# US 2021/0333360 A1 · Anti-interference processing method and apparatus for multi-pulse laser radar system > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2021/0333360 A1 - Document ID: US20210333360A1 - Status: Published application - Kind: A1 - Application number: 17/356,443 - Filed: 2021-06-23 - Published: 2021-10-28 - Earliest claimed: 2019-05-31 - Assignees: Suteng Innovation Technology Co., Ltd. - Applicants: Suteng Innovation Technology Co., Ltd. - Inventors: Site LUO; Xia LIU; Dongshan LIU; Junpeng YANG - Web page: https://patentgrep.com/patent/US20210333360A1 ## CPC - G01S 7/4802: {using analysis of echo signal for target characterisation; Target signature; Target cross-section} - G01S 7/484: Transmitters - G01S 7/4814: {of transmitters alone} - G01S 7/487: Extracting wanted echo signals {, e.g. pulse detection} - G01S 7/4876: {by removing unwanted signals (G01S7/495 takes precedence)} - G01S 7/499: using polarisation effects - G01S 17/931: of land vehicles - G01S: RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES ## Abstract This application relates to a multi-pulse anti-interference signal processing apparatus. The multi-pulse anti-interference signal processing apparatus includes a detection pulse sending unit and a pulse receiving unit. The detection pulse sending unit is configured to emit a plurality of laser pulses to a target object based on a preset emission interval within a cycle. The pulse receiving unit is configured to receive a plurality of external signals within the cycle, obtain a reception interval between any two external signals, and determine, in the plurality of external signals based on the emission interval and the reception interval, an echo signal corresponding to the emitted laser pulses. A false echo pulse resulting from optical-to-electrical conversion and an interfering echo pulse fed back by other radar are effectively eliminated. Therefore, a signal-to-noise ratio of a target echo pulse is increased, mutual interference between a plurality of radars is effectively eliminated, and accuracy of ranging performed by a radar by using a laser pulse is improved. ## Claims ### Claim 1 A multi-pulse anti-interference signal processing method, wherein the multi-pulse anti-interference signal processing method comprises: sending a plurality of detection pulses to a detection target within a detection cycle, wherein a time interval between the plurality of detection pulses is a preset time; capturing a plurality of echo pulses generated by reflecting the plurality of detection pulses at the detection target; delaying the plurality of echo pulses by the preset time to obtain a plurality of delayed echo pulses; and obtaining a target echo pulse based on the plurality of echo pulses and the plurality of delayed echo pulses. ### Claim 2 (depends on 1) The multi-pulse anti-interference signal processing method according to claim 1, wherein after obtaining a target echo pulse based on the plurality of echo pulses and the plurality of delayed echo, the method further comprises: calculating a distance of the detection target based on a time difference between the target echo pulse and the plurality of detection pulses. ### Claim 3 (depends on 1) The multi-pulse anti-interference signal processing method according to claim 1, wherein the capturing of a plurality of echo pulses generated by reflecting the plurality of detection pulses at the detection target is specifically: capturing and performing analog-to-digital conversion on the plurality of echo pulses generated by reflecting the plurality of detection pulses at the detection target. ### Claim 4 (depends on 1) The multi-pulse anti-interference signal processing method according to claim 1, wherein the plurality of detection pulses are two detection pulses, the plurality of echo pulses are two echo pulses, and the delaying the plurality of echo pulses by the preset time to obtain a plurality of delayed echo pulses is specifically: delaying the two echo pulses based on the preset time to obtain two delayed echo pulses. ### Claim 5 (depends on 4) The multi-pulse anti-interference signal processing method according to claim 4, wherein the obtaining of a target echo pulse based on the plurality of echo pulses and the plurality of delayed echo comprises: adding up the two echo pulses and the two delayed echo pulses to generate a superposed pulse; using an absolute value of a difference between the two echo pulses and the two delayed echo pulses as a reference pulse; and using a difference obtained by subtracting the reference pulse from the superposed pulse as the target echo pulse. ### Claim 6 (depends on 1) The multi-pulse anti-interference signal processing method according to claim 1, wherein the plurality of detection pulses are three detection pulses, the plurality of echo pulses are three echo pulses, and the delaying the plurality of echo pulses by the preset time to obtain a plurality of delayed echo pulses is specifically: delaying the three echo pulses based on a first preset time to obtain first three delayed echo pulses, and delaying the three echo pulses based on a second preset time to obtain second three delayed echo pulses. ### Claim 7 (depends on 6) The multi-pulse anti-interference signal processing method according to claim 6, wherein the obtaining a target echo pulse based on the plurality of echo pulses and the plurality of delayed echo comprises: adding up the three echo pulses, the first three delayed echo pulses, and the second three delayed echo pulses to generate a triple-superposed pulse; using an absolute value of a difference between the three echo pulses and the first three delayed echo pulses as a first reference pulse; using an absolute value of a difference between the three echo pulses and the second three delayed echo pulses as a second reference pulse; using an absolute value of a difference between the first three delayed echo pulses and the second three delayed echo pulses as a third reference pulse; using an average value of a sum of the first reference pulse, the second reference pulse, and the third reference pulse as an average reference pulse; and using a difference obtained by subtracting the average reference pulse from the triple-superposed pulse as the target echo pulse. ### Claim 8 (depends on 1) The multi-pulse anti-interference signal processing method according to claim 1, wherein before the sending a plurality of detection pulses to a detection target within a detection cycle, wherein a time interval between the plurality of detection pulses is a preset time, the method further comprises: generating a plurality of detection pulses within a detection cycle; and the generating a plurality of detection pulses within a detection cycle comprises: performing collimation and polarized splitting processing on a laser pulse emitted by a laser source to obtain a pulse split bream; and performing beam combination after the pulse split bream goes through different optical paths to obtain a first group of a plurality of detection pulses; or performing beam combination after laser pulses emitted by two laser sources go through different optical paths to obtain a second group of a plurality of detection pulses. ### Claim 9 (depends on 8) The multi-pulse anti-interference signal processing method according to claim 8, wherein the performing collimation and polarized splitting processing on a laser pulse emitted by a laser source to obtain a pulse split bream, and performing beam combination after the pulse split bream goes through different optical paths to obtain a first group of a plurality of detection pulses comprises: emitting, by the laser source, a first original laser pulse, and performing collimation processing on the first original laser pulse to obtain a collimated laser pulse; performing first polarized splitting processing on the collimated laser pulse to obtain a first transmitted polarized laser pulse and a first reflected polarized laser pulse; performing second polarized splitting processing on the first transmitted polarized laser pulse to obtain a first detection pulse; performing first total reflection processing on the first reflected polarized laser pulse to obtain a first total reflected laser pulse; performing second total reflection processing on the first total reflected laser pulse to obtain a second total reflected laser pulse; performing second polarized splitting processing on the second total reflected laser pulse to obtain a second detection pulse; and combining the first detection pulse and the second detection pulse for uniform output. ### Claim 10 (depends on 8) The multi-pulse anti-interference signal processing method according to claim 8, wherein the performing beam combination after laser pulses emitted by two laser sources go through different optical paths to obtain a second group of a plurality of detection pulses comprises: emitting, by a first laser source, a second original laser pulse, and performing first collimation processing on the second original laser pulse to obtain a first collimated laser pulse; performing first total reflection processing on the first collimated laser pulse to obtain a first total reflected laser pulse; performing first polarized splitting processing on the first total reflected laser pulse to obtain a third detection pulse; emitting, by a second laser source, a third original laser pulse, and performing first polarized splitting processing on the third original laser pulse to obtain a fourth detection pulse; and combining the third detection pulse and the fourth detection pulse for uniform output. ### Claim 11 A multi-pulse anti-interference signal processing apparatus, comprising: a memory, a processor, and a computer program that is stored in the memory and capable of running on the processor, wherein when executing the computer program, the processor implements a method, the method comprising: sending a plurality of detection pulses to a detection target within a detection cycle, wherein a time interval between the plurality of detection pulses is a preset time; capturing a plurality of echo pulses generated by reflecting the plurality of detection pulses at the detection target; delaying the plurality of echo pulses by the preset time to obtain a plurality of delayed echo pulses; and obtaining a target echo pulse based on the plurality of echo pulses and the plurality of delayed echo pulses. ### Claim 12 A laser radar system, comprising: a laser emission unit; and a laser receiving unit, wherein the laser emission unit is configured to emit at least two laser pulses to a target object based on a preset emission interval within a cycle; and the laser receiving unit is configured to receive a plurality of external signals within the cycle, obtain a reception interval between any two external signals, and determine, in the plurality of external signals based on the emission interval and the reception interval, an echo signal corresponding to the emitted laser pulses. ### Claim 13 (depends on 12) The system according to claim 12, wherein the laser emission unit comprises a first laser emitter and a laser delaying optical path; the first laser emitter is configured to emit a first emitting laser pulse; and the laser delaying optical path is configured to receive the first emitting laser pulse, delay some lasers in the first emitting laser pulse, and output at least two laser pulses with an emission interval. ### Claim 14 (depends on 13) The system according to claim 13, wherein the laser delaying optical path comprises a laser splitting unit, a laser delaying unit, and a laser combination unit; the laser splitting unit is configured to split the first emitting laser pulse into a first laser pulse and a second laser pulse, send the first laser pulse to the laser delaying unit, and send the second laser pulse to the laser combination unit; the laser delaying unit is configured to delay the received first laser pulse to obtain a third laser pulse, wherein there is an emission interval between the third laser pulse and the second laser pulse; and the laser combination unit is configured to emit the received second laser pulse and third laser pulse to the target object. ### Claim 15 (depends on 13) The system according to claim 13, wherein the laser splitting unit is a first polarizing splitter, and the laser combination unit is a second polarizing splitter; the first polarizing splitter is configured to split the first emitting laser pulse into an S-polarization first laser pulse and a P-polarization second laser pulse, send the S-polarization first laser pulse to the laser delaying unit, and transmit the P-polarization second laser pulse to the second polarizing splitter; and the second polarizing splitter is configured to receive the P-polarization second laser pulse and output the P-polarization second laser pulse through transmission, and receive an S-polarization third laser pulse and output the third laser pulse through reflection. ### Claim 16 (depends on 15) The system according to claim 15, wherein the laser delaying unit comprises a first total reflection prism and a second total reflection prism; the first total reflection prism is configured to reflect the first laser pulse to the second total reflection prism; and the second total reflection prism is configured to reflect the received laser pulse to the second polarizing splitter. ### Claim 17 (depends on 16) The system according to claim 16, wherein a distance of an optical path formed by an element in the laser delaying unit and an element in the laser splitting unit is adjustable, and a length of the distance is related to duration of the emission interval. ### Claim 18 (depends on 12) The system according to claim 12, wherein the laser emission unit comprises a second laser emitter, a third laser emitter, and a laser combination optical path; the second laser emitter and the third laser emitter emit a second emitting laser pulse and a third emitting laser pulse within the cycle; and the laser combination optical path is configured to combine the second emitting laser pulse and the third emitting laser pulse, and emit a combined laser pulse to the target object. ### Claim 19 (depends on 18) The system according to claim 18, wherein an emission interval for emitting a laser pulse by the second laser emitter and the third laser emitter is adjustable. ### Claim 20 (depends on 19) The system according to claim 19, wherein the second emitting laser pulse is of S polarization, the third emitting laser pulse is of P polarization, and the laser combination optical path comprises a third polarized splitter and a third total reflection prism; the third total reflection prism is configured to reflect the second emitting laser pulse to the third polarizing splitter; and the third polarizing splitter is configured to output, through reflection, the laser pulse sent by the third total reflection prism, and output the third emitting laser pulse through transmission.