US 12,265,178 B2
Lidar and anti-interference method therefor
Shaodong Yang, Shenzhen (CN)
Assigned to SUTENG INNOVATION TECHNOLOGY CO., LTD., Shenzhen (CN)
Filed by SUTENG INNOVATION TECHNOLOGY CO., LTD., Shenzhen (CN)
Filed on Nov. 13, 2020, as Appl. No. 17/098,233.
Application 17/098,233 is a continuation of application No. PCT/CN2020/089140, filed on May 8, 2020.
Claims priority of application No. 201910410468.0 (CN), filed on May 17, 2019.
Prior Publication US 2021/0063538 A1, Mar. 4, 2021
Int. Cl. G01S 7/48 (2006.01); G01S 7/484 (2006.01)
CPC G01S 7/4804 (2013.01) [G01S 7/484 (2013.01)] 20 Claims
OG exemplary drawing
 
1. An anti-interference method for a lidar, comprising:
modulating a transmitting time of the lidar by injecting random time jitter at a time interval in a sequence of the transmitting time,
wherein:
the random time jitter as injected comprises an injected time amount with respect to the transmitting time; and
the injected time amount comprises how much time the random time jitter leads or lags relative to the transmitting time, a positive injected time amount indicates that the random time jitter is delayed relative to the transmitting time and is to be injected after the transmitting time, and a negative injected time amount indicates that the random time jitter is to be injected ahead of the transmitting time;
transmitting a laser pulse by the lidar according to a modulated transmitting time, comprising transmitting the laser pulse by the lidar according to the injected time amount comprising one of the positive injected time amount or the negative injected time amount with respect to the transmitting time;
acquiring a receiving time of an echo received by the lidar, the echo comprising an expected echo and an unexpected echo of a local lidar, the unexpected echo comprising echoes of other lidars due to crosstalk therewith; and
identifying and removing interference echoes according to correlation between a transmitting time of the local lidar and a receiving time of an echo received by the local lidar, which comprises:
acquiring a sequence of time differences based on the transmitting time of the local lidar and the receiving time of the received echo, statistically analyzing the time differences to acquire a spatial correlation, and identifying an echo corresponding to an interference time difference whose spatial correlation is lower than a preset value as an interference echo; the time difference sequence comprises an inherent time difference between the transmitting time of the local lidar and the receiving time of the local lidar echo, and an interference time difference between the transmitting time of the local lidar and the receiving times of the echoes of other lidars, and further comprises an interference time difference between the transmitting time of the local lidar and a sporadic interference echo time of the local lidar.