Wavelength division multiplexing lidar integration method and system

Abstract

The application discloses a kind of wave division multiplexing laser radar integration method and system;Among them, the method comprises using multi-wavelength laser output continuous multi-wavelength tuning laser;After multi-wavelength tuning laser passes through beam splitter, it is divided into local light and probe light;Probe light is emitted to space by laser emission subsystem;Space barrier meets probe light and generates echo signal;Through laser receiving subsystem, echo signal is received, and local light and echo signal are combined into interference signal;Interference signal is detected by photoelectric detector, and photoelectric signal is obtained;Photoelectric signal is analyzed by data processor, and the distance and speed corresponding to each wavelength of the detection object are obtained according to the analysis result.By this method, multi-line distance measurement can be obtained, and a solid-state scheme of laser radar is also realized, which improves the reliability and economy of laser radar and reduces the complexity of the system.

Description

TECHNICAL FIELD

[0001] The application belongs to the field of laser radar scanning, and particularly relates to a wavelength division multiplexing laser radar integration method and system. BACKGROUND

[0002] The laser radar technology has wide application value in the fields of vehicle-mounted, metrology, industrial measurement and the like. Compared with the TOF radar, the frequency-modulated continuous wave laser radar can realize smaller output power, longer distance detection, higher test precision and the like. The laser FMCW (Frequency Modulated Continuous Wave) is a frequency-modulated continuous wave. Its principle is shown in Figure 1 A tunable light source outputs a continuous frequency modulation signal. The frequency-modulated continuous wave is divided into two beams, one of which is used as a local oscillator, and the other is used as a measurement light. The measurement light is irradiated onto an object to be measured to generate a reverse echo. The echo light path and the local oscillator light pass through a coherent detection technology to obtain the echo time delay, that is, the transmission distance. Its schematic diagram is shown in Figure 2 Due to the good coherence of the frequency-modulated continuous wave, the detection signal and the local oscillator signal generate a beat frequency. The beat frequency signal passes through a power amplifier, an AD conversion module, and then is processed by a data processing module (DSP) to obtain frequency information.

[0003] The core components of the laser radar include a light source, a spatial scanning system, a detector, a signal processing unit and the like. Among them, the spatial scanning technology is one of the most core technologies of the laser radar. In order to obtain the depth information of the three-dimensional space, it is necessary to realize the two-dimensional irradiation of the laser. The existing methods are mainly divided into two categories, mechanical type and OPA. The first category includes traditional two-dimensional galvanometer, MEMS mirror and the like; the second category is divided into two cases, the first case is to realize two-dimensional scanning through phased array design; the second case is a flash mode, which uses a surface light source to irradiate and then uses a surface array to receive.

[0004] Since there is a very high requirement for reliability in the vehicle-mounted radar. The first category of the above-mentioned scheme has difficulty in reliability design due to the existence of moving parts. The first scheme in the second category is expected to realize all-solid-state scanning, but it involves a relatively complex integrated light design, the technology is not mature, and the light emitting points of the laser are arranged according to the dot matrix, which will form a certain diffraction sidelobe and will form a certain interference. The second scheme in the second category uses a surface array to emit, so that the peak power of a single light source is insufficient, which limits the longest working distance, and coherent detection is difficult.

[0005] Therefore, how to make the laser radar realize good spatial scanning, improve the reliability, economy and reduce the system complexity of the laser radar has become a key problem in the current research. SUMMARY

[0006] In view of the above problems, the present application provides a kind of WDM laser radar integration method and system, which can obtain multi-line distance measurement and realize laser radar solid-state scheme, improve the reliability and economy of laser radar, and reduce the complexity of system.

[0007] In one aspect, the present application provides a kind of WDM laser radar integration method, comprising:

[0008] S1, using a multi-wavelength laser to output continuous multi-wavelength tuning laser;

[0009] S2, after the multi-wavelength tuning laser passes through the beam splitter, it is divided into local light and probe light;

[0010] S3, the probe light is emitted to space by laser emission subsystem; the space obstacle meets the probe light and generates echo signal;

[0011] S4, the echo signal is received by laser receiving subsystem, and the local light and the echo signal are combined into interference signal;

[0012] S5, the interference signal is detected by photoelectric detector, and photoelectric signal is obtained;

[0013] S6, the photoelectric signal is analyzed by data processor, and the distance and speed corresponding to each wavelength of the detected object are obtained according to the analysis result.

[0014] Further, it also includes:

[0015] S7, the data processor corrects the beat frequency signal detected by the photoelectric detector according to the analysis result, to obtain more accurate beat frequency signal.

[0016] Further, the tuning method of the multi-wavelength laser includes internal tuning method and external tuning method;

[0017] The internal tuning method includes: using current or temperature or piezoelectric ceramic to continuously tune the light source;

[0018] The external tuning method includes: when the multi-wavelength laser emits fixed frequency laser, the fixed frequency laser is tuned by phase modulator.

[0019] Further, the S3 specifically includes:

[0020] S31, using wave divider to divide the signal of the probe light into different light paths according to wavelength;

[0021] S32, the signal of the probe light processed by S31 is output to space by laser emitter;

[0022] S33, the space obstacle generates a return signal after encountering the signal of the probe light.

[0023] Further, the S4 specifically comprises:

[0024] S41, receiving the return signal by a laser receiver;

[0025] S42, returning the return signal to a waveguide by a combiner;

[0026] S43, combining the return signal in the waveguide with the local light by a beam combiner to form an interference signal.

[0027] Further, the S5 specifically comprises:

[0028] S51, sending the interference signal to the photodetector according to wavelength by a wave divider;

[0029] S52, the photodetector detects the interference signal to obtain a plurality of photoelectric signals.

[0030] In another aspect, the embodiment of the present application also provides a wavelength division multiplexing laser radar integrated system, which applies the above method, and the system comprises a multi-wavelength laser, a beam splitter, a laser emission subsystem, a laser receiving subsystem, a beam combiner, a photodetector and a data processor.

[0031] The multi-wavelength laser is used for outputting continuous multi-wavelength tuning laser.

[0032] The beam splitter is used for dividing the multi-wavelength tuning laser into local light and probe light.

[0033] The laser emission subsystem is used for emitting the probe light to space.

[0034] The laser receiving subsystem is used for receiving the return signal generated by the space obstacle.

[0035] The beam combiner is used for combining the local light and the return signal to form an interference signal.

[0036] The photodetector is used for detecting the interference signal to obtain a photoelectric signal.

[0037] The data processor is used for analyzing the photoelectric signal, and obtaining the distance and speed of the detection object corresponding to each wavelength according to the analysis result.

[0038] Further, the data processor is also used for correcting the beat frequency signal detected by the photodetector to obtain a more accurate beat product signal.

[0039] Further, the laser emission subsystem comprises a wave divider and a laser emitter;

[0040] The wave divider is used for dividing the signal of the probe light into different light paths according to wavelengths.

[0041] The laser emitter is used for outputting the signal of the probe light to space.

[0042] Further, the laser emission subsystem comprises a wave divider and a laser emitter;

[0043] The laser emitter is used for outputting the signal of the probe light to space.

[0044] The wave divider is used for dividing the signal of the probe light into different light paths according to wavelengths.

[0045] Compared with the prior art, the wavelength division multiplexing laser radar integration method and system has the following beneficial effects:

[0046] The wavelength division multiplexing technology is adopted to realize the expansion of the light path output, and the laser of different wavelengths is emitted in space.

[0047] The wavelength division multiplexing technology can save the number of devices of the radar system and reduce the control difficulty.

[0048] Other features and advantages of the present application will be described in the following description, and some will become apparent from the description, or will be learned by practice of the present application. The purpose and other advantages of the present application can be achieved and obtained by the structure specifically pointed out in the written description, claims, and drawings.

[0049] The technical solutions of the present application will be further described in detail below with the help of the drawings and examples. DETAILED DESCRIPTION

[0050] The accompanying drawings are used to provide a further understanding of the present application, and constitute a part of the specification, and are used to explain the present application together with the embodiments of the present application, and do not constitute a limitation to the present application. In the drawings:

[0051] Figure 1 The wavelength division multiplexing laser radar integration method flow chart is provided for the embodiments of the present application.

[0052] Figure 2 The wavelength division multiplexing laser radar working mode one schematic diagram is provided for the embodiment 1 of the present application.

[0053] Figure 3 The wavelength division multiplexing laser radar working mode two schematic diagram is provided for the embodiment 1 of the present application.

[0054] Figure 4The working mode three schematic diagrams of the wavelength division multiplexing laser radar provided for the embodiment 1 of the present application.

[0055] Figure 5 The wavelength division multiplexing laser radar integration method schematic diagram provided for the embodiment 2 of the present application.

[0056] Figure 6 The wavelength division multiplexing laser radar integration method schematic diagram provided for the embodiment 3 of the present application.

[0057] Figure 7 The wavelength division multiplexing laser radar integration system schematic diagram provided for the embodiment of the present application. DETAILED DESCRIPTION

[0058] Exemplary embodiments of the present disclosure will be described below in greater detail with reference to the accompanying drawings. While exemplary embodiments of the present disclosure are shown in the drawings, it is understood that the present disclosure can be embodied in various forms and should not be limited by the embodiments set forth herein. Rather, these embodiments are provided so that the present disclosure can be more thoroughly understood, and the scope of the present disclosure can be accurately conveyed to those skilled in the art.

[0059] Referring to Figure 1 The embodiment of the present application provides a wavelength division multiplexing laser radar integration method, specifically comprising the following steps:

[0060] S1, using a multi-wavelength laser to output continuous multi-wavelength tuning laser;

[0061] S2, after the multi-wavelength tuning laser passes through a beam splitter, it is divided into local light and probe light;

[0062] S3, the probe light is emitted to the space by a laser emission subsystem; the space obstacle encounters the probe light and generates a return signal;

[0063] S4, the return signal is received by a laser receiving subsystem, and the local light and the return signal are combined into an interference signal;

[0064] S5, the interference signal is detected by a photoelectric detector to obtain a photoelectric signal;

[0065] S6, the photoelectric signal is analyzed by a data processor, and the distance and the speed corresponding to each wavelength of the detection object are obtained according to the analysis result;

[0066] S7, the data processor adjusts the beat frequency signal detected by the photoelectric detector and adjusts the driving and modulation signal of the multi-wavelength laser according to the analysis result.

[0067] The above steps will be described in detail below.

[0068] In the step S1, the multi-wavelength laser used in the embodiment of the application can use a DFB laser array with different wavelengths, can be realized by a multi-sideband generated by an EOM, or can be realized by splitting longitudinal modes of a mode-locked laser. The multi-wavelength laser used in the embodiment of the application is a narrow-linewidth laser. The narrow-linewidth laser means a laser with a single longitudinal mode output. In order to meet the requirements of long-distance detection and high detection accuracy, the narrow-linewidth laser usually has a small bandwidth and RIN noise.

[0069] The tuning method of the multi-wavelength laser includes an internal tuning method and an external tuning method. The internal tuning method can use current, temperature, piezoelectric ceramic, laser array and other technologies to continuously tune the light source. The external tuning method is to use a phase modulator such as an EOM to tune the fixed-frequency laser after the multi-wavelength laser emits the fixed-frequency laser. When the external tuning method is used, the RIN noise and linewidth characteristics of the narrow-linewidth laser can be better controlled. For the narrow-linewidth light source after beam combination, a single modulator can be used to realize synchronous modulation of multiple wavelengths, greatly reducing the number of required modulators. The multi-wavelength laser used in the external tuning method can use multiple narrow-linewidth lasers to form an array, or can use the multi-longitudinal mode characteristics of a mode-locked laser to generate multiple wavelengths at a time. The multi-wavelength laser can also use an EOM to generate a multi-sideband or a multi-sideband tuning method to realize multi-wavelength output. The narrow-linewidth laser can be a DFB, a VCSEL, a single-block non-planar ring cavity laser, or other solid, gaseous, semiconductor narrow-linewidth tunable lasers, or a MOPA structure laser, etc.

[0070] In the step S3, a waveguide is first used to divide the signal of the detection light into different light paths according to wavelengths. Then, a laser emitter is used to output the processed signal of the detection light to space, and a galvanometer or an OPA is used to realize scanning of the light. When the space obstacle encounters the signal of the detection light, a return signal is generated.

[0071] In the step S4, a laser receiver is first used to receive the return signal and couple the return signal into a light path. Then, a combiner is used to combine the return signal into a single waveguide. Finally, a beam combiner is used to combine the return signal in the single waveguide with the local oscillator light to generate an interference signal.

[0072] In the step S5, the interference signal is sent to the photo detector by the wave division filter; the photo detector detects the interference signal to obtain a plurality of photoelectric signals. The photo detector is a photoelectric detection array, and the device can be a positive-intrinsic-negative (PIN), an avalanche photon diode (APD), a balanced photon detector (PDB), a single photon avalanche diode (SPAD), etc.

[0073] In the step S7, the data processor (DSP) controls the driving module and the wavelength tuning module of the laser according to the analysis result, and the calibration and correction module is used to detect the tuning characteristics of the multi-wavelength laser to correct the influence of the nonlinearity of the tuning. The signal is fed back to the data processor (DSP) to demodulate the beat frequency signal detected by the photo detector (PD), and is used to adjust the driving and modulation signal of the laser. In the specific use process, the data processor can be a single-chip microcomputer, an FPGA or a waveform generator, etc. The photoelectric signal detected is analyzed into distance or speed information, the nonlinearity of the light source is analyzed, and the signal-to-noise ratio is analyzed.

[0074] The wavelength division multiplexing unit (WDM) in the embodiment of the application, i.e., the wave division filter or the wave combiner, adopts a TFF or an AWG or a WSS. The TFF is a thin film filter, the AWG is an arrayed waveguide grating, and the WSS is a wavelength selective switch. These devices are used to realize beam splitting and beam combining of a plurality of wavelengths.

[0075] The wavelength division multiplexing laser radar integrated system provided by the application is described in detail through three embodiments.

[0076] Embodiment 1

[0077] Next, the embodiment 1 of the application is described through three working modes.

[0078] The working mode one provided by the embodiment 1 of the application is specifically described with reference to the drawing Figure 2 The specific steps of the working mode one include:

[0079] S1, a narrow linewidth laser is used to output n (n≥1) narrow linewidth laser light sources with different center wavelengths to form a multi-wavelength light source array; each laser beam passes through a photoelectric modulator EOM1 to generate m-order modulation, thereby generating m×n wavelengths of laser; then a photoelectric modulator EOM2 is used to generate frequency tuning, thereby obtaining m×n wavelengths of tuned laser signals;

[0080] S2, the multi-wavelength tuning laser signal is divided into local light and probe light after passing through a beam splitter;

[0081] S3, the local light enters a correlation optical path as reference light, and the probe light generates n x m laser beams through a wavelength division multiplexing module in Figure 2 , is arranged into an array, and the n x m laser beams are emitted through an emission lens; a space obstacle, i.e., a target object in Figure 2 , generates a return signal after encountering the laser beams;

[0082] In this step, when n = m = 1, the beam splitter is not needed; m = 1 can be a special case without an EOM;

[0083] S4, when the laser receiver receives the return signal reflected by the space obstacle, the return signal is transmitted to the correlation optical path, and the return signal is combined with the local light into an interference signal.

[0084] S5, the interference signal is divided into different center wavelengths after passing through a beam splitter; n x m different wavelength interference lights are received by a receiver array in Figure 2 ;

[0085] S6, the n x m different wavelength interference lights are evaluated in frequency by a data processor, and n x m distances are obtained.

[0086] Embodiment 1 of the present application provides a working mode two, as shown in Figure 3 , the specific steps of the working mode two include:

[0087] S1, n (n > 1) narrow linewidth laser sources of different center wavelengths are output by a narrow linewidth laser to form a narrow linewidth laser array; the narrow linewidth laser array is combined into a beam by a combiner, and the combined laser is modulated by an electro-optical modulator EOM1 to generate m order tuning output, thereby generating n x m wavelength beams;

[0088] S2, the multi-wavelength tuning laser signal is divided into local light and probe light after passing through a beam splitter;

[0089] S3, the local light enters a correlation optical path as reference light, and the probe light generates n x m laser beams through a wavelength division multiplexing module in Figure 3 , is arranged into an array, and the n x m laser beams are emitted through an emission lens; a space obstacle, i.e., a target object in Figure 3 , generates a return signal after encountering the laser beams;

[0090] In this step, when n = m = 1, the beam splitter is not needed; m = 1 can be a special case without an EOM;

[0091] S4, the laser receiver transmits the echo signal reflected by the space obstacle to the relevant optical path, and combines the echo signal with the local light into an interference signal.

[0092] S5, the interference signal is divided into different wavelengths after passing through the wave divider; n*m interference lights of different wavelengths are received through the receiver array;

[0093] S6, frequency evaluation is performed on the n*m interference lights of different wavelengths through the data processor, and n*m distances are obtained.

[0094] The working mode three provided by the embodiment 1 of the present application is specifically described with reference to Figure 4 The specific steps of the working mode three include:

[0095] S1, a narrow linewidth laser array is adopted to output n (n> = 1) narrow linewidth laser light sources of different central wavelengths; the narrow linewidth laser array is combined into one beam through a combiner, the laser after the combination is modulated by an electro-optic modulator EOM1 to generate m-order tuning output, thereby generating n*m wavelength beams; the n*m wavelength beams obtain higher output power through a laser amplifier Amplifier; here, the amplifier can adopt an EDFA (Erbium-doped fiber amplifier), an SOA (semiconductor optical amplifier) and the like. The signal can be made consistent in output power of each wavelength through a GFF (gain flattening filter).

[0096] S2, the multi-wavelength tuning laser signal is divided into local light and probe light after passing through a beam splitter;

[0097] S3, the local light enters the relevant optical path as reference light; and the probe light generates n*m laser beams through a wave division multiplexing module in the wave divider, and is arranged into an array and emitted through an emission lens; the space obstacle (target object in Figure 4 Figure 4 The space obstacle (target object in

[0098] In this step, when n = 1, the wave divider is not needed;

[0099] S4, the laser receiver transmits the echo signal reflected by the space obstacle to the relevant optical path, and combines the echo signal with the local light into an interference signal.

[0100] S5, the interference signal is divided into different wavelengths after passing through the wave divider; n*m interference lights of different wavelengths are received through the receiver array;

[0101] ​S6, frequency evaluation of the n x m different wavelengths of interference light is performed by a data processor to obtain n x m distances.

[0102] Embodiment 1 of the present application proposes a method for realizing solid-state one-dimensional illumination by using a set of multi-wavelength tuning light sources and wavelength division multiplexing. Compared with the prior art, Embodiment 1 of the present application combines multi-wavelength light sources, EOM multi-sideband generation, and EOM tuning technology to realize multi-wavelength tuning laser beams; then uses the method of wavelength division multiplexing to multiplex coherent light paths; based on the present application, 100-line laser radar can be realized by combining 10 groups of laser light sources and EOM 10-order sidebands (assuming that the EOM sideband number is 10). In Embodiment 1 of the present application, the external tuning scheme can ensure that the laser has a relatively narrow linewidth.

[0103] Embodiment 2, refer to Figure 5

[0104] S1, narrow linewidth laser output n (n≥1) different center wavelength of narrow linewidth laser source, to form adjustable light source array; each light source is divided into m (m≥1) groups, combined through m combiner (i.e. wavelength division multiplexing module WDM) to synthesize m beams of light;

[0105] S2, multi-wavelength tuning laser signal is divided into local light and probe light after passing through the beam splitter;

[0106] S3, wherein the local light enters the correlation optical path as reference light; and the probe light passes through the wave divider (i.e. wavelength division multiplexing module in Figure 5 ), to generate n x m laser beams, arranged into an array, and emitted through a transmitting lens; the spatial obstacle (i.e. target object in Figure 5 ) will generate a return signal after encountering the laser beam;

[0107] S4, when the laser receiver receives the return signal reflected by the spatial obstacle, the return signal is transmitted to the m correlation optical paths, and the return signal is combined with the local light into an interference signal.

[0108] S5, the interference signal is divided into different wavelengths after passing through the wave divider; n x m different wavelengths of interference light are received by the receiver array;

[0109] S6, frequency evaluation of the n x m different wavelengths of interference light is performed by a data processor to obtain n x m distances.

[0110] ​Compared with the single-path ranging laser in the embodiment 1 of the present application, which needs a set of adjustable light source and coherent light path, the embodiment 2 of the present application multiplexes the laser source and the coherent light path by using the wavelength division multiplexing method, and uses a plurality of wavelength division multiplexing systems, which can expand the emission beam of the laser radar on the one hand, and can reduce the excessive insertion loss and low efficiency caused by excessive wavelength of the single wavelength division system on the other hand. The present application can reduce the number of lasers by using the beam splitter and the combiner in combination. The embodiment only needs 10 sets of laser light sources and 10 sets of light paths to realize 100-line laser radar ranging, thereby saving the cost.

[0111] Embodiment 3, with reference to Figure 6

[0112] S1, a narrow linewidth laser outputs n (n≥1) narrow linewidth laser light sources with different center wavelengths to form a tuning laser array; the tuning laser array is combined by a combiner to form a beam, and the combined laser passes through an electro-optical modulator EOM1 to generate m-order tuning output, thereby generating n×m wavelength beams;

[0113] S2, the multi-wavelength tuning laser signal is divided into local light and probe light after passing through a beam splitter;

[0114] S3, the local light as the reference light enters the correlation light path, and the probe light passes through a wave division multiplexer (i.e. the wave division multiplexing module in Figure 6 ), to generate n×m laser beams arranged in an array, which are emitted by a transmitting lens; the spatial obstacle (i.e. the target object in Figure 6 ) will generate a return signal after encountering the laser beam;

[0115] In this step, when n=m=1, the beam splitter is not needed; m=1 can be a special case without EOM;

[0116] S4, when the laser receiver receives the return signal reflected by the spatial obstacle, the return signal is transmitted to the m sets of correlation light paths, and the return signal is combined with the local light to form an interference signal.

[0117] S5, the interference signal is divided into different wavelengths after passing through the beam splitter; the receiver array receives n×m interference lights with different wavelengths;

[0118] S6, the data processor evaluates the frequency of the n×m interference lights with different wavelengths to obtain n×m distances.

[0119] ​Compared to the aforementioned embodiments 1 and 2, embodiment 3 utilizes an internally modulated laser array based on a wavelength division multiplexing radar. This approach reduces the number of system components, making the system more compact. Furthermore, utilizing EOM external modulation technology, the number of wavelengths can be expanded. While the previous method required 100 sets of lasers and coherent optical paths for a 100-line lidar, this embodiment achieves 100-line lidar ranging with only 10 sets of laser light sources and optical paths, saving costs.

[0120] In the attached figure Figures 2 to 6 In, E TX Represents the emission electric field strength; E RX Represents the received electric field strength; E LO Represents the local oscillator electric field strength.

[0121] The embodiment of the present invention also provides a wavelength division multiplexing laser radar integrated system, referring to Figure 7 As shown, the system includes a multi-wavelength laser, a beam splitter, a laser emission subsystem, a laser receiving subsystem, a beam combiner, a photoelectric detector and a data processor; wherein the multi-wavelength laser is used to output continuous multi-wavelength tunable laser; the beam splitter is used to separate the multi-wavelength tunable laser into local oscillator light and detection light; the laser emission subsystem is used to emit the detection light into space; the laser receiving subsystem is used to receive the echo signal generated by the space obstacle; the beam combiner is used to combine the local oscillator light and the echo signal into an interference signal; the photoelectric detector is used to detect the interference signal and obtain the photoelectric signal; the data processor is used to analyze the photoelectric signal and obtain the distance and speed corresponding to the detection object of each wavelength according to the analysis results.

[0122] The multi-wavelength laser comprises a driving module and a wavelength tuning module; the data processor is used to adjust the driving and modulation signals of the multi-wavelength laser by controlling the driving module and the wavelength tuning module.

[0123] The above-mentioned laser emission subsystem includes a wave splitter and a laser emitter; wherein the wave splitter is used to split the signal of the detection light into different optical paths according to the wavelength; the laser emitter is used to output the signal of the detection light into space.

[0124] The laser receiving subsystem includes a laser receiver and a combiner; wherein the laser receiver is used to receive the echo signal; and the combiner is used to combine the echo signal into a single waveguide.

[0125] Obviously, those skilled in the art may make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if such changes and modifications fall within the scope of the claims and their equivalents, the present invention is intended to include such changes and modifications.

Claims

1. A wavelength division multiplexing laser radar integration method, characterized in that: include: S1, using a multi-wavelength laser to output continuous multi-wavelength tunable laser; S2, passing the multi-wavelength tunable laser through a beam splitter to separate the laser into local oscillator light and probe light; S3, the detection light is emitted into space by the laser emission subsystem; when a spatial obstacle encounters the detection light, an echo signal is generated; S4. Receive the echo signal through a laser receiving subsystem, and combine the local oscillator light and the echo signal into an interference signal; S5. Detecting the interference signal with a photoelectric detector to obtain a photoelectric signal; S6. Analyzing the photoelectric signal through a data processor, and obtaining the distance and speed corresponding to the detection object at each wavelength according to the analysis results; S7, the data processor corrects the beat frequency signal detected by the photodetector according to the analysis result to obtain a more accurate beat frequency signal; The multi-wavelength laser is a narrow-linewidth laser, and the tuning method of the narrow-linewidth laser adopts an external tuning method.

2. A wavelength division multiplexing laser radar integration method according to claim 1, characterized in that: The tuning method of the multi-wavelength laser includes an internal tuning method and an external tuning method; The internal tuning method includes: using current or temperature or piezoelectric ceramics to continuously tune the light source; The external modulation method includes: after the multi-wavelength laser emits a fixed-frequency laser, a phase modulator is used to tune the fixed-frequency laser.

3. The wavelength division multiplexing laser radar integration method according to claim 1, characterized in that: The S3 specifically includes: S31, using a wavelength splitter to split the detection light signal into different optical paths according to wavelength; S32, outputting the signal of the detection light processed by S31 into space through a laser transmitter; S33. After encountering the detection light signal, the spatial obstacle generates an echo signal.

4. The wavelength division multiplexing laser radar integration method according to claim 1, wherein: The S4 specifically includes: S41, receiving the echo signal through a laser receiver; S42, returning the echo signal to the waveguide through a combiner; S43. Combine the echo signal in the waveguide and the local oscillator light into an interference signal through a beam combiner.

5. The wavelength division multiplexing laser radar integration method according to claim 1, wherein: The S5 specifically includes: S51, sending the interference signal to the photodetector according to the wavelength through a wave splitter; S52: The photoelectric detector detects the interference signal to obtain multiple photoelectric signals.

6. A wavelength division multiplexing laser radar integrated system, characterized in that: Applying the method described in any one of claims 1 to 5, the system comprises: a multi-wavelength laser, a beam splitter, a laser emission subsystem, a laser receiving subsystem, a beam combiner, a photodetector, and a data processor; The multi-wavelength laser is used to output continuous multi-wavelength tunable laser light; The beam splitter is used to split the multi-wavelength tunable laser into local oscillator light and probe light; The laser emission subsystem is used to emit detection light into space; The laser receiving subsystem is used to receive echo signals generated by space obstacles; The beam combiner is used to combine the local oscillator light and the echo signal into an interference signal; The photoelectric detector is used to detect the interference signal to obtain a photoelectric signal; The data processor is used to analyze the photoelectric signal and obtain the distance and speed corresponding to the detection object of each wavelength according to the analysis result; The data processor is further configured to correct the beat frequency signal detected by the photodetector to obtain a more accurate beat frequency signal; The multi-wavelength laser is a narrow-linewidth laser, and the tuning method of the narrow-linewidth laser adopts an external tuning method.

7. The wavelength division multiplexing laser radar integrated system according to claim 6, characterized in that: The laser emission subsystem includes a wave splitter and a laser emitter; The wavelength splitter is used to split the detection light signal into different optical paths according to wavelength; The laser transmitter is used to output the detection light signal into space.

8. The wavelength division multiplexing laser radar integrated system according to claim 6, characterized in that: The laser receiving subsystem includes a laser receiver and a combiner; The laser receiver is used to receive the echo signal; The combiner is used to combine the echo signal into the waveguide.

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