US 12,113,885 B2
Hardware-based time synchronization for heterogeneous sensors in autonomous vehicles
Xiaoling Han, San Diego, CA (US); Junjun Xin, Tucson, AZ (US); Lei Nie, Tucson, AZ (US); Yue Pan, Tucson, AZ (US); Yu Zhang, Beijing (CN); Jade E. Day, Tucson, AZ (US); Zehua Huang, San Diego, CA (US); Esayas Naizghi, Tucson, AZ (US); Pingyuan Ji, Beijing (CN); and Zhiqi Gong, Tucson, AZ (US)
Assigned to TUSIMPLE, INC., San Diego, CA (US); and BEIJING TUSEN ZHITU TECHNOLOGY CO., LTD., Beijing (CN)
Filed by TUSIMPLE, INC., San Diego, CA (US); and BEIJING TUSEN ZHITU TECHNOLOGY CO., LTD., Beijing (CN)
Filed on Feb. 26, 2021, as Appl. No. 17/186,476.
Claims priority of application No. 202011461771.2 (CN), filed on Dec. 8, 2020.
Prior Publication US 2022/0182213 A1, Jun. 9, 2022
Int. Cl. H04L 7/00 (2006.01); G01C 21/16 (2006.01); G01C 21/28 (2006.01); G01S 17/931 (2020.01); G01S 19/01 (2010.01); H04L 67/12 (2022.01)
CPC H04L 7/0016 (2013.01) [G01C 21/16 (2013.01); G01C 21/28 (2013.01); G01S 17/931 (2020.01); G01S 19/01 (2013.01); H04L 67/12 (2013.01)] 17 Claims
OG exemplary drawing
 
1. A method of synchronization in a vehicle, comprising:
generating, by a synchronization unit in the vehicle and based on a nominal pulse-per-second (PPS) signal, a plurality of output trigger pulses configured to synchronize operations of a plurality of sensors, each of the plurality of output trigger pulses having a frequency equal to an operating frequency of a corresponding sensor of the plurality of sensors, wherein the synchronization unit includes a synchronization module configured to adjust a phase of individual output trigger pulses of the plurality of output trigger pulses based on the nominal PPS signal;
receiving a reference timing signal different from the nominal PPS signal, wherein the plurality of output trigger pulses is further based on timing information derived from the reference timing signal;
transmitting the plurality of output trigger pulses to the plurality of sensors; and
obtaining, based on information from the synchronization unit, a triggered frequency of at least one of the plurality of sensors, wherein the triggered frequency is compared with a frequency provided by the synchronization module to detect abnormalities,
wherein, when a navigation unit in the vehicle coupled to the synchronization unit functions correctly, the nominal PPS signal is provided by the navigation unit, and
wherein, when the navigation unit does not function correctly, the nominal PPS signal is generated by a simulated clock source of the synchronization unit.