Fiber-optic spectrometer multi-view frequency-modulated continuous-wave lidar ranging and velocity measurement system

Abstract

The application belongs to the technical field of laser radar, and discloses a kind of ranging and velocity measurement system of frequency-modulated continuous wave laser radar based on optical fiber light splitting multi-view field, after narrow linewidth single-frequency fiber laser emits laser, into electro-optic modulator, waveform generator and microwave amplifier modulate laser carrier wave through electro-optic modulator, and modulated light is amplified by EDFA, and light splitting system is divided into N paths laser, each laser is divided into a local oscillator light and a probe light by beam splitter, probe light is emitted to object by fiber optic circulator and collimator, and the probe light emitted by target is incident to circulator, and then local oscillator light enters coupler to carry out coherent mixing, and intermediate frequency signal is obtained by balanced detector reception, after filtering and sampling, real-time N parallel fast fourier transform is carried out, and the synchronous measurement of N path distance and speed is realized using data acquisition card.The application can expand the field of view angle of laser radar and improve the angular resolution of laser radar based on multi-path distance measurement of laser radar, and overcome the problem of crosstalk.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of laser radar, and relates to a kind of ranging and velocity measurement system based on optical fiber light splitting multi-view field frequency modulation continuous wave laser radar. BACKGROUND

[0002] Laser radar is a system that actively emits laser to irradiate a target area by a transmitting system, and then detects and processes the laser echo signal reflected by the target to obtain the position, velocity and other characteristic information of the target. Since the wavelength of laser is several orders of magnitude shorter than that of microwave, it has higher angular resolution, distance resolution and velocity resolution, greater ranging distance, stronger anti-interference ability, and smaller volume and mass, and is widely used in automatic driving, weather observation, remote sensing surveying and mapping, three-dimensional imaging and industrial detection.

[0003] Traditional laser radar usually measures a unique target, cannot realize simultaneous ranging and velocity measurement, and has a measurement blind area. However, the scene of laser radar application often involves simultaneous measurement of multiple measurement targets, at which time the traditional laser radar is difficult to meet the measurement requirements.

[0004] Frequency modulation continuous wave laser radar uses a modulated signal whose frequency changes with time for detection. Compared with the traditional time-of-flight (TOF) method using pulsed laser signals, frequency modulation continuous wave does not require a high-precision timer and receiver, has no distance blind area, can provide a larger ranging range and higher resolution and sensitivity, and is theoretically not affected by ambient light and other laser emitters, has higher signal-to-noise ratio, and is safe to the human eye. SUMMARY

[0005] (I) Invention purpose

[0006] The purpose of the present application is to realize simultaneous ranging and velocity measurement of multiple targets and multiple views, and to provide a laser radar ranging and velocity measurement system and a measurement method based on the principle of optical fiber light splitting multi-view field frequency modulation continuous wave, so as to realize distance and velocity measurement of multiple targets by multiple lasers at the same time.

[0007] (II) Technical solution

[0008] In order to solve the above technical problems, the present application provides a kind of ranging and velocity measurement system based on optical fiber light splitting multi-view field frequency modulation continuous wave laser radar, it includes: narrow line width single frequency fiber laser 1, arbitrary waveform generator 2, microwave amplifier 3, electro-optic modulator 4, EDFA amplification module 5, 1×N optical fiber light splitting system 6, 1×2 optical fiber beam splitter 7-1~7-N, ring 8-1~8-N, optical fiber collimator 9-1~9-N, 2×2 optical fiber coupler 10-1~10-N, balanced detector 11-1~11-N, data acquisition module 12, target 13;

[0009] The narrow linewidth single frequency fiber laser 1 emits laser light, the output port of which is connected to the optical signal input port of the electro-optical modulator 4, the waveform output port of the arbitrary waveform generator 2 is connected to the microwave signal input port of the electro-optical modulator 4 after passing through the microwave amplifier 3, the optical signal output port of the electro-optical modulator 4 is connected to the input port of the 1×N optical fiber splitting system 6 after passing through the EDFA amplification module 5, and the N output ports of the 1×N optical fiber splitting system 6 are each independently connected to an optical processing branch, and the N optical processing branches are the same in structure and each include an optical fiber beam splitter, an optical fiber circulator, an optical fiber collimator, a 2×2 optical fiber coupler and a balanced detector connected in sequence; in one of the optical processing branches, the output port of the 1×N optical fiber splitting system 6 is connected to the input port of the 1×2 optical fiber beam splitter 7-1, and the 1×2 optical fiber beam splitter 7-1 splits the light into two beams after splitting, one of which is used as the local oscillator light and the other as the probe light, the probe light is connected to the input port 1 of the optical fiber circulator 8-1, the output port 2 of the optical fiber circulator 8-1 is connected to the port of the optical fiber collimator 9-1 and emits into the space to detect the object, the light reflected by the target object 13 is received by the optical fiber collimator 9-1, and the received optical signal is connected to the two input ports of the 2×2 optical fiber coupler 10-1 respectively with the probe light split by the output port 3 of the optical fiber circulator 8-1 and the 1×2 optical fiber beam splitter 7-1, the output port of the 2×2 optical fiber coupler 10-1 is connected to the input port of the balanced detector 11-1, and the output port of the balanced detector 11-1 is connected to the data acquisition module 12.

[0010] The narrow linewidth single frequency fiber laser 1 emits laser light, the output port of which is connected to the optical signal input port of the electro-optical modulator 4, the waveform output port of the arbitrary waveform generator 2 is connected to the microwave signal input port of the electro-optical modulator 4 after passing through the microwave amplifier 3, the optical signal output port of the electro-optical modulator 4 is connected to the input port of the 1×N optical fiber splitting system 6 after passing through the EDFA amplification module 5, and the N output ports of the 1×N optical fiber splitting system 6 are each independently connected to an optical processing branch, and the N optical processing branches are the same in structure and each include an optical fiber beam splitter, an optical fiber circulator, an optical fiber collimator, a 2×2 optical fiber coupler and a balanced detector connected in sequence; in one of the optical processing branches, the output port of the 1×N optical fiber splitting system 6 is connected to the input port of the 1×2 optical fiber beam splitter 7-1, and the 1×2 optical fiber beam splitter 7-1 splits the light into two beams after splitting, one of which is used as the local oscillator light and the other as the probe light, the probe light is connected to the input port 1 of the optical fiber circulator 8-1, the output port 2 of the optical fiber circulator 8-1 is connected to the port of the optical fiber collimator 9-1 and emits into the space to detect the object, the light reflected by the target object 13 is received by the optical fiber collimator 9-1, and the received optical signal is connected to the two input ports of the 2×2 optical fiber coupler 10-1 respectively with the probe light split by the output port 3 of the optical fiber circulator 8-1 and the 1×2 optical fiber beam splitter 7-1, the output port of the 2×2 optical fiber coupler 10-1 is connected to the input port of the balanced detector 11-1, and the output port of the balanced detector 11-1 is connected to the data acquisition module 12.

[0011] The laser emitted by the narrow line width single frequency fiber laser 1 is continuous light, the wavelength center is at 1550 nm, and the line width is less than 10 kHz.

[0012] The arbitrary waveform generator 2, the microwave amplifier 3, and the electro-optical modulator 4 constitute a linear frequency modulation signal generation module; the electro-optical modulator 4 is an IQ modulator, which is used for linear frequency modulation of the narrow line width single frequency fiber laser 1 to realize single sideband modulation under carrier suppression; the arbitrary waveform generator 2 and the microwave amplifier 3 are used to generate two orthogonal radio frequency signals as the driving signals of the electro-optical modulator 4; the waveform generated by the arbitrary waveform generator 2 is two orthogonal linear frequency modulation signals of sawtooth wave or triangular wave, and the modulated laser is single sideband modulated laser composed of positive first-order sideband or negative first-order sideband.

[0013] The devices used by the laser radar ranging and speed measuring system are all fiber devices, and the devices are connected by optical fibers.

[0014] The 1xN optical fiber splitting system 6 is used to divide the linear frequency modulation light amplified by the EDFA amplification module 5 into N equal parts as the seed light source of N channels, and the power of each modulated laser after division is greater than 40 mW.

[0015] The power splitting ratio of the N 1x2 optical fiber splitters 7-1 to 7-N is 90:10, wherein the 90% part is used as probe light, and the 10% part is used as local oscillator light.

[0016] The bandwidths of the electro-optical modulator 4, the arbitrary waveform generator 2, and the microwave amplifier 3 are all greater than 15 GHz, and the bandwidth of the balanced detector is greater than 1 GHz.

[0017] The N optical fiber collimators are arranged in the form of a curved surface.

[0018] The single sideband modulated light output after the IQ electro-optical modulator 4 has positive first-order sideband light intensity and negative first-order sideband light intensity as follows:

[0019]

[0020]

[0021] In the formula, is the input light intensity of the narrow line width single frequency laser, is the carrier frequency of the laser, is the first Bessel function, is the modulation depth, which is related to the bias voltage of the electro-optical modulator and the ratio of the half-wave voltage, is the triangular wave or sawtooth wave linear frequency modulation signal emitted by the arbitrary waveform generator;

[0022] The received signal is subjected to Fourier transform in the rising and falling bands of the triangular wave respectively, to obtain two beat frequencies f1 and f2, which are brought into the distance and velocity formula:

[0023]

[0024]

[0025] The above formula can realize the simultaneous distance measurement and velocity measurement of the object according to the linear frequency modulation continuous wave laser radar mode, wherein is the modulation period of the linear frequency modulation signal, is the modulation bandwidth of the linear frequency modulation signal, is the central wavelength of the laser.

[0026] (Three) beneficial effects

[0027] The distance and velocity measurement system based on the fiber splitting multi-view frequency modulation continuous wave laser radar provided by the above technical scheme can realize multi-view fusion detection at different distances, can simultaneously expand the field of view and provide angular resolution in a non-scanning mode, avoids the problem that the traditional laser radar large field of view detection needs to scan the galvanometer and has a higher requirement for the mechanical structure, and improves the stability of the overall system. BRIEF DESCRIPTION OF DRAWINGS

[0028] Figure 1 is a system layout schematic diagram of the embodiment of the present application.

[0029] In the figure: (1) narrow linewidth single frequency fiber laser; (2) arbitrary waveform generator; (3) microwave amplifier; (4) electro-optical modulator; (5) EDFA amplification module; (6) 1xN fiber splitting system; (7-1~7-N) 1x2 fiber beam splitter; (8-1~8-N) circulator; (9-1~9-N) fiber collimator; (10-1~10-N) 2x2 fiber coupler; (11-1~11-N) balanced detector; (12) data acquisition module; (13) target object. DETAILED DESCRIPTION

[0030] In order to make the purpose, content and advantages of the present application clearer, the specific embodiments of the present application are further described in detail below in combination with the drawings and examples.

[0031] As Figure 1As shown, the embodiment based on fiber-optic split multi-view frequency-modulated continuous wave laser ranging and velocity measurement system includes: a narrow linewidth single-frequency fiber laser 1, an arbitrary waveform generator 2, a microwave amplifier 3, an electro-optical modulator 4, an EDFA amplification module 5, a 1×N fiber-optic splitting system 6, 1×2 fiber-optic beam splitters 7-1~7-N, circulators 8-1~8-N, fiber-optic collimators 9-1~9-N, 2×2 fiber-optic couplers 10-1~10-N, balanced detectors 11-1~11-N, a data acquisition module 12, and a target object 13.

[0032] The narrow linewidth single-frequency fiber laser 1 emits laser light, the output port of which is connected to the optical signal input port of the electro-optical modulator 4. The waveform output port of the arbitrary waveform generator 2 is connected to the microwave signal input port of the electro-optical modulator 4 after passing through the microwave amplifier 3. The optical signal output port of the electro-optical modulator 4 is connected to the input port of the 1×N fiber-optic splitting system 6 after passing through the EDFA amplification module 5. The N output ports of the 1×N fiber-optic splitting system 6 are each independently connected to the input port of the 1×2 fiber-optic beam splitter 7-1~7-N. Here, the first channel is taken as an example. The 1×2 fiber-optic beam splitter 7-1 splits the output light into two paths. One path is used as the local oscillator light, and the other path is used as the probe light. The probe light is connected to the input port 1 of the circulator 8-1. The output port 2 of the circulator 8-1 is connected to the port of the fiber-optic collimator 9-1, which emits light into space to probe the target object 13. The light reflected by the target object 13 is received by the fiber-optic collimator 9-1. The received light signal is connected to the two input ports of the 2×2 fiber-optic coupler 10-1, respectively, after passing through the output port 3 of the circulator 8-1. The output port of the 2×2 fiber-optic coupler 10-1 is connected to the input port of the balanced detector 11-1. The output port of the balanced detector 11-1 is connected to the data acquisition module 12. The remaining 2~N output ports of the 1×N fiber-optic splitting system 6 are connected in the same way as the first channel.

[0033] After the narrow linewidth single-frequency fiber laser 1 emits laser light, the arbitrary waveform generator 2 and the microwave amplifier 3 modulate the laser carrier through the electro-optical modulator 4 to achieve a linear frequency modulation signal under carrier suppression. The modulated light is divided into N paths of modulated laser light through the 1×N fiber-optic splitting system 6 after passing through the EDFA amplification module 5. The N paths of modulated laser light are each independently used as the seed light source for N laser probes. N channels are parallel transmitted / received, and each channel corresponds to a different field of view. The transmission / reception fields of view of each channel are completely matched. Here, the first channel modulated laser light is taken as an example, and the remaining 2~N channel modulated laser lights are connected in the same way. Refer to Figure 1The first modulated laser is split into two beams after passing through a 1x2 optical fiber beam splitter 7-1, one of which is a local oscillator and the other is a probe light. The probe light is emitted onto an object after passing through a fiber optic circulator 8-1 and a fiber collimator 9-1, and the probe light emitted by the target is incident on the circulator 8-1 and then enters a 2x2 optical fiber coupler 10-1 to perform coherent mixing with the local oscillator. The intermediate frequency signals obtained by the above N-channel parallel transmission / reception are filtered and sampled and then subjected to real-time N-channel parallel fast Fourier transform, and a data acquisition card is used to realize synchronous measurement of the distance and speed of the N channels. The present application can expand the field of view angle of the laser radar and improve the angular resolution of the laser radar in a non-scanning mode based on multi-channel distance measurement of the laser radar, and can overcome the crosstalk problem in the traditional multi-view detection process.

[0034] The laser emitted by the narrow linewidth single-frequency fiber laser 1 is continuous light with a wavelength near 1550 nm and a linewidth less than 10 kHz, and this wavelength band is safe for the human eye.

[0035] The arbitrary waveform generator 2, the microwave amplifier 3, and the electro-optical modulator 4 form a linear frequency modulation signal generation module. The electro-optical modulator 4 is an IQ modulator (double parallel Mach-Zehnder modulator) for linear frequency modulation of the narrow linewidth single-frequency fiber laser 1, realizing single sideband modulation under carrier suppression and improving the signal-to-noise ratio of the system. The arbitrary waveform generator 2 and the microwave amplifier 3 are used to generate two orthogonal radio frequency signals as the driving signals of the electro-optical modulator 4. The waveform generated by the arbitrary waveform generator 2 is two orthogonal linear frequency modulation signals in the form of sawtooth wave or triangular wave, and the microwave amplifier 3 amplifies the power of the two orthogonal linear frequency modulation signals emitted by the arbitrary waveform generator 2 to meet the input requirements of the microwave power of the electro-optical modulator 4. The orthogonal linear frequency modulation signals emitted by the arbitrary waveform generator 2 drive the electro-optical modulator 4 to suppress the laser carrier after passing through the microwave amplifier 3, and the modulated laser is a single sideband modulated laser composed of the positive first-order sideband or the negative first-order sideband.

[0036] All the devices used in the laser radar ranging and speed measurement system of the present embodiment are fiber devices, and the devices are connected by optical fibers.

[0037] The erbium-doped fiber amplifier (EDFA amplifier 5) is used to optically amplify the weak linear frequency modulation signal after the electro-optical modulator 4, and the power of the amplified modulated laser is greater than 2 W.

[0038] The 1xN optical splitting system 6 is used to divide the linear frequency modulation light amplified by the EDFA amplification module 5 into N equal parts as the seed light source of N channels, and the power of each modulated laser after division is greater than 40 mW. Considering the loss and extinction ratio, when N is greater than or equal to 8, the 1xN optical splitting system will use multiple splitting to reduce the influence of the extinction ratio.

[0039] The power splitting ratio of the N 1x2 optical fiber splitters 7-1~7-N is 90:10, wherein the 90% part is used as the probe light and the 10% part is used as the local light.

[0040] The bandwidths of the electro-optical modulator 4, the arbitrary waveform generator 2 and the microwave amplifier 3 are all greater than 15 GHz, and the bandwidth of the balanced detector is greater than 1 GHz. The optical fiber collimator is arranged in a cambered surface form.

[0041] The laser radar ranging and speed measuring system of the embodiment does not contain any optical isolation device, so that the system can receive the reflected light signal of the moving object after emitting laser light by using the optical fiber circulator and the optical fiber collimator, to achieve the function of simultaneous transmission and reception, and reduce the complexity of the system.

[0042] All the devices used in the laser radar ranging and speed measuring system of the embodiment are optical fiber devices, and optical fiber is used to connect between each device, so as to facilitate the transportation and miniaturization of the system device.

[0043] The narrow linewidth single frequency fiber laser 1 is used to generate a seed light source with an eye-safe wavelength of 1550 nm. The carrier suppression signal of the seed light source after being modulated by the arbitrary waveform generator 2, the microwave amplifier 3 and the electro-optical modulator 4 is a single sideband modulated laser, which is composed of a positive first-order sideband or a negative first-order sideband.

[0044] The single sideband modulated light output after the IQ electro-optical modulator 4 has a positive first-order sideband light intensity and a negative first-order sideband light intensity, respectively.

[0045]

[0046]

[0047] In the formula, I0 is the input light intensity of the narrow linewidth single frequency laser, I0 is the input light intensity of the narrow linewidth single frequency laser, f0 is the carrier frequency of the laser, J0 is the first Bessel function, D is the modulation depth, which is related to the bias voltage of the electro-optical modulator and the ratio of the half-wave voltage, is the triangular wave or sawtooth wave linear frequency modulation signal emitted by the arbitrary waveform generator.

[0048] N modulated lights are each divided into two beams, one of which is used as the probe light to detect the distance and speed of the moving object, and the other of which is used as the local light for coherent homodyne detection of the received reflected light. The distance and movement speed of the object are calculated according to the frequency difference between the probe light and the local light.

[0049] The system uses optical fiber collimators 9-1~9-N to emit probe light and receive the light signal reflected by the moving object, so as to achieve the function of simultaneous receiving and transmitting of multiple fields of view. The target object 13 is a selected moving vehicle or the like.

[0050] Each modulated laser after the 1×N fiber optical splitting system 6 is split into the local oscillator light and the probe light after the 1×2 fiber beam splitter. The probe light is emitted to the object by the optical fiber circulator and the optical fiber collimator, and the probe light emitted by the target is incident to the circulator and enters the 2×2 fiber coupler to perform coherent mixing with the local oscillator light, so that the intermediate frequency signal is received by the balanced detector.

[0051] The received signal is subjected to Fourier transform in the rising frequency band and the falling frequency band of the triangular wave respectively, so as to obtain two beat frequencies f1 and f2, which are brought into the distance and speed formula:

[0052]

[0053]

[0054] According to the above formula, the simultaneous distance measurement and speed measurement of the object can be realized by the linear frequency modulation continuous wave laser radar, wherein is the modulation period of the linear frequency modulation signal, is the modulation bandwidth of the linear frequency modulation signal, is the central wavelength of the laser.

[0055] The intermediate frequency signals obtained by the above N-channel parallel emission / reception are subjected to filtering and sampling, and then subjected to real-time N-channel parallel fast Fourier transform, so that the synchronous measurement of the distance and speed of the N-channel is realized by using the data acquisition card.

[0056] As can be seen from the above technical solution, the linear frequency modulation continuous wave laser radar can be realized by using the arbitrary waveform generator and the electro-optical modulator to modulate the laser without introducing the frequency modulation nonlinearity, and by using the fiber optical splitting system, so that the high-precision distance measurement and speed measurement of the multi-view multi-target can be realized by using only one laser, the cost is effectively controlled, the measurement system is simplified, and the stability and compactness of the system are improved. In addition, the transmission power of the linear frequency modulation continuous wave laser radar is small, the wavelength is 1550 nm, which will not cause harm to people, and the linear frequency modulation continuous wave laser radar is not sensitive to the external environment and is not easy to be disturbed by the environment.

[0057] The above is only the preferred embodiment of the present application, and it should be pointed out that, for ordinary skilled persons in the technical field, some improvements and modifications can be made without departing from the technical principles of the present application, and these improvements and modifications should also be regarded as the protection scope of the present application.

Claims

1. A fiber-optic-based light-splitting multi-view frequency-modulated continuous-wave (FMCW) lidar ranging and velocity measurement system, comprising: The application relates to a single-frequency fiber laser interferometer system. The narrow-line-width single-frequency fiber laser (1) emits laser light, the output port of the laser light is connected with an optical signal input port of an electro-optic modulator (4), a waveform output port of an arbitrary waveform generator (2) is connected with a microwave signal input port of the electro-optic modulator (4) through a microwave amplifier (3), an optical signal output port of the electro-optic modulator (4) is connected with an input port of a 1*N fiber splitter (6) through an EDFA amplification module (5), N output ports of the 1*N fiber splitter (6) are independently connected with one optical processing branch, the N optical processing branches are the same in structure and each comprises a fiber splitter, a circulator, a fiber collimator, a 2*2 fiber coupler and a balanced detector which are connected in sequence; in one of the optical processing branches, the output port of the 1*N fiber splitter (6) is connected with an input port of a 1*2 fiber splitter (7-1), the 1*2 fiber splitter (7-1) splits the light into two paths, one path is used as a local oscillator light, and the other path is used as a probe light, the probe light is connected with an input port 1 of a circulator (8-1), an output port 2 of the circulator (8-1) is connected with a port of a fiber collimator (9-1) and then emits the light into the space to detect the object, the light reflected by a target object (13) is received by the fiber collimator (9-1), the received light signal is connected with the probe light split by the 1*2 fiber splitter (7-1) through an output port 3 of the circulator (8-1) and two input ports of a 2*2 fiber coupler (10-1) respectively, an output port of the 2*2 fiber coupler (10-1) is connected with an input port of a balanced detector (11-1), and an output port of the balanced detector (11-1) is connected with a data acquisition module (12). The single sideband modulation light output after the IQ electro-optic modulator (4) has positive first-order sideband light intensity and negative first-order sideband light intensity as follows: The received signal is subjected to Fourier transform in the rising frequency range and the falling frequency range of the triangular wave respectively, two beat frequencies f1 and f2 are obtained, and the beat frequencies f1 and f2 are brought into a distance and speed formula. wherein, is the input optical intensity of the narrow-linewidth single-frequency laser, is the carrier frequency of the laser, is the first-order Bessel function, is the modulation depth related to the ratio of the bias voltage and the half-wave voltage of the electro-optic modulator, is the triangular or sawtooth linear frequency modulation signal emitted by the arbitrary waveform generator; ​ From the above equation, simultaneous ranging and velocity measurement of an object can be achieved according to the chirp continuous wave laser radar method, where is the modulation period of the chirp signal, is the modulation bandwidth of the chirp signal, is the center wavelength of the laser.

2. The fiber-optic spectrometer multi-aperture FMCW CW lidar range- velocity system of claim 1 wherein, The narrow linewidth single frequency fiber laser (1) emits laser into an electro-optic modulator (4), an arbitrary waveform generator (2) and a microwave amplifier (3) modulate the laser carrier through the electro-optic modulator (4), realize the linear frequency modulation signal under the carrier suppression, and the modulated light is amplified through an EDFA amplification module (5) and then divided into N paths of modulated laser through a 1×N optical fiber splitting system (6).

3. The fiber-optic spectrometer multi-aperture FMCW CW lidar range- velocity system of claim 2 wherein, The laser emitted by the narrow linewidth single frequency fiber laser (1) is continuous light, the wavelength center is at 1550 nm, and the linewidth is less than 10 kHz.

4. The fiber-optic spectrometer multi-aperture FMCW CW lidar range- velocity system of claim 3 wherein, The arbitrary waveform generator (2), the microwave amplifier (3) and the electro-optic modulator (4) form a linear frequency modulation signal generation module; the electro-optic modulator (4) is an IQ modulator, which is used for linear frequency modulation of the narrow linewidth single frequency fiber laser (1) to realize single sideband modulation under carrier suppression; the arbitrary waveform generator (2) and the microwave amplifier (3) are used for generating two orthogonal radio frequency signals as the driving signals of the electro-optic modulator (4); the waveform generated by the arbitrary waveform generator (2) is two orthogonal linear frequency modulation signals of sawtooth wave or triangular wave, and the modulated laser is single sideband modulated laser composed of positive first-order sideband or negative first-order sideband.

5. The fiber-optic spectrometer multi-aperture FMCW CW lidar range- velocity system of claim 4 wherein, All the devices used in the laser radar ranging and speed measuring system are fiber devices, and the devices are connected by optical fibers.

6. The fiber-optic spectrometer multi-aperture FMCW CW lidar range- velocity system of claim 5 wherein, The 1×N optical fiber splitting system (6) is used for equally dividing the linear frequency modulation light amplified by the EDFA amplification module (5) into N parts as the seed light sources of N channels, and the power of each modulated laser after equal division is greater than 40 mW.

7. The fiber-optic spectrometer multi-aperture FMCW CW lidar range- velocity system of claim 6 wherein, The power division ratio of the N 1×2 optical fiber splitters (7-1~7-N) is 90:10, wherein the 90% part is used as the probe light, and the 10% part is used as the local oscillator light.

8. The fiber-optic spectrometer multi-aperture FMCW CW lidar range- velocity system of claim 7 wherein, The bandwidths of the electro-optic modulator (4), the arbitrary waveform generator (2) and the microwave amplifier (3) are all greater than 15 GHz, and the bandwidth of the balanced detector is greater than 1 GHz.

9. The fiber-optic spectrometer multi-aperture FMCW CW lidar range- velocity system of claim 8 wherein, The N optical fiber collimators are arranged in the form of a curved surface.

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