Range gated radio frequency physiology sensor

• US 9,445,729 B2
• Filed: 07/18/2013
• Issued: 09/20/2016
• Est. Priority Date: 07/20/2012
• Status: Active Grant

• Current Assignee: ResMed Sensor Technologies Limited (ResMed Incorporated)
• Original Assignee: ResMed Sensor Technologies Limited (ResMed Incorporated)
• Inventors: McMahon, Stephen, Wren, Michael, Wood, Spencer Terry, Conway, Kieran, Heneghan, Conor
• Primary Examiner(s): Cattungal, Sanjay
• Application Number:
  US13/945,371
• Publication Number:
  US 20140024917A1
• Time in Patent Office: 1,160 Days
• Field of Search: 600407-480, 600/300, 600/301
• US Class Current: 1/1
• CPC Class Codes: A61B 5/0205 Simultaneously evaluating both cardiovascular conditions and different types of body conditions, e.g. heart and respiratory condition
• CPC Class Codes: A61B 5/024 Detecting, measuring or recording pulse rate or heart rate A61B5/0205, A61B5/021 take precedence
• CPC Class Codes: A61B 5/0507 using microwaves or terahertz waves
• CPC Class Codes: A61B 5/0816 Measuring devices for examining respiratory frequency measuring frequency of electric signals G01R23/00
• CPC Class Codes: A61B 5/11 Measuring movement of the entire body or parts thereof, e.g. head or hand tremor, mobility of a limb for measuring pulse A61B5/02 ;A61B5/1038 takes precedence; motion detection to correct for motion artifacts in physiological signals A61B5/721
• CPC Class Codes: A61B 5/1102 Ballistocardiography
• CPC Class Codes: A61B 5/1126 using a particular sensing technique
• CPC Class Codes: A61B 5/4809 Sleep detection, i.e. determining whether a subject is asleep or not
• CPC Class Codes: A61B 5/4836 Diagnosis combined with treatment in closed-loop systems or methods A61B5/0036 takes precedence
• CPC Class Codes: A61B 5/7225 Details of analog processing, e.g. isolation amplifier, gain or sensitivity adjustment, filtering, baseline or drift compensation A61B5/30, A61B5/316 take precedence; transformers for specific applications H01F38/00; amplifiers H03F
• CPC Class Codes: G01S 13/18 wherein range gates are used
• CPC Class Codes: G01S 13/56 for presence detection presence detection using near field arrangements G01V3/00, e.g. G01V3/08, G01V3/12; burglar, theft or intruder alarms with electrical actuation G08B13/22 - G08B13/26
• CPC Class Codes: G01S 7/282 Transmitters
• CPC Class Codes: H03B 5/187 the active element in the amplifier being a semiconductor device

Abstract

A sensor for physiology sensing may be configured to generate oscillation signals for emitting radio frequency pulses for range gated sensing. The sensor may include a radio frequency transmitter configured to emit the pulses and a receiver configured to receive reflected ones of the emitted radio frequency pulses. The received pulses may be processed to detect physiology characteristics such as motion, sleep, respiration and/or heartbeat. In some embodiments, the sensor may employ a circuit including a pulse generator configured to generate signal pulses. The circuit may also include a dielectric resonator oscillator configured to generate a radio frequency oscillating signal. A switched oscillation circuit may be coupled to the pulse generator and the dielectric resonator oscillator. The switched circuit may be configured to generate a pulsed radio frequency oscillating signal for emitting the radio frequency pulses.

Claims

1. A circuit for generating signals to produce radio frequency pulses for range gated physiology sensing, the circuit comprising:

a pulse generator configured to generate signal pulses;

a dielectric resonator oscillator configured to generate a radio frequency oscillating signal;

a switched amplifier circuit coupled to the pulse generator and the dielectric resonator oscillator, the switched amplifier circuit configured to generate a pulsed radio frequency oscillating signal in accordance with the signal pulses and radio frequency oscillating signal; and

an antenna feed coupled with an output of the switched amplifier circuit to accept the pulsed radio frequency oscillating signal and emit radio frequency pulses in accordance with the pulsed radio frequency oscillating signal via an antenna.

2. The circuit of claim 1 wherein the dielectric resonator oscillator comprises a dielectric resonator and a transistor.

3. The circuit of claim 2 wherein the transistor has a drain, a gate and a source, and wherein the dielectric resonator is coupled to the gate and to the drain of the transistor.

4. The circuit of claim 2 or 3 wherein the amplifier comprises a transistor having a drain, a gate and a source, the amplifier configured to amplify the radio frequency oscillating signal synchronously with the pulse signal to generate the pulsed radio frequency oscillating signal.

5. The circuit of claim 4 wherein the drain of the amplifier transistor is coupled to receive the signal pulses from the pulse generator.

6. The circuit of claim 4 wherein the gate of the amplifier transistor is coupled to receive the radio frequency oscillating signal from the dielectric resonator oscillator.

7. The circuit of any one of claim 2 or 3 further comprising a filter and a set of magnitude detectors coupled with the antenna feed, wherein the magnitude detectors detect signals received with the antenna feed based on signals generated from the switched amplifier circuit.

8. A circuit for generating signals to produce radio frequency pulses for range gated physiology sensing, the circuit comprising:

a pulse generator configured to generate signal pulses;

a dielectric resonator oscillator configured to generate a radio frequency oscillating signal;

a switched oscillator circuit coupled to the pulse generator and the dielectric oscillator, the switch oscillator circuit configured to generate a pulsed radio frequency oscillating signal in accordance with the signal pulses and radio frequency oscillating signal; and

an antenna feed coupled with an output of the switched oscillator circuit to accept the pulsed radio frequency oscillating signal and to emit radio frequency pulses in accordance with the pulsed radio frequency oscillating signal via an antenna.

9. The circuit of claim 8 wherein the dielectric resonator oscillator comprises a dielectric resonator and a transistor.

10. The circuit of claim 9 wherein the transistor has a drain, a gate and a source, and wherein the dielectric resonator is coupled to the gate and to the drain of the transistor.

11. The circuit of any one of claims 8 to 10 wherein the switched oscillator circuit comprises a wideband oscillator, the wideband oscillator configured to injection lock with the dielectric resonator oscillator.

12. The circuit of any one claims 8 to 10 wherein the switched oscillator circuit comprises a transistor having a drain, a gate and a source, the switched oscillator circuit including a feedback network coupled to the drain.

13. The circuit of claim 12 wherein an attenuator and matching network couples the radio frequency oscillating signal output of the dielectric resonator oscillator with the gate of the transistor of the switched oscillator circuit by a microstrip feed line coupled to the gate of the transistor of the switched oscillation circuit.

14. The circuit of claim 13 wherein the microstrip feed line is in a direct configuration.

15. The circuit of claim 13 wherein the microstrip feed line is in an indirect configuration.

16. The circuit of claim 13 wherein the pulse generator is coupled with a gate of a transistor of the switched oscillator circuit.