device 24 may convert the symbol stream into data that it interprets to determine how to structure the communication with the bio-medical unit 10 and/or what data (e.g., instructions, commands, digital information, etc.) to include in the downstream data signal. Having determined how to structure and what to include in the downstream data signal, the communication device 24 generates the downstream data signal in accordance with one or more wireless communication protocols. As yet another alternative, the communication device 24 may function as a relay, which provides the downstream WAN signal as the downstream data signal to the one or more bio-medical units 10.
When the communication device 24 has (and/or is processing) the downstream data signal to send to the bio-medical unit, it sets up a communication with the bio-medical unit. The set up may include identifying the particular bio-medical unit(s), determining the communication protocol used by the identified bio-medical unit(s), sending a signal to an electromagnetic device (e.g., MRI device, etc.) to request that it generates the electromagnetic power signal to power the bio-medical unit, and/or initiate a communication in accordance with the identified communication protocol. As an alternative to requesting a separate electromagnetic device to create the electromagnetic power signal, the communication device may include an electromagnetic device to create the electromagnetic power signal.
Having set up the communication, the communication device 24 wirelessly communicates the downstream data signal to the communication module of the bio-medical unit 10. The functional module of the bio-medical unit 10 processes the downstream data contained in the downstream data signal to perform a bio-medical functional, to store digital information contained in the downstream data, to administer a treatment (e.g., administer a medication, apply laser stimulus, apply electrical stimulus, etc.), to collect a sample (e.g., blood, tissue, cell, etc.), to perform a micro electro-mechanical function, and/or to collect data. For example, the bio-medical function may include capturing a digital image, capturing a radio frequency (e.g., 300 MHz to 300 GHz) radar image, an ultrasound image, a tissue sample, and/or a measurement (e.g., blood pressure, temperature, pulse, blood-oxygen level, blood sugar level, etc.).
When the downstream data requires a response, the functional module performs a bio-medical function to produce upstream data. The communication module converts the upstream data into an upstream data signal in accordance with the one or more wireless protocols. The communication device 24 converts the upstream data signal into an upstream wide area network (WAN) signal and transmits it to a remote diagnostic device, a remote control device, and/or a medical record storage device. In this manner, a person(s) operating the remote monitors 36 may view images and/or the data 30 gathered by the bio-medical units 10. This enables a specialist to be consulted without requiring the patient to travel to the specialist's office.
In another example of operation, one or more of the computers 38 may communicate with the bio-medical units 10 via the communication device 24, the WAN communication device 34, and the network 42. In this example, the computer 36 may provide commands 30 to one or more of the bio-medical units 10 to gather data, to dispense a medication, to move to a new position in the body, to perform a mechanical function (e.g., cut, grasp, drill, puncture, stitch, patch, etc.), etc. As such, the bio-medical units 10 may be remotely controlled via one or more of the computers 36.
In another example of operation, one or more of the bio-medical units 10 may read and/or write data from or to one or more of the databases 40. For example, data (e.g., a blood sample analysis) generated by one or more of the bio-medical units 10 may be written to one of the databases 40. The communication device 24 and/or one of the computers 36 may control the writing of data to or the reading of data from the database(s) 40. The data may further include medical records, medical images, prescriptions, etc.
FIG. 6 is a diagram of another embodiment of a system that includes a plurality of bio-medical units 10. In this embodiment, the bio-medical units 10 can communicate with each other directly and/or communicate with the communication device 24 directly. The communication medium may be an infrared channel(s), an RF channel(s), a MMW channel(s), and/or ultrasound. The units may use a communication protocol such as token passing, carrier sense, time division multiplexing, code division multiplexing, frequency division multiplexing, etc.
FIG. 7 is a diagram of another embodiment of a system that includes a plurality of bio-medical units 10. In this embodiment, one of the bio-medical units 44 functions as an access point for the other units. As such, the designated unit 44 routes communications between the units 10 and between one or more units 10 and the communication device 24. The communication medium may be an infrared channel(s), an RF channel(s), a MMW channel(s), and/or ultrasound. The units 10 may use a communication protocol such as token passing, carrier sense, time division multiplexing, code division multiplexing, frequency division multiplexing, etc.
FIG. 8 is a schematic block diagram of an embodiment of a bio-medical unit 10 that includes a power harvesting module 46, a communication module 48, a processing module 50, memory 52, and one or more functional modules 54. The processing module 50 may be a single processing device or a plurality of processing devices. Such a processing device may be a microprocessor, micro-controller, digital signal processor, microcomputer, central processing unit, field programmable gate array, programmable logic device, state machine, logic circuitry, analog circuitry, digital circuitry, and/or any device that manipulates signals (analog and/or digital) based on hard coding of the circuitry and/or operational instructions. The processing module 50 may have an associated memory 52 and/or memory element, which may be a single memory device, a plurality of memory devices, and/or embedded circuitry of the processing module. Such a memory device 52 may be a read-only memory, random access memory, volatile memory, non-volatile memory, static memory, dynamic memory, flash memory, cache memory, and/or any device that stores digital information. Note that if the processing module 50 includes more than one processing device, the processing devices may be centrally located (e.g., directly coupled together via a wired and/or wireless bus structure) or may be distributedly located (e.g., cloud computing via indirect coupling via a local area network and/or a wide area network). Further note that when the processing module 50 implements one or more of its functions via a state machine, analog circuitry, digital circuitry, and/or logic circuitry, the memory and/or memory element storing the corresponding operational instructions may be embedded within, or external to, the circuitry comprising the state machine, analog circuitry, digital circuitry, and/or logic circuitry. Still further note that, the memory element stores, and the processing module executes, hard coded and/or operational instructions corresponding to at least some of the steps and/or functions illustrated in FIGS. 1-26.
The power harvesting module 46 may generate one or more supply voltages 56 (Vdd) from a power source signal (e.g., one or more of MRI electromagnetic signals 16, magnetic fields 26, RF signals, MMW signals, ultrasound signals, light signals, and body motion). The power harvesting module 46 may be implemented as disclosed in U.S. Pat. No. 7,595,732 to generate one or more supply voltages from an RF signal. The power harvesting module 46 may be implemented as shown in one or more FIGS. 9-11 to generate one or more supply voltages 56 from an MRI signal 28 and/or magnetic field 26. The power harvesting module 46 may be implemented as shown in FIG. 12 to generate one or more supply voltage 56 from body motion. Regardless of how the power harvesting module generates the supply voltage(s), the supply voltage(s) are used to power the communication module 48, the processing module 50, the memory 52, and/or the functional modules 54.
In an example of operation, a receiver section of the communication module 48 receives an inbound wireless communication signal 60 and converts it into an inbound symbol stream. For example, the receiver section amplifies an inbound wireless (e.g., RF or MMW) signal 60 to produce an amplified inbound RF or MMW signal. The receiver section may then mix in-phase (I) and quadrature (Q) components of the amplified inbound RF or MMW signal with in-phase and quadrature components of a local oscillation to produce a mixed I signal and a mixed Q signal. The mixed I and Q signals are combined to produce an inbound symbol stream. In this embodiment, the inbound symbol may include phase information (e.g., +/−Δθ [phase shift] and/or θ(t) [phase modulation]) and/or frequency information (e.g., +/−Δf [frequency shift] and/or f(t) [frequency modulation]). In another embodiment and/or in furtherance of the preceding embodiment, the inbound RF or MMW signal includes amplitude information (e.g., +/−ΔA [amplitude shift] and/or A(t) [amplitude modulation]). To recover the amplitude information, the receiver section includes an amplitude detector such as an envelope detector, a low pass filter, etc.
The processing module 50 converts the inbound symbol stream into inbound data and generates a command message based on the inbound data. The command message may instruction one or more of the functional modules to perform one or more electro-mechanical functions of gathering data (e.g., imaging data, flow monitoring data), dispensing a medication, moving to a new position in the body, performing a mechanical function (e.g., cut, grasp, drill, puncture, stitch, patch, etc.), dispensing a treatment, collecting a biological sample, etc.
To convert the inbound symbol stream into the inbound data (e.g., voice, text, audio, video, graphics, etc.), the processing module 50 may perform one or more of: digital intermediate frequency to baseband conversion, time to frequency domain conversion, space-time-block decoding, space-frequency-block decoding, demodulation, frequency spread decoding, frequency hopping decoding, beamforming decoding, constellation demapping, deinterleaving, decoding, depuncturing, and/or descrambling. Such a conversion is typically prescribed by one or more wireless communication standards (e.g., GSM, CDMA, WCDMA, HSUPA, HSDPA, WiMAX, EDGE, GPRS, IEEE 802.11, Bluetooth, ZigBee, universal mobile telecommunications system (UMTS), long term evolution (LTE), IEEE 802.16, evolution data optimized (EV-DO), etc.).
The processing module 50 provides the command message to one or more of the micro-electromechanical functional modules 54. The functional module 54 performs an electro-mechanical function within a hosting body in accordance with the command message. Such an electro-mechanical function includes at least one of data gathering (e.g., image, flow monitoring), motion, repairs, dispensing medication, biological sampling, diagnostics, applying laser treatment, applying ultrasound treatment, grasping, sawing, drilling, providing an electronic stimulus etc. Note that the functional modules 54 may be implemented using nanotechnology and/or microelectronic mechanical systems (MEMS) technology.
When requested per the command message (e.g. gather data and report the data), the micro electro-mechanical functional module 54 generates an electro-mechanical response based on the performing the electro-mechanical function. For example, the response may be data (e.g., heart rate, blood sugar levels, temperature, blood flow rate, image of a body object, etc.), a biological sample (e.g., blood sample, tissue sample, etc.), acknowledgement of performing the function (e.g., acknowledge a software update, storing of data, etc.), and/or any appropriate response. The micro electro-mechanical functional module 54 provides the response to the processing module 50.
The processing module 50 converts the electro-mechanical response into an outbound symbol stream, which may be done in accordance with one or more wireless communication standards (e.g., GSM, CDMA, WCDMA, HSUPA, HSDPA, WiMAX, EDGE, GPRS, IEEE 802.11, Bluetooth, ZigBee, universal mobile telecommunications system (UMTS), long term evolution (LTE), IEEE 802.16, evolution data optimized (EV-DO), etc.). Such a conversion includes one or more of: scrambling, puncturing, encoding, interleaving, constellation mapping, modulation, frequency spreading, frequency hopping, beamforming, space-time-block encoding, space-frequency-block encoding, frequency to time domain conversion, and/or digital baseband to intermediate frequency conversion.
A transmitter section of the communication module 48 converts an outbound symbol stream into an outbound RF or MMW signal 60 that has a carrier frequency within a given frequency band (e.g., 900 MHz, 2.5 GHz, 5 GHz, 57-66 GHz, etc.). In an embodiment, this may be done by mixing the outbound symbol stream with a local oscillation to produce an up-converted signal. One or more power amplifiers and/or power amplifier drivers amplifies the up-converted signal, which may be RF or MMW bandpass filtered, to produce the outbound RF or MMW signal 60. In another embodiment, the transmitter section includes an oscillator that produces an oscillation. The outbound symbol stream provides phase information (e.g., +/−Δθ [phase shift] and/or θ(t) [phase modulation]) that adjusts the phase of the oscillation to produce a phase adjusted RF or MMW signal, which is transmitted as the outbound RF signal 60. In another embodiment, the outbound symbol stream includes amplitude information (e.g., A(t) [amplitude modulation]), which is used to adjust the amplitude of the phase adjusted RF or MMW signal to produce the outbound RF or MMW signal 60.
In yet another embodiment, the transmitter section includes an oscillator that produces an oscillation. The outbound symbol provides frequency information (e.g., +/−Δf [frequency shift] and/or f(t) [frequency modulation]) that adjusts the frequency of the oscillation to produce a frequency adjusted RF or MMW signal, which is transmitted as the outbound RF or MMW signal 60. In another embodiment, the outbound symbol stream includes amplitude information, which is used to adjust the amplitude of the frequency adjusted RF or MMW signal to produce the outbound RF or MMW signal 60. In a further embodiment, the transmitter section includes an oscillator that produces an oscillation. The outbound symbol provides amplitude information (e.g., +/−AA [amplitude shift] and/or A(t) [amplitude modulation) that adjusts the amplitude of the oscillation to produce the outbound RF or MMW signal 60.
Note that the bio-medical unit 10 may be encapsulated by an encapsulate 58 that is non-toxic to the body. For example, the encapsulate 58 may be a silicon based product, a non-ferromagnetic metal alloy (e.g., stainless steel), etc. As another example, the encapsulate 58 may include a spherical shape and have a ferromagnetic liner that shields the unit from a magnetic field and to offset the forces of the magnetic field. Further note that the bio-medical unit 10 may be implemented on a single die that has an area of a few millimeters or less. The die may be fabricated in accordance with CMOS technology, Gallium-Arsenide technology, and/or any other integrated circuit die fabrication process.
In another example of operation, one of the functional modules 54 functions as a first micro-electro mechanical module and another one of the functions modules 54 functions as a second micro-electro mechanical module. In this example, the bio-medical unit is implanted into a host body (e.g., a person, an animal, a reptile, etc.) at a position proximal to a body object to be monitored and/or have an image taken thereof. For example, the body object may be a vein, an artery, an organ, a cyst (or other growth), etc. As a specific example, the bio-medical unit may be positioned approximately parallel to the flow of blood in a vein, artery, and/or the heart.
When powered by the supply voltage, the first micro-electro mechanical module generates and transmits a wireless signal at, or around, the body object. The second micro-electro mechanical module receives a representation of the wireless signal (e.g., a reflection of the wireless signal, a refraction of the wireless signal, or a determined absorption of the wireless signal). Note that the wireless signal may be an ultrasound signal, a radio frequency signal, and/or a millimeter wave signal.
The processing module 50 may coordinate the transmitting of the wireless signal and the receiving of the representation of the wireless signal. For example, the processing module may receive, via the communication module, a command to enable the transmitting of the wireless signal (e.g., an ultrasound signal) and the receiving of the representation of the wireless signal. In response, the processing module generates a control signal that it provides to the first micro-electro mechanical module to enable it to transmit the wireless signal.
In addition, the processing module may generate flow monitoring data based on the second micro-electro mechanical module receiving of the representation of the wireless signal. As a specific example, the processing module calculates a fluid flow rate based on phase shifting and/or frequency shifting between the transmitting of the wireless signal and the receiving of the representation of the wireless signal. As another specific example, the processing module gathers phase shifting data and/or frequency shifting data based on the transmitting of the wireless signal and the receiving of the representation of the wireless signal.
The processing module may further generate imaging data based on the second micro-electro mechanical module receiving the representation of the wireless signal. As a specific example, the processing module calculates an image of the body object based absorption of the wireless signal by the body object and/or vibration of the body object. As another specific example, the processing module gathers data regarding the absorption of the wireless signal by the body object and/or of the vibration of the body object.
While the preceding examples of a bio-medical unit including first and second micro-electro mechanical modules for transmitting and receiving wireless signals (e.g., ultrasound, RF, MMW, etc.), a bio-medical unit may include one or the other module. For example, a bio-medical unit may include a micro-electro mechanical module for transmitting a wireless signal, where the receiver is external to the body or in another bio-medical unit. As another example, a bio-medical unit may include a micro-electro mechanical module for receiving a representation of a wireless signal, where the transmitter is external to the body or another bio-medical unit.
FIG. 9 is a schematic block diagram of an embodiment of a power harvesting module 46 that includes an array of on-chip air core inductors 64, a rectifying circuit 66, capacitors, and a regulation circuit 68. The inductors 64 may each having an inductance of a few nano-Henries to a few micro-Henries and may be coupled in series, in parallel, or a series parallel combination.
In an example of operation, the MRI transmitter 20 transmits MRI signals 28 at a frequency of 3-45 MHz at a power level of up to 35 KWatts. The air core inductors 64 are electromagnetically coupled to generate a voltage from the magnetic and/or electric field generated by the MRI signals 28. Alternatively, or in addition to, the air core inductors 64 may generate a voltage from the magnetic field 26 and changes thereof produced by the gradient coils. The rectifying circuit 66 rectifies the AC voltage produced by the inductors to produce a first DC voltage. The regulation circuit generates one or more desired supply voltages 56 from the first DC voltage.
The inductors 64 may be implemented on one more metal layers of the die and include one or more turns per layer. Note that trace thickness, trace length, and other physical properties affect the resulting inductance.
FIG. 10 is a schematic block diagram of another embodiment of a power harvesting module 46 that includes a plurality of on-chip air core inductors 70, a plurality of switching units (S), a rectifying circuit 66, a capacitor, and a switch controller 72. The inductors 70 may each having an inductance of a few nano-Henries to a few micro-Henries and may be coupled in series, in parallel, or a series parallel combination.
In an example of operation, the MRI transmitter 20 transmits MRI signals 28 at a frequency of 3-45 MHz at a power level of up to 35 KWatts. The air core inductors 70 are electromagnetically coupled to generate a voltage from the magnetic and/or electric field generated by the MRI signals 28. The switching module 72 engages the switches via control signals 74 to couple the inductors 70 in series and/or parallel to generate a desired AC voltage. The rectifier circuit 66 and the capacitor(s) convert the desired AC voltage into the one or more supply voltages 56.
FIG. 11 is a schematic block diagram of another embodiment of a power harvesting module 46 that includes a plurality of Hall effect devices 76, a power combining module 78, and a capacitor(s). In an example of operation, the Hall effect devices 76 generate a voltage based on the constant magnetic field (H) and/or a varying magnetic field. The power combining module 78 (e.g., a wire, a switch network, a transistor network, a diode network, etc.) combines the voltages of the Hall effect devices 76 to produce the one or more supply voltages 56.
FIG. 12 is a schematic block diagram of another embodiment of a power harvesting module 46 that includes a plurality of piezoelectric devices 82, a power combining module 78, and a capacitor(s). In an example of operation, the piezoelectric devices 82 generate a voltage based on body movement, ultrasound signals, movement of body fluids, etc. The power combining module 78 (e.g., a wire, a switch network, a transistor network, a diode network, etc.) combines the voltages of the Hall effect devices 82 to produce the one or more supply voltages 56. Note that the piezoelectric devices 82 may include one or more of a piezoelectric motor, a piezoelectric actuator, a piezoelectric sensor, and/or a piezoelectric high voltage device.
The various embodiments of the power harvesting module 46 may be combined to generate more power, more supply voltages, etc. For example, the embodiment of FIG. 9 may be combined with one or more of the embodiments of FIGS. 11 and 12.
FIG. 13 is a schematic block diagram of an embodiment of a power boost module 84 that harvests energy from MRI signals 28 and converts the energy into continuous wave (CW) RF (e.g., up to 3 GHz) and/or MMW (e.g., up to 300 GHz) signals 92 to provide power to the implanted bio-medical units 10. The power boost module 84 sits on the body of the person under test or treatment and includes an electromagnetic power harvesting module 86 and a continuous wave generator 88. In such an embodiment, the power boosting module 84 can recover significantly more energy than a bio-medical unit 10 since it can be significantly larger. For example, a bio-medical unit 10 may have an area of a few millimeters squared while the power boosting module 84 may have an area of a few to tens of centimeters squared.
FIG. 14 is a schematic block diagram of an embodiment of an electromagnetic (EM)) power harvesting module 86 that includes inductors, diodes (or transistors) and a capacitor. The inductors may each be a few mili-Henries such that the power boost module can deliver up to 10's of mili-watts of power.
FIG. 15 is a schematic block diagram of another embodiment of an electromagnetic (EM)) power harvesting module 86 that includes a plurality of Hall effect devices 76, a power combining module 78, and a capacitor. This functions as described with reference to FIG. 11, but the Hall effect devices 76 can be larger such that more power can be produced. Note that the EM power harvesting module 86 may include a combination of the embodiment of FIG. 14 and the embodiment of FIG. 15.
FIG. 16 is a schematic block diagram of another embodiment of a bio-medical unit 10 that includes a power harvesting module 46, a communication module 48, a processing module 50, memory 52, and may include one or more functional modules 54 and/or a Hall effect communication module 116. The communication module 48 may include one or more of an ultrasound transceiver 118 (i.e., a receiver and a transmitter), an electromagnetic transceiver 122, an RF and/or MMW transceiver 120, and a light source (LED) transceiver 124. Note that examples of the various types of communication modules 48 will be described in greater detail with reference to one or more of the subsequent Figures.
The one or more functional modules 54 may perform a repair function, an imaging function, and/or a leakage detection function, which may utilize one or more of a motion propulsion module 96, a camera module 98, a sampling robotics module 100, a treatment robotics module 102, an accelerometer module 104, a flow meter module 106, a transducer module 108, a gyroscope module 110, a high voltage generator module 112, a control release robotics module 114, and/or other functional modules described with reference to one or more other figures. The functional modules 54 may be implemented using MEMS technology and/or nanotechnology. For example, the camera module 98 may be implemented as a digital image sensor in MEMS technology.
The Hall effect communication module 116 utilizes variations in the magnetic field and/or electrical field to produce a plus or minus voltage, which can be encoded to convey information. For example, the charge applied to one or more Hall effect devices 76 may be varied to produce the voltage change. As another example, an MRI transmitter 20 and/or gradient unit may modulate a signal on the magnetic field 26 it generates to produce variations in the magnetic field 26.
FIG. 17 is a diagram of another embodiment of a system that includes one or more bio-medical units 10, a transmitter unit 126, and a receiver unit 128. Each of the bio-medical units 10 includes a power harvesting module 46, a MMW transceiver 138, a processing module 50, and memory 52. The transmitter unit 126 includes a MRI transmitter 130 and a MMW transmitter 132. The receiver unit 128 includes a MRI receiver 134 and a MMW receiver 136. Note that the MMW transmitter 132 and MMW receiver 136 may be in the same unit (e.g., in the transmitter unit, in the receiver unit, or housed in a separate device).
In an example of operation, the bio-medical unit 10 recovers power from the electromagnetic (EM) signals 146 transmitted by the MRI transmitter 130 and communicates via MMW signals 148-150 with the MMW transmitter 132 and MMW receiver 136. The MRI transmitter 130 may be part of a portable MRI device, may be part of a full sized MRI machine, and/or part of a separate device for generating EM signals 146 for powering the bio-medical unit 10.
FIG. 18 is a diagram of an example of a communication protocol within the system of FIG. 17. In this diagram, the MRI transmitter 20 transmits RF signals 152, which have a frequency in the range of 3-45 MHz, at various intervals with varying signal strengths. The power harvesting module 46 of the bio-medical units 10 may use these signals to generate power for the bio-medical unit 10.
In addition to the MRI transmitter 20 transmitting its signal, a constant magnetic field and various gradient magnetic fields 154-164 are created (one or more in the x dimension Gx, one or more in the y dimension Gy, and one or more in the z direction Gz). The power harvesting module 46 of the bio-medical unit 10 may further use the constant magnetic field and/or the varying magnetic fields 154-164 to create power for the bio-medical unit 10.
During non-transmission periods of the cycle, the bio-medical unit 10 may communicate 168 with the MMW transmitter 132 and/or MMW receiver 136. In this regard, the bio-medical unit 10 alternates from generating power to MMW communication in accordance with the conventional transmission-magnetic field pattern of an MRI machine.
FIG. 19 is a diagram of another embodiment of a system includes one or more bio-medical units 10, a transmitter unit 126, and a receiver unit 128. Each of the bio-medical units 10 includes a power harvesting module 46, an EM transceiver 174, a processing module 50, and memory 52. The transmitter unit 126 includes a MRI transmitter 130 and electromagnetic (EM) modulator 170. The receiver unit 128 includes a MRI receiver 134 and an EM demodulator 172. The transmitter unit 126 and receiver unit 128 may be part of a portable MRI device, may be part of a full sized MRI machine, or part of a separate device for generating EM signals for powering the bio-medical unit 10.
In an example of operation, the MRI transmitter 130 generates an electromagnetic signal that is received by the EM modulator 170. The EM modulator 170 modulates a communication signal on the EM signal to produce an inbound modulated EM signal 176. The EM modulator 170 may modulate (e.g., amplitude modulation, frequency modulation, amplitude shift keying, frequency shift keying, etc.) the magnetic field and/or electric field of the EM signal. In another embodiment, the EM modulator 170 may modulate the magnetic fields produced by the gradient coils to produce the inbound modulated EM signals 176.
The bio-medical unit 10 recovers power from the modulated electromagnetic (EM) signals. In addition, the EM transceiver 174 demodulates the modulated EM signals 178 to recover the communication signal. For outbound signals, the EM transceiver 174 modulates an outbound communication signal to produce outbound modulated EM signals 180. In this instance, the EM transceiver 174 is generating an EM signal that, in air, is modulated on the EM signal transmitted by the transmitter unit 126. In one embodiment, the communication in this system is half duplex such that the modulation of the inbound and outbound communication signals is at the same frequency. In another embodiment, the modulation of the inbound and outbound communication signals are at different frequencies to enable full duplex communication.
FIG. 20 is a diagram of another example of a communication protocol within the system of FIG. 19. In this diagram, the MRI transmitter 20 transmits RF signals 152, which have a frequency in the range of 3-45 MHz, at various intervals with varying signal strengths. The power harvesting module 46 of the bio-medical units 10 may use these signals to generate power for the bio-medical unit 10.
In addition to the MRI transmitter 20 transmitting its signal, a constant magnetic field and various gradient magnetic fields are created 154-164 (one or more in the x dimension Gx, one or more in the y dimension Gy, and one or more in the z direction Gz). The power harvesting module 46 of the bio-medical unit 10 may further use the constant magnetic field and/or the varying magnetic fields 154-164 to create power for the bio-medical unit 10.
During the transmission periods of the cycle, the bio-medical unit 10 may communicate via the modulated EM signals 182. In this regard, the bio-medical unit 10 generates power and communicates in accordance with the conventional transmission-magnetic field pattern of an MRI machine.
FIG. 21 is a schematic block diagram of an embodiment of a micro MRI unit that includes one or more gradient coil bio-medical units 412 (three shown), a transmitting bio-medical unit 406, a receiving bio-medical unit 408. The micro MRI unit may further include one or more constant magnetic field generating bio-medical units 410. One or more of the bio-medical units 406, 408, 410, and 412 may be implanted within a host body and/or positioned on the skin of the host body.
In an example of operation, a constant magnetic field is applied to a particular part of a host body, which contains a body object of interest. The constant magnetic field is of strength to change the magnetic moments of the photons of some of the molecules of the body object (e.g., organ, tissue, blood, tendon, etc.) such that they align with the direction of the field. Note that one or more constant magnetic field bio-medical units 410 and/or an external source may generate the constant magnetic field. Further note that, as a photon's energy increases, it frequency increases correspondingly.
The transmitting bio-medical unit transmit a varying radio frequency (RF) signal in a direction of the body object. The varying RF signal has a frequency corresponding to the resonance frequency of the photons and is enabled for a short duration (e.g., less than a few seconds) to flip the spin of the aligned protons. The transmit power (e.g., the intensity) and the on duration of the RF signal is varied to varying the number of protons that flip their spin. For instance, the greater the intensity and/or duration, the spin of more aligned protons will flip. When the RF signal is turned off, the protons decay to their original spin-down state. The difference in energy between the two states is released as a photon, which provides the representation of the RF signal that the receiving bio-medical unit detects.
To control where the protons are excited, the one or more gradient magnetic field bio-medical units 412-1 through 412-3 generate one or more gradient magnetic fields in an area proximal to the body object. The gradient magnetic fields may be in one or more dimensions of a three-dimensional space. For instance, one of the gradient magnetic field bio-medical unit generates a gradient magnetic field along a first axis of a three-dimensional axis system (e.g., the x axis), a second gradient magnetic field bio-medical unit generates a second gradient magnetic field along a second axis of the three-dimensional axis system (e.g., a y axis), and a third gradient magnetic field bio-medical unit generates a third gradient magnetic field along a third axis of the three-dimensional axis system (e.g., a z axis).
The receiving bio-medical unit receives a representation of the varying RF signal (e.g., the energy difference as the protons decay to their original spin-down state). The receiving bio-medical unit then processes the representation of the varying RF signal to produce a processed signal. For example, the processing may be to packetize data representing the energy differences, where the packetized data constitutes the processed signal. As another example, a processing module of the receiving bio-medical unit generates image data based on the protons in the different tissues of the body object returning to their equilibrium state at different rates.
The receiving bio-medical unit then outputs the processed signal. For example, the receiving bio-medical unit may output the processed signal to an external communication unit 24 or to another bio-medical unit. In the latter case, the other bio-medical unit outputs the processed signal to the external communication device 24. The communication with the external communication unit 24 may be coordinated with the MRI signal sequencing as previously discussed.
FIG. 22 is a flowchart of an embodiment of a method for controlling power harvesting within a bio-medical unit 10. The method begins at step 418 wherein the processing module 50 of the bio-medical unit 10 initializes (e.g., when it is supplied power and wakes up) itself. For example, the processing module 50 executes an initialization boot sequence stored in the memory 52. The initialization boot sequence includes operational instructions that cause the processing module to initialize its registers to accept further instructions. The initialization boot sequence may further include operational instructions to initialize one or more of the communication module 48, the functional module(s) 54 initialized, etc.
The method continues at step 420 where the processing module 50 determines the state of the bio-medical unit (e.g., actively involved in a task, inactive, data gathering, performing a function, etc.). Such a determination may be based on one or more of previous state(s) (e.g., when the processing module was stopped prior to losing power), an input from the functional module 54, a list of steps or elements of a task, the current step of a MRI sequence, and/or new tasks received via the communication module 48.
The method continues at step 422 where the processing module 50 determines the bio-medical unit power level, which may be done by measuring the power harvesting module 46 output Vdd 56. Note that voltage is one proxy for the power level and that other proxies may be utilized including estimation of milliWatt-hours available, a time of operation before loss of operating power estimate, a number of CPU instructions estimate, a number of task elements, a number of tasks estimate, and/or another other estimator to assist in determining how much the bio-medical unit 10 can accomplish prior to losing power. Further note that the processing module 50 may save historic records of power utilization in the memory 52 to assist in subsequent determinations of the power level.
The method continues at step 424 where the processing module 50 compares the power level to the high threshold (e.g., a first available power level that allows for a certain level of processing). If yes, the method continues to step 426 where the processing module 50 enables the execution of H number of instructions. The processing module 50 may utilize a predetermined static value of the H instructions or a dynamic value that changes as a result of the historic records. For example, the historic records may indicate that there was an average of 20% more power capacity left over after the last ten times of instruction execution upon initialization. The processing module 50 may adjust the value of H upward such that the on-going left over power is less than 20% in order to more fully utilize the available power each time the bio-medical unit 10 has power.
The method continues at step 428 where the processing module 50 saves the state in the memory 52 upon completion of the execution of the H instructions such that the processing module 50 can start in a state in accordance with this state upon the next initialization. The method then continues at step 430 where the processing module 50 determines whether it will suspend operations based on one or more of a re-determined power level (e.g., power left after executing the instructions), a predetermined list, a task priority, a task state, a priority indicator, a command, a message, and/or a functional module input. If not, the method repeats at step 422. If yes, the method branches to step 440 where the processing module 50 suspends operations of the bio-medical unit.
If, at step 424, the power level is not greater than the high threshold, the method continues at step 432 where the processing module 50 determines whether the power level compares favorably to a low threshold. If not, the method continues a step 440 where the processing module 50 suspends operations of the bio-medical unit.
If the comparison at step 432 was favorable, the method continues at step 434 where the processing module 50 executes L instructions. The processing module 50 may utilize a predetermined static value of the L instructions or a dynamic value that changes as a result of the historic records as discussed previously. For example, the historic records may indicate that there was an average of 10% more power capacity left over after the last ten times of instruction execution upon initialization. The processing module 50 may adjust the value of L downward such that the on-going left over power is less than 10% in order to more fully utilize the available power each time the bio-medical unit 10 has power.
The method continues at step 436 where the processing module 50 saves the state in the memory 52 upon completion of the execution of the L instructions such that the processing module 50 can start in a state in accordance with this state upon the next initialization. The method then continues at step 438 where the processing module 50 determines whether it will suspend operations based on one or more of a re-determined power level (e.g., power left after executing the instructions), a predetermined list, a task priority, a task state, a priority indicator, a command, a message, and/or a functional module input. If yes, the method branches to step 440. If not, the method repeats at step 422.
FIG. 23 is a flowchart illustrating MMW communications within a MRI sequence where the processing module 50 determines MMW communications in accordance with an MRI sequence. The method begins at step 442 where the processing module 50 determines whether the MRI is active based on receiving MRI EM signals. At step 444, the method branches to step 446 or step 448. When the MRI is active, the method continues at step 446 where the processing module 50 performs MMW communications as previously discussed.
The method continues at step 448 where the processing module 50 determines the MRI sequence based on received MRI EM signals (e.g., gradient pulses and/or MRI RF pulses as shown in one or more of the preceding figures). The method continues at step 450 where the processing module 50 determines whether it is time to perform receive MMW communication in accordance with the MRI sequence. For example, the MMW transceiver 138 may receive MMW inbound signals 148 between any of the MRI sequence steps. As another example, the MMW transceiver 138 may receive MMW inbound signals 148 between specific predetermined steps of the MRI sequence.
At step 452 the method branches back to step 450 or to step 454. When it is time to receive, the method continues at step 454 where the processing module 50 coordinates the MMW transceiver 138 receiving the MMW inbound signals, which may include one or more of a status request, a records request, a sensor data request, a processed data request, a position request, a command, and/or a request for MRI echo signal data. The method then continues at step 456 where the processing module 50 determines whether there is at least one message pending to transmit (e.g., in a transmit queue). At step 458 the method branches back to step 442 or to step 460.
At step 460, the processing module 50 determines when it is time to transmit a MMW communication in accordance with the MRI sequence. For example, the MMW transceiver 138 may transmit MMW outbound signals 150 between any of the MRI sequence steps. As another example, the MMW transceiver 138 may transmit MMW outbound signals 150 between specific predetermined steps of the MRI sequence.
At step 462, the method branches to back step 456 or to step 464. The method continues at step 464 where the processing module 50 coordinates the MMW transceiver 138 transmitting the MMW outbound signals 150, which may include one or more of a status request response, a records request response, a sensor data request response, a processed data request response, a position request response, a command response, and/or a request for MRI echo signal data response. The method then branches back to step 442.
FIG. 24 is a flowchart illustrating the processing of MRI signals where the processing module 50 of the bio-medical unit 10 may assist the MRI in the reception and processing of MRI EM signals 146. The method begins at step 466 where the processing module 50 determines if the MRI is active based on receiving MRI EM signals 146. The method branches back to step 466 when the processing module 50 determines that the MRI is not active. For example, the MRI sequence may not start until the processing module 50 communicates to the MRI unit that it is available to assist. The method continues to step 470 when the processing module 50 determines that the MRI is active.
At step 470, the processing module 50 determines the MRI sequence based on received MRI EM signals 146 (e.g., gradient pulses and/or MRI RF pulses). At step 472, the processing module receives EM signals 146 and/or MMW communication 532 in accordance with the MRI sequence and decodes a message. For example, the MMW transceiver 138 may receive MMW inbound signals 148 between any of the MRI sequence steps. As another example, the MMW transceiver 138 may receive MMW inbound signals 148 between specific predetermined steps of the MRI sequence. In yet another example, the processing module 50 may receive EM signals 146 at any point of the MRI sequence such that the EM signals 146 contain a message for the processing module 50.
At step 474, the processing module 50 determines whether to assist in the MRI sequence based in part on the decoded message. The determination may be based on a comparison of the assist request to the capabilities of the bio-medical unit 10. At step 476, the method branches to step 480 when the processing module 50 determines to assist in the MRI sequence. The method continues at step 478 where the processing module 50 performs other instructions contained in the message and the method ends.
At step 480, the processing module 50 begins the assist steps by receiving echo signals 530 during the MRI sequence. Note the echo signals 530 may comprise EM RF signals across a wide frequency band as reflected off of tissue during the MRI sequence. At step 482, the processing module 50 processes the received echo signals 530 to produce processed echo signals. Note that this may be a portion of the overall processing required to lead to the desired MRI imaging.
At step 484, the processing module 50 determines the assist type based on the decoded message from the MRI unit. The assist type may be at least passive or active where the passive type collects echo signal 530 information and sends it to the MRI unit via MMW outbound signals 150 and the active type collects echo signal information and re-generates a form of the echo signals 530 and sends the re-generated echo signals to the MRI unit via outbound modulated EM signals (e.g., the MRI unit interprets the re-generated echo signals as echo signals to improve the overall system gain and sensitivity).
The method branches to step 494 when the processing module 50 determines the assist type to be active. The method continues to step 486 when the processing module 50 determines the assist type to be passive. At step 486, the processing module 50 creates an echo message based on the processed echo signals where the echo message contains information about the echo signals 530.
At step 488, the processing module 50 determines when it is time to transmit the echo message encoded as MMW outbound signals 150 via MMW communication in accordance with the MRI sequence. For example, the MMW transceiver 138 may transmit MMW outbound signals 150 between any of the MRI sequence steps. In another example, the MMW transceiver 138 may transmit MMW outbound signals 150 between specific predetermined steps of the MRI sequence.
At step 490, the method branches back to step 488 when the processing module 50 determines that it is not time to transmit the echo message. At step 490, the method continues to step 492 where the processing module 50 transmits the echo message encoded as MMW outbound signals 150.
At step 494, the processing module 50 creates echo signals based on the processed echo signals. At step 496, the processing module 50 determines when it is time to transmit the echo signals as outbound modulated EM signals 180 in accordance with the MRI sequence. At step 498, the method branches back to step 496 when the processing module 50 determines that it is not time to transmit the echo signals. At step 498, the method continues to step 500 where the processing module 50 transmits the echo signals encoded as outbound modulated EM signals 180. Note that the transmitted echo signals emulate the received echo signals 530 with improvements to overcome low MRI power levels and/or low MRI receiver sensitivity.
FIG. 25 is a flowchart illustrating communication utilizing MRI signals where the processing module 50 determines MMW signaling in accordance with an MRI sequence. The method begins at step 502 where the processing module 50 determines if the MRI is active based on receiving MRI EM signals 146. At step 504, the method branches to step 508 when the processing module 50 determines that the MRI is active. At step 504, the method continues to step 506 when the processing module 50 determines that the MRI is not active. At step 506, the processing module 50 queues pending transmit messages. The method branches to step 502.
At step 508, the processing module 50 determines the MRI sequence based on received MRI EM signals 146 (e.g., gradient pulses and/or MRI RF pulses). At step 510, the processing module 50 determines when it is time to perform receive communication in accordance with the MRI sequence. For example, the EM transceiver 174 may receive inbound modulated EM signals 146 containing message information from any of the MRI sequence steps.
At step 512, the method branches back to step 510 when the processing module 50 determines that it is not time to perform receive communication. At step 512, the method continues to step 514 where the processing module 50 directs the EM transceiver 174 to receive the inbound modulated EM signals. The processing module 50 may decode messages from the inbound modulated EM signals 146 such that the messages include one or more of a echo signal collection assist request, a status request, a records request, a sensor data request, a processed data request, a position request, a command, and/or a request for MRI echo signal data. Note that the message may be decoded from the inbound modulated EM signals 146 in one or more ways including detection of the ordering of the magnetic gradient pulses, counting the number of gradient pulses, the slice pulse orderings, detecting small differences in the timing of the pulses, and/or demodulation of the MRI RF pulse.
At step 516 the processing module 50 determines if there is at least one message pending to transmit (e.g., in a transmit queue). At step 518, the method branches back to step 502 when the processing module 50 determines that there is not at least one message pending to transmit. At step 518, the method continues to step 520 where the processing module 50 determines when it is time to perform transmit communication in accordance with the MRI sequence. For example, the EM transceiver 174 may transmit outbound modulated EM signals 180 between any of the MRI sequence steps. In another example, the EM transceiver 174 may transmit the outbound modulated EM signals 180 between specific predetermined steps of the MRI sequence. In yet another example, the EM transceiver 174 may transmit the outbound modulated EM signals 180 in parallel with specific predetermined steps of the MRI sequence, but may utilize a different set of frequencies unique to the EM transceiver 174.
At step 522, the method branches back to step 520 when the processing module 50 determines that it is not time to perform transmit communication. At step 522, the method continues to step 524 where the processing module 50 directs the EM transceiver 174 to prepare the outbound modulated EM signals 180 based on the at least one message pending to transmit. The processing module 50 may encode messages into the outbound modulated EM signals 180 such that the messages include one or more of a status request response, a records request response, a sensor data request response, a processed data request response, a position request response, a command response, and/or a request for MRI echo signal data response. The method branches back to step 502.
FIG. 26 is a schematic block diagram of a micro MRI unit that includes one or more transmitting bio-medical units 406, one or more receiving bio-medical units 408, and one or more gradient bio-medical units 412. The transmitting bio-medical unit 406 includes a power harvesting module 46, a processing module 50, a communication module 48, a transmission module 550, a beamforming module 552, and an antenna array 554. The receiving bio-medical unit 408 includes a power harvesting module 46, a processing module 50, a communication module 48, a reception module 556, a beamforming module 560, and an antenna array 558. The gradient bio-medical unit 412 includes a power harvesting module 46 and at least one adjustable coil 562. The gradient bio-medical unit 412 may further include a processing module 50 and/or a communication module 48.
In an example of operation, the transmitting bio-medical unit 406, the receiving bio-medical unit 408, and the gradient bio-medical unit 412 are positioned (in vivo and/or on the body) of a host body proximal to a body object 268. A constant magnetic field is applied in the area proximal to the body object 268 by an external constant magnetic source and/or a constant magnetic field bio-medical unit (not shown in this figure).
With a constant magnetic field applied, the one or more gradient magnetic field bio-medical units 412-1 through 412-3 generate one or more gradient magnetic fields in an area proximal to the body object by providing a varying current to the adjustable coil 562 (e.g., an inductor). The gradient magnetic fields may be in one or more dimensions of a three-dimensional space. For instance, one of the gradient magnetic field bio-medical unit generates a gradient magnetic field along a first axis of a three-dimensional axis system (e.g., the x axis), a second gradient magnetic field bio-medical unit generates a second gradient magnetic field along a second axis of the three-dimensional axis system (e.g., a y axis), and a third gradient magnetic field bio-medical unit generates a third gradient magnetic field along a third axis of the three-dimensional axis system (e.g., a z axis).
With the constant and gradient magnetic fields, the transmission module 550 of the transmitting bio-medical unit 406 generates a plurality of RF signals. For example, the transmission module 550 includes a plurality of up-conversion modules that mix a reference signal with a local oscillation to produce the RF signals to have a frequency that corresponds to a resonance frequency of the photons. In addition, the transmission module 550 generates the RF signals at a particular power intensity and for a particular duration.
The beamforming module 552 generates a plurality of phase angles to provide beamforming of the RF signals. In this instance, the antenna array 554 (e.g., two or more antennas) transmits the plurality of RF signals in accordance with the plurality of phase angles to produce the varying RF signal in the direction of the body object. For example, the RF signals are combined in air in accordance with the phase angles to beamform the varying RF signal at the body object 268.
The antenna array 558 receives the varying RF signal in accordance with a plurality of phase angles to produce a plurality of received RF signals. The beamforming module 560 generate the plurality of phase angles, which correspond to the phase angles generated by the beamforming module 552 of the transmitting bio-medical unit and may account for the channel response between the two bio-medical units 406 and 408.
The reception module receives the plurality of RF signals and converts them into a baseband or near-baseband signal (e.g., an intermediate frequency of 0 to a few Mega-Hertz). The communication module outputs the baseband or near-baseband signal as the processed signal. Note that the processing module 50 may further process the baseband or near-baseband signal to render MRI image data, which is subsequently transmitted by the communication module 48 to an external communication unit 24 or to another bio-medical unit.
As may be used herein, the terms “substantially” and “approximately” provides an industry-accepted tolerance for its corresponding term and/or relativity between items. Such an industry-accepted tolerance ranges from less than one percent to fifty percent and corresponds to, but is not limited to, component values, integrated circuit process variations, temperature variations, rise and fall times, and/or thermal noise. Such relativity between items ranges from a difference of a few percent to magnitude differences. As may also be used herein, the term(s) “coupled to” and/or “coupling” and/or includes direct coupling between items and/or indirect coupling between items via an intervening item (e.g., an item includes, but is not limited to, a component, an element, a circuit, and/or a module) where, for indirect coupling, the intervening item does not modify the information of a signal but may adjust its current level, voltage level, and/or power level. As may further be used herein, inferred coupling (i.e., where one element is coupled to another element by inference) includes direct and indirect coupling between two items in the same manner as “coupled to”. As may even further be used herein, the term “operable to” indicates that an item includes one or more of power connections, input(s), output(s), etc., to perform one or more its corresponding functions and may further include inferred coupling to one or more other items. As may still further be used herein, the term “associated with”, includes direct and/or indirect coupling of separate items and/or one item being embedded within another item. As may be used herein, the term “compares favorably”, indicates that a comparison between two or more items, signals, etc., provides a desired relationship. For example, when the desired relationship is that signal 1 has a greater magnitude than signal 2, a favorable comparison may be achieved when the magnitude of signal 1 is greater than that of signal 2 or when the magnitude of signal 2 is less than that of signal 1.
The present invention has also been described above with the aid of method steps illustrating the performance of specified functions and relationships thereof. The boundaries and sequence of these functional building blocks and method steps have been arbitrarily defined herein for convenience of description. Alternate boundaries and sequences can be defined so long as the specified functions and relationships are appropriately performed. Any such alternate boundaries or sequences are thus within the scope and spirit of the claimed invention.
The present invention has been described above with the aid of functional building blocks illustrating the performance of certain significant functions. The boundaries of these functional building blocks have been arbitrarily defined for convenience of description. Alternate boundaries could be defined as long as the certain significant functions are appropriately performed. Similarly, flow diagram blocks may also have been arbitrarily defined herein to illustrate certain significant functionality. To the extent used, the flow diagram block boundaries and sequence could have been defined otherwise and still perform the certain significant functionality. Such alternate definitions of both functional building blocks and flow diagram blocks and sequences are thus within the scope and spirit of the claimed invention. One of average skill in the art will also recognize that the functional building blocks, and other illustrative blocks, modules and components herein, can be implemented as illustrated or by discrete components, application specific integrated circuits, processors executing appropriate software and the like or any combination thereof.

Claims

1. A micro magnetic resonance imaging (MRI) unit comprises:

a gradient magnetic field bio-medical unit operable to generate a gradient magnetic field in a proximal area of a body object within a host body, wherein a constant magnetic field is present in the proximal area of the body object;

a transmitting bio-medical unit operable to transmit a varying radio frequency (RF) signal in a direction of the body object; and

a receiving bio-medical unit operable to:

receive a representation of the varying RF signal;

process the representation of the varying RF signal to produce a processed signal; and

output the processed signal, wherein at least one of the gradient magnetic field bio-medical unit, the transmitting bio-medical unit, and the receiving bio-medical unit is implanted in a host body.

2. The micro MRI unit of claim 1, wherein the transmitting bio-medical unit comprises:

a transmission module operable to generate a plurality of RF signals, wherein an RF signal of the plurality of RF signals has a frequency corresponding to a resonance frequency, has a particular power intensity, and is transmitted for a particular duration;

a beamforming module operable to generate a plurality of phase angles; and

an antenna array operable to transmit the plurality of RF signals in accordance with the plurality of phase angles to produce the varying RF signal in the direction of the body object.

3. The micro MRI unit of claim 1, wherein the receiving bio-medical unit comprises:

an antenna array operable to receive the varying RF signal in accordance with a plurality of phase angles to produce a plurality of received RF signals;

a beamforming module operable to generate the plurality of phase angles;

a reception module operable to:

receive the plurality of RF signals, wherein an RF signal of the plurality of RF signals has a frequency corresponding to a resonance frequency, has a particular power intensity, and is transmitted for a particular duration; and

convert the plurality of RF signals into a baseband or near-baseband signal; and

a communication module operable to output the baseband or near-baseband signal as the processed signal.

4. The micro MRI unit of claim 3 further comprises:

the reception module further operable to convert the baseband or near-baseband signal into MRI image data; and

the communication module further operable to output the MRI image data as the processed signal.

5. The micro MRI unit of claim 1 further comprises:

a constant magnetic field bio-medical unit operable to generate the constant magnetic field.

6. The micro MRI unit of claim 1, wherein each of the gradient magnetic field bio-medical unit, the transmitting bio-medical unit, and the receiving bio-medical unit further comprises:

a radio frequency or millimeter wave communication unit for communication with an external communication device.

7. The micro MRI unit of claim 1, wherein the gradient magnetic field bio-medical unit comprises:

an adjustable coil operable to generate the varying magnetic field based on an adjustable magnetic field signal.

8. The micro MRI unit of claim 1 further comprises:

a second gradient magnetic field bio-medical unit; and

a third gradient magnetic field bio-medical unit, wherein the gradient magnetic field bio-medical unit generates the gradient magnetic field along a first axis of a three-dimensional axis system, the second gradient magnetic field bio-medical unit generates a second gradient magnetic field along a second axis of the three-dimensional axis system, and the third gradient magnetic field bio-medical unit generates a third gradient magnetic field along a third axis of the three-dimensional axis system.

9. The micro MRI unit of claim 1, wherein each of the gradient magnetic field bio-medical unit, the transmitting bio-medical unit, and the receiving bio-medical unit further comprises:

a near field communication unit for at least one of communication with an external communication device and communication between the gradient magnetic field bio-medical unit, the transmitting bio-medical unit, and the receiving bio-medical unit.

10. The micro MRI unit of claim 1, wherein each of the gradient magnetic field bio-medical unit, the transmitting bio-medical unit, and the receiving bio-medical unit further comprises:

a power harvesting module operable to generate a supply voltage from an electromagnetic signal, wherein the supply voltage powers respective components of the gradient magnetic field bio-medical unit, the transmitting bio-medical unit, and the receiving bio-medical unit.

11. A micro magnetic resonance imaging (MRI) unit comprises:

a transmitting bio-medical unit operable to transmit a varying radio frequency (RF) signal in a direction of a body object within a host body, wherein a gradient magnetic field and a constant magnetic field are present in the proximal area of the body object; and

a receiving bio-medical unit operable to:

receive a representation of the varying RF signal;

12. The micro MRI unit of claim 11, wherein the transmitting bio-medical unit comprises:

a beamforming module operable to generate a plurality of phase angles; and

13. The micro MRI unit of claim 11, wherein the receiving bio-medical unit comprises:

a beamforming module operable to generate the plurality of phase angles;

a reception module operable to:

14. The micro MRI unit of claim 13 further comprises:

15. The micro MRI unit of claim 11 further comprises:

16. The micro MRI unit of claim 11, wherein each of the transmitting bio-medical unit and the receiving bio-medical unit further comprises:

17. The micro MRI unit of claim 11 further comprises:

a first gradient magnetic field bio-medical unit;

a second gradient magnetic field bio-medical unit; and

a third gradient magnetic field bio-medical unit, wherein the first gradient magnetic field bio-medical unit generates a first gradient magnetic field along a first axis of a three-dimensional axis system, the second gradient magnetic field bio-medical unit generates a second gradient magnetic field along a second axis of the three-dimensional axis system, and the third gradient magnetic field bio-medical unit generates a third gradient magnetic field along a third axis of the three-dimensional axis system.

18. The micro MRI unit of claim 11, wherein each of the transmitting bio-medical unit and the receiving bio-medical unit further comprises:

a near field communication unit for at least one of communication with an external communication device and communication between the transmitting bio-medical unit and the receiving bio-medical unit.

19. The micro MRI unit of claim 11, wherein each of the transmitting bio-medical unit and the receiving bio-medical unit further comprises:

a power harvesting module operable to generate a supply voltage from an electromagnetic signal, wherein the supply voltage powers respective components of the transmitting bio-medical unit and the receiving bio-medical unit.