Embedded bio-sensor system

• US 7,297,112 B2
• Filed: 10/18/2006
• Issued: 11/20/2007
• Est. Priority Date: 05/20/2004
• Status: Expired due to Fees

• Current Assignee: Magna Equities I, LLC
• Original Assignee: Digital Angel Corporation
• Inventors: Li, William, Pang, Dexing, Zhou, Peter
• Primary Examiner(s): Marmori, II; Charles A.
• Assistant Examiner(s): Mallari; Patricia C
• Application Number:
  US11/582,790
• Publication Number:
  US 20070038054A1
• Time in Patent Office: 398 Days
• Field of Search: None
• US Class Current: 600/300
• CPC Class Codes: A61B 2562/08 Sensors provided with means for identification, e.g. barcodes or memory chips
• CPC Class Codes: A61B 5/0031 Implanted circuitry
• CPC Class Codes: A61B 5/14532 for measuring glucose, e.g. by tissue impedance measurement
• CPC Class Codes: A61B 5/14865 invasive, e.g. introduced into the body by a catheter or needle or using implanted sensors
• CPC Class Codes: G16H 40/67 for remote operation

Abstract

Provided is a bio-sensor system which utilizes radio frequency identification technology and which includes a remote transponder in wireless communication with an implantable passively-powered on-chip transponder. The bio-sensor system is specifically adapted to provide a substantially stable and precise sensor reference voltage to a sensor assembly that is included with the on-chip transponder. The remote transponder is also configured to remotely receive data representative of a physiological parameter of the patient as well as identification data and may enable readout of one or more of the physiological parameters that are measured, processed and transmitted by the on-chip transponder upon request by the remote transponder. The precision and stability of the sensor reference voltage is enhanced by the specific circuit architecture of the glucose sensor to allow for relatively accurate measurement of the physiological parameter such as measurement of glucose concentration by a glucose sensor without the use of a microprocessor.

Claims

1. A bio-sensor system adapted to provide a substantially stable voltage to a sensor assembly that is implantable in a patient such that physiological parameters thereof may be accurately measured, the bio-sensor system comprising:

a remote transponder configured to transmit a scanner signal to an implantable on-chip transponder to receive a data signal therefrom;

the implantable on-chip transponder in wireless communication with the remote transponder and being configured to receive the scanner signal and transmit the data signal, the on-chip transponder including;

a sensor being configured to generate a sensor signal representative of the physiological parameter of the patient;

a radio frequency (RF) receiver configured to receive the scanner signal from the remote transponder and to filter, amplify and demodulate the scanner signal and generate a message signal for controlling the on-chip transponder;

a power receiver configured to receive the scanner signal from the remote transponder and to generate a power signal for powering the on-chip transponder;

an analog-to-digital (A/D) assembly connected to the power receiver, the RF receiver and the sensor, the A/D assembly being configured to respectively receive the power signal, the sensor signal and the message signal and generate a digital signal in response thereto;

a data processor connected to the A/D assembly, the power receiver and the RF receiver, the data processor being configured to respectively receive the power signal, the digital signal and the message signal and generate a data signal in response thereto; and

an RF transmitter connected to the power receiver, the data processor and the RF receiver and being configured to respectively receive the power signal, the data signal and the message signal and to modulate, amplify, filter and transmit the data signal;

wherein the power receiver is configured to supply a substantially non-deviating sensor reference voltage to the sensor for accurate measurement of the physiological parameter, the remote transponder being configured to receive the data signal from the RF transmitter and to extract data representative of the physiological parameter;

wherein the A/D assembly includes;

a processor-filter connected to the bio-sensor and being configured to receive the sensor signal therefrom and generate a filtered signal in response thereto;

an amplifier connected to the processor-filter and being configured to receive the filtered signal therefrom and generate an amplified signal in response thereto;

a voltage comparator connected to the power receiver and being configured to receive the power signal therefrom and generate a normalized voltage signal in response thereto;

an A/D converter connected to the amplifier and the voltage comparator and being configured to receive respective ones of the amplified signal and the normalized voltage signal therefrom and generate a converter signal in response thereto;

a covert logic device connected to the A/D converter and being configured to receive the converter signal therefrom and generate a logic signal in response thereto; and

a controller in two-way communication with the RF receiver and being connected to the covert logic device, the controller being configured to receive the message signal and the logic signal and to synchronize the A/D converter with the data processor for subsequent generation of the digital signal in response to the message signal and the logic signal.

2. The bio-sensor system of claim 1 further including:

a plurality of sensors, each one of the sensors being operative to sense a distinct physiological parameter of the patient and generate a sensor signal representative thereof;

wherein the A/D assembly further includes a switch connected to the controller with the controller being responsive to the message signal and being operative to cause the switch to select among sensor signals for subsequent transmission thereof to the processor filter.

3. The bio-sensor system of claim 2 wherein the data processor includes:

a signal filter connected to the A/D assembly and being configured to receive the digitized signal therefrom, remove unwanted noise and generate a filtered signal in response thereto;

an amplifier connected to the signal filter and being configured to receive the filtered signal and generate an amplified signal in response thereto;

a program counter connected to the RF receiver and the power receiver and being configured to receive respective ones of the message signal and the power signal therefrom and generate a gated signal in response thereto;

an interrupt request device connected to the program counter and being configured to receive the gated signal therefrom and generate an interrupt request signal in response thereto;

a calculator connected to the signal filter, the amplifier and the interrupt request device and being configured to receive respective ones of the filtered signal, the amplified signal and the gated signal therefrom and generate an encoded signal in response thereto; and

a digital filter connected to the calculator and being configured to receive the encoded signal therefrom and generate the data signal in response thereto.

4. A bio-sensor system adapted to provide a substantially stable voltage to a sensor assembly that is implantable in a patient such that physiological parameters thereof may be accurately measured, the bio-sensor system comprising:

a remote transponder configured to transmit a scanner signal to an implantable on-chip transponder to receive a data signal therefrom;

the implantable on-chip transponder in wireless communication with the remote transponder and being configured to receive the scanner signal and transmit the data signal, the on-chip transponder including;

a sensor being configured to generate a sensor signal representative of the physiological parameter of the patient;

a radio frequency (RF) receiver configured to receive the scanner signal from the remote transponder and to filter, amplify and demodulate the scanner signal and generate a message signal for controlling the on-chip transponder;

a power receiver configured to receive the scanner signal from the remote transponder and to generate a power signal for powering the on-chip transponder;

an analog-to-digital (A/D) assembly connected to the power receiver, the RF receiver and the sensor, the A/D assembly being configured to respectively receive the power signal, the sensor signal and the message signal and generate a digital signal in response thereto;

a data processor connected to the A/D assembly, the power receiver and the RF receiver, the data processor being configured to respectively receive the power signal, the digital signal and the message signal and generate a data signal in response thereto; and

an RF transmitter connected to the power receiver, the data processor and the RF receiver and being configured to respectively receive the power signal, the data signal and the message signal and to modulate, amplify, filter and transmit the data signal;

wherein the power receiver is configured to supply a substantially non-deviating sensor reference voltage to the sensor for accurate measurement of the physiological parameter, the remote transponder being configured to receive the data signal from the RF transmitter and to extract data representative of the physiological parameter;

wherein the RF transmitter includes;

a data input filter connected to the data processor and being configured to receive the data signal therefrom to filter out high-frequency spectral components and generate a filtered data signal in response thereto;

a modulator connected to the power receiver, the RF receiver and the data input filter and being configured to receive respective ones of the message signal, the power signal and the filtered data signal therefrom and to pulse code modulate the filtered data signal by varying amplitude thereof and generating a first and second modulated signal in response thereto;

a first transmitter amplifier connected to the modulator and being configured to receive the first modulated signal therefrom;

a transmitter filter cooperating with the first transmitter amplifier to create a first amplified signal at a desired frequency of radio transmission;

a second transmitter amplifier connected to the modulator and the first transmitter and being configured to receive respective ones of the second modulated signal and the first amplified signal therefrom and generate a second amplified signal having a desired power level for transmission to the remote transponder;

a surface acoustic wave (SAW) filter connected to the second transmitter amplifier and being configured to receive the second amplified signal and remove unwanted harmonics therefrom and generate a transmitted signal in response thereto; and

a RF transmitter antenna connected to the SAW filter and being configured to radiate the transmitted signal for receipt by the receiving antenna of the remote transponder.

5. A bio-sensor system adapted to provide a substantially stable voltage to a sensor assembly that is implantable in a patient such that physiological parameters thereof may be accurately measured, the bio-sensor system comprising:

a remote transponder configured to transmit a scanner signal to an implantable on-chip transponder to receive a data signal therefrom;

the implantable on-chip transponder in wireless communication with the remote transponder and being configured to receive the scanner signal and transmit the data signal, the on-chip transponder including;

a sensor being configured to generate a sensor signal representative of the physiological parameter of the patient;

a radio frequency (RF) receiver configured to receive the scanner signal from the remote transponder and to filter, amplify and demodulate the scanner signal and generate a message signal for controlling the on-chip transponder;

a power receiver configured to receive the scanner signal from the remote transponder and to generate a power signal for powering the on-chip transponder;

an analog-to-digital (A/D) assembly connected to the power receiver, the RF receiver and the sensor, the A/D assembly being configured to respectively receive the power signal, the sensor signal and the message signal and generate a digital signal in response thereto;

a data processor connected to the A/D assembly, the power receiver and the RF receiver, the data processor being configured to respectively receive the power signal, the digital signal and the message signal and generate a data signal in response thereto; and

an RF transmitter connected to the power receiver, the data processor and the RF receiver and being configured to respectively receive the power signal, the data signal and the message signal and to modulate, amplify, filter and transmit the data signal;

wherein the power receiver is configured to supply a substantially non-deviating sensor reference voltage to the sensor for accurate measurement of the physiological parameter, the remote transponder being configured to receive the data signal from the RF transmitter and to extract data representative of the physiological parameter;

wherein the power receiver includes;

a syntonic oscillator connected to the RF receiver antenna and being configured to receive the scanner signal therefrom and generate an alternating current (AC) voltage signal in response thereto;

a rectifier connected to the syntonic oscillator and being configured to receive the AC voltage signal therefrom and generate a generally coarse direct current (DC) voltage signal in response thereto;

a filter connected to the rectifier and being configured to receive the direct voltage signal therefrom, the filter having a capacitor configured to store energy from cycles of the generally coarse DC voltage signal for release as a substantially smooth DC voltage signal;

a first regulator connected to the filter and being configured to receive the DC voltage signal therefrom and generate a first voltage signal to power the A/D assembly, the data processor and the RF transmitter;

a second regulator connected to the filter and being configured to receive the DC voltage signal therefrom and generate a second voltage signal to power the A/D assembly, the data processor and the RF transmitter; and

a sensor reference supply connected to the filter and being configured to receive the DC voltage signal therefrom and generate a sensor reference voltage signal to power the sensor assembly.

6. A bio-sensor system adapted to provide a substantially stable voltage to a sensor assembly that is implantable in a patient such that physiological parameters thereof may be accurately measured, the bio-sensor system comprising:

a remote transponder configured to transmit a scanner signal to an implantable on-chip transponder to receive a data signal therefrom;

the implantable on-chip transponder in wireless communication with the remote transponder and being configured to receive the scanner signal and transmit the data signal, the on-chip transponder including;

a sensor being configured to generate a sensor signal representative of the physiological parameter of the patient;

a radio frequency (RF) receiver configured to receive the scanner signal from the remote transponder and to filter, amplify and demodulate the scanner signal and generate a message signal for controlling the on-chip transponder;

a power receiver configured to receive the scanner signal from the remote transponder and to generate a power signal for powering the on-chip transponder;

an analog-to-digital (A/D) assembly connected to the power receiver, the RF receiver and the sensor, the A/D assembly being configured to respectively receive the power signal, the sensor signal and the message signal and generate a digital signal in response thereto;

a data processor connected to the A/D assembly, the power receiver and the RF receiver, the data processor being configured to respectively receive the power signal, the digital signal and the message signal and generate a data signal in response thereto; and

an RF transmitter connected to the power receiver, the data processor and the RF receiver and being configured to respectively receive the power signal, the data signal and the message signal and to modulate, amplify, filter and transmit the data signal;

wherein the power receiver is configured to supply a substantially non-deviating sensor reference voltage to the sensor for accurate measurement of the physiological parameter, the remote transponder being configured to receive the data signal from the RF transmitter and to extract data representative of the physiological parameter;

wherein the RF receiver includes;

an RF receiver antenna configured to receive the scanner signal from the remote transponder;

a surface acoustic wave (SAW) filter connected to the RF receiver antenna and being configured to receive the scanner signal therefrom and filter the scanner signal of unwanted signals and generate a filtered scanner signal in response thereto;

a first RF amplifier connected to the SAW filter and being configured to receive the filtered scanner signal therefrom and generate a first amplified scanner signal in response thereto;

a SAW delay connected to the first RF amplifier and configured to receive the first amplified scanner signal therefrom and generate a compared signal;

a second RF amplifier connected to the SAW delay and being configured to receive the compared signal therefrom;

a pulse generator connected in parallel to the SAW delay at the first and second RF amplifiers and cooperating therewith to generate first and second pulse signals for receipt by respective ones of the first and second RF amplifiers such that the second RF amplifier generates a second amplified RF signal; and

a detector-filter connected to the second RF amplifier and being configured to receive the second amplified RF signal therefrom and generate the message signal.

7. A bio-sensor system adapted to provide a substantially stable voltage to a sensor assembly that is implantable in a patient such that physiological parameters thereof may be accurately measured, the bio-sensor system comprising:

a remote transponder configured to transmit a scanner signal to an implantable on-chip transponder to receive a data signal therefrom;

the implantable on-chip transponder in wireless communication with the remote transponder and being configured to receive the scanner signal and transmit the data signal, the on-chip transponder including;

a sensor being configured to generate a sensor signal representative of the physiological parameter of the patient;

a radio frequency (RF) receiver configured to receive the scanner signal from the remote transponder and to filter, amplify and demodulate the scanner signal and generate a message signal for controlling the on-chip transponder;

a power receiver configured to receive the scanner signal from the remote transponder and to generate a power signal for powering the on-chip transponder;

an analog-to-digital (A/D) assembly connected to the power receiver, the RF receiver and the sensor, the A/D assembly being configured to respectively receive the power signal, the sensor signal and the message signal and generate a digital signal in response thereto;

a data processor connected to the A/D assembly, the power receiver and the RF receiver, the data processor being configured to respectively receive the power signal, the digital signal and the message signal and generate a data signal in response thereto; and

an RF transmitter connected to the power receiver, the data processor and the RF receiver and being configured to respectively receive the power signal, the data signal and the message signal and to modulate, amplify, filter and transmit the data signal;

wherein the power receiver is configured to supply a substantially non-deviating sensor reference voltage to the sensor for accurate measurement of the physiological parameter, the remote transponder being configured to receive the data signal from the RF transmitter and to extract data representative of the physiological parameter;

wherein the remote transponder includes;

an oscillator configured to generate an analog signal at a predetermined frequency;

an encoder connected to the oscillator and configured to receive and modulate the analog signal and generate an encoded signal in response thereto;

a power transmitter connected to the encoder and configured to receive and amplify the encoded signal and generate the scanner signal; and

a transmitting antenna connected to the power transmitter and configured to receive the scanner signal therefrom for radio transmission to the on-chip transponder;

wherein the remote transponder further includes;

a receiving antenna configured to receive the data signal from the RF transmitter;

a surface acoustic wave (SAW) filter connected to the receiving antenna and being configured to receive and filter the data signal of unwanted signals that may interfere with the remote transponder and generate a filtered data signal in response thereto;

a first RF amplifier connected to the SAW filter and being configured to receive the filtered data signal therefrom and generate a first amplified data signal in response thereto;

a SAW delay connected to the first RF amplifier and configured to receive the first amplified data signal therefrom and generate a compared signal;

a second RF amplifier connected to the SAW delay and being configured to receive the compared signal therefrom;

a pulse generator connected in parallel to the SAW delay at the first and second RF amplifiers and cooperating therewith to generate first and second pulse signals for receipt by respective ones of the first and second RF amplifiers such that the second RF amplifier generates a second amplified RF signal; and

a detector-filter connected to the second RF amplifier and being configured to receive the second amplified RF signal for extraction of digitized data therefrom.

8. The bio-sensor system of claim 7 further including a decoder connected to the detector-filter and being configured to receive the second amplified RF signal for extraction of digitized data therefrom.