US 11,874,362 B2
Integrated two-dimensional multi-beam lidar transmitter based on butler matrix
Liangjun Lu, Shanghai (CN); Chen Zhu, Shanghai (CN); Linjie Zhou, Shanghai (CN); Jiao Liu, Shanghai (CN); and Jianping Chen, Shanghai (CN)
Assigned to Shanghai Jiao Tong University, Shanghai (CN)
Filed by Shanghai Jiao Tong University, Shanghai (CN)
Filed on Oct. 1, 2020, as Appl. No. 17/061,126.
Application 17/061,126 is a continuation of application No. PCT/CN2019/084897, filed on Apr. 29, 2019.
Claims priority of application No. 201811484764.7 (CN), filed on Dec. 6, 2018.
Prior Publication US 2021/0018603 A1, Jan. 21, 2021
Int. Cl. G01S 7/4911 (2020.01); G01S 7/481 (2006.01); G02B 6/12 (2006.01); G02B 6/293 (2006.01)
CPC G01S 7/4911 (2013.01) [G01S 7/4815 (2013.01); G02B 6/12007 (2013.01); G02B 6/29395 (2013.01)] 10 Claims
OG exemplary drawing
 
1. An integrated two-dimensional multi-beam LiDAR transmitter based on a Butler matrix, comprising
a tunable laser array,
a frequency modulated continuous wave modulator array,
an N×N Butler optical matrix network,
an N×M optical beam expanding network,
an M-path phase shifter array, and
an M-path two-dimensional LiDAR emitters,
wherein the tunable laser array is a narrow linewidth laser array, and N-path narrow linewidth continuous light output by the tunable laser array passes through the frequency modulated continuous wave modulator array to generate N-path frequency modulated continuous wave signals;
after being processed by the N×N Butler matrix network and the N×M optical beam expanding network, the energy of each path of the frequency modulated continuous optical signal is evenly distributed to M-path output ports, and output signals of adjacent output ports have equal phase differences;
the M-path phase shifter array generates equal-difference phases with continuously tunable phase differences for the M-path optical signals output by the M-path output ports;
the M-path optical signals with continuously adjustable phase differences are transmitted by the M-path two-dimensional LiDAR emitters so that no more than N different two-dimensional steerable optical beams are realized, wherein N=2n (n=1, 2, . . . ), M=2K×N (K=1, 2, . . . ).