US 12,092,758 B2
Method and apparatus for doppler radar signal recovery of target displacement
Jenshan Lin, Gainesville, FL (US); and Te-Yu Kao, Gainesville, FL (US)
Assigned to UNIVERSITY OF FLORIDA RESEARCH FOUNDATION, INC., Gainesville, FL (US)
Filed by University of Florida Research Foundation, Inc., Gainesville, FL (US)
Filed on Aug. 5, 2019, as Appl. No. 16/531,902.
Application 16/531,902 is a continuation of application No. 14/631,532, filed on Feb. 25, 2015, granted, now 10,401,477.
Claims priority of provisional application 61/949,136, filed on Mar. 6, 2014.
Claims priority of provisional application 61/944,428, filed on Feb. 25, 2014.
Prior Publication US 2019/0353752 A1, Nov. 21, 2019
Int. Cl. G01S 7/41 (2006.01); A61B 5/00 (2006.01); A61B 5/0205 (2006.01); A61B 5/024 (2006.01); A61B 5/05 (2021.01); A61B 5/08 (2006.01); G01S 13/50 (2006.01)
CPC G01S 7/41 (2013.01) [A61B 5/0205 (2013.01); A61B 5/024 (2013.01); A61B 5/05 (2013.01); A61B 5/0816 (2013.01); A61B 5/7257 (2013.01); G01S 13/50 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A radar system, comprising:
a transmit (TX) antenna and a receive (RX) antenna on a substrate;
a radio frequency (RF) front end on the substrate, the RF front end comprising transmit circuitry coupled to the TX antenna and receive circuitry coupled to the RX antenna, where the transmit circuitry is configured to generate a transmit signal having a wavelength, λ, directed at a side of a target via the TX antenna, and the receive circuitry is configured to process a reflected signal received via the RX antenna to create a receive signal, the reflected signal having the wavelength, λ, and produced by reflection of the transmit signal from the side of the target, where the reflected signal is based, at least in part, on a first vibration and a second vibration of the target;
intermediate frequency (IF) circuitry on the substrate, the IF circuitry configured to demodulate the receive signal to produce a baseband output B(t), where

OG Complex Work Unit Math
 where ϕt is a total accumulated residual phase, and x(t)=mr sin(2πfrt)+mh sin(2πfht), and S(t)=BI(t)+jBQ(t), where

OG Complex Work Unit Math
with fr and mr being a frequency and an amplitude of the first vibration of the target, and fh and mh being a frequency and an amplitude of the second vibration of the target; and
baseband processing circuitry configured to determine the frequency fh of the second vibration from a frequency spectrum of S(t) comprising recovered portions of BI(t) or recovered portions of BQ(t) that replaced corresponding distorted portions of BI(t) or corresponding distorted portions of BQ(t) identified by the baseband processing circuitry, wherein the baseband processing circuitry identifies the corresponding distorted portions of BI(t) or the corresponding distorted portions of BQ(t) produced by system nonlinearity, and replaces the corresponding distorted portions of BI(t) or the corresponding distorted portions of BQ(t) with the recovered portions of BI(t) or the recovered portions of BQ(t).