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Remote Heart Rate & Breathing Rate Detection
Using Near-field Diverse Wavelength, Ratiometric Differential Interferometry
In the form of Low-Power 10-GHz to 25-GHz Microwave "Doppler" [*] RADAR
Heart Sounds after Voltage to Frequency Conversion

 

 Hear Heart Sounds after Voltage to Frequency conversion hr.wav
Another View of Heart Sounds after Voltage to Frequency Conversion

CW "Doppler" [*] RADAR using GUNN Oscillator Varactor & Diode Detector (mixer)

 
Derived Amplitude Deltas 
(Detected Heart Beat Waveforms)
 
Standing Waves 
Amplitude deltas are derived as a function of Standing-Wave slope excursion. 

 

  New Implementation
In this environment there are two properties at play: Constructive and Destructive Interference, and the Doppler Effect. 

The first order effect is that of Interference, not Doppler.
Dual Standing Waves 
The Measurement is the Differential of the amplitude deltas of the two wavelengths, measured from standing-wave slope to standing-wave slope.

 
 
Remote Heart Rate Measurement System Block Diagram
Chirped Gunn Oscillator Detector diode/pre-amp Dual Sample & Hold 
for channel separation 		 VGAs for gain balancing, Differential Amplifier 
for common artifact rejection

 
One Embodiment, Schematic

 
Gain Tracking Fader Plot

Under Construction in Perpetuity
Copyright 1999 Web Author: Glen A. Williamson

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