US 11,946,996 B2
Ultra-accurate object tracking using radar in multi-object environment
Michael Kerner, Tel Mond (IL); John Zhonghua Wu, San Jose, CA (US); Michael Delishansky, Netanya (IL); Zohar Agon, Tel Aviv (IL); Shachar Shayovitz, Ness Ziona (IL); Michael Ney, Beer Sheva (IL); and Shay I. Freundlich, San Jose, CA (US)
Assigned to Apple, Inc., Cupertino, CA (US)
Filed by Apple Inc., Cupertino, CA (US)
Filed on Jun. 30, 2020, as Appl. No. 16/917,852.
Prior Publication US 2021/0405174 A1, Dec. 30, 2021
Int. Cl. G01S 13/28 (2006.01); G01S 13/46 (2006.01); G01S 13/48 (2006.01); G06F 3/0354 (2013.01)
CPC G01S 13/282 (2013.01) [G01S 13/48 (2013.01); G06F 3/03545 (2013.01); G01S 2013/468 (2013.01)] 26 Claims
OG exemplary drawing
 
1. A transponder for generating a predetermined delay of a first signal received at an object of interest in a radar-based object tracking system, the transponder comprising:
a receive antenna;
a receive amplifier configured for receiving, via the receive antenna, the first signal transmitted from a first radar;
a delay element configured for delaying the received first signal by a predetermined time delay;
a downconverter configured for mixing the received first signal with a first frequency source that operates with a frequency difference, wherein the frequency difference is a function of the predetermined time delay;
an upconverter configured for mixing the downconverted first signal with a second frequency source that operates with the frequency difference;
a transmit antenna; and
a transmit amplifier configured for transmitting, via the transmit antenna, a delayed first signal back to the first radar.