US 12,406,507 B2
Time-division multiple access scanning for crosstalk mitigation in light detection and ranging (lidar) devices
Georges Goetz, Mountain View, CA (US); James Dunphy, San Jose, CA (US); Augusto Tazzoli, San Jose, CA (US); and David Schleuning, Piedmont, CA (US)
Assigned to Waymo LLC, Mountain View, CA (US)
Filed by Waymo LLC, Mountain View, CA (US)
Filed on Aug. 23, 2022, as Appl. No. 17/821,535.
Prior Publication US 2024/0071093 A1, Feb. 29, 2024
Int. Cl. G06V 20/58 (2022.01); B60W 60/00 (2020.01)
CPC G06V 20/58 (2022.01) [B60W 60/0015 (2020.02); B60W 2420/408 (2024.01); B60W 2554/4049 (2020.02)] 20 Claims
OG exemplary drawing
 
1. A method comprising:
emitting, from a first group of light emitters of a light detection and ranging (lidar) device, a first group of light signals into a surrounding environment, wherein the first group of light signals corresponds to a first angular resolution with respect to the surrounding environment;
detecting, by a first group of light detectors of the lidar device during a first listening window, a first group of reflected light signals from the surrounding environment, wherein the first group of reflected light signals corresponds to reflections of the first group of light signals from objects in the surrounding environment;
emitting, from a second group of light emitters of the lidar device, a second group of light signals into the surrounding environment, wherein the second group of light emitters of the lidar device represents a subset of the first group of light emitters of the lidar device, wherein the second group of light signals corresponds to a second angular resolution with respect to the surrounding environment, and wherein the second angular resolution is lower than the first angular resolution;
detecting, by a second group of light detectors of the lidar device during a second listening window, a second group of reflected light signals from the surrounding environment, wherein the second group of light detectors of the lidar device represents a subset of the first group of light detectors of the lidar device, wherein the second group of reflected light signals corresponds to reflections of the second group of light signals from objects in the surrounding environment, and wherein a duration of the second listening window is shorter than a duration of the first listening window; and
synthesizing, by a controller of the lidar device, a dataset usable to generate one or more point clouds, wherein the dataset is based on the detected first group of reflected light signals and the detected second group of reflected light signals, and wherein synthesizing the dataset comprises, for each of the detected reflected light signals in the second group of detected reflected light signals:
determining a second target distance based on the respective detected reflected light signal;
determining a first target distance based on a corresponding detected reflected light signal in the first group of detected reflected light signals, wherein the corresponding detected reflected light signal in the first group of detected reflected light signals was detected by the same light detector within the lidar device;
determining a difference between the second target distance and the first target distance; and
including the second target distance or the first target distance in the dataset if the difference is less than a threshold difference value.