US 11,754,711 B2
Frequency chirp for lidar for high-velocity targets
Daniel J. Klemme, Shakopee, MN (US); Pierre Asselin, Richfield, MN (US); and Zoran Jandric, St. Louis Park, MN (US)
Assigned to LUMINAR TECHNOLOGIES, INC., Orlando, FL (US)
Filed by Seagate Technology LLC, Cupertino, CA (US)
Filed on Mar. 5, 2020, as Appl. No. 16/810,736.
Claims priority of provisional application 62/955,598, filed on Dec. 31, 2019.
Prior Publication US 2021/0199803 A1, Jul. 1, 2021
Int. Cl. G01S 17/34 (2020.01); G01S 7/48 (2006.01); G01S 17/89 (2020.01)
CPC G01S 17/34 (2020.01) [G01S 7/4808 (2013.01); G01S 17/89 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A method comprising:
emitting a frequency-modulated continuous light beam that, over time, includes an up region, a down region, and a flat region, wherein the up region includes increasing a frequency of the continuous light beam, the down region includes decreasing the frequency of the continuous light beam, and the flat region includes maintaining the frequency of the continuous light beam at a constant frequency;
detecting backscattered light;
determining a magnitude of a Doppler frequency shift based only on the detected backscattered light responsive to the flat region and not based on the detected backscattered light responsive to the up region and the down region; and
determining, based at least in part on the determined magnitude of the Doppler frequency shift, a velocity of a target.