CN115754989A - Three-dimensional solid-state laser radar chip and detection method and system thereof - Google Patents

Abstract

The invention discloses a three-dimensional solid-state laser radar chip and its detection method and system, including a laser, a first optical coupler, a first micro-ring resonator, a second micro-ring resonator, a first optical amplifier, and a second optical amplifier , second optical coupler, 90° optical mixer, first balanced detector, second balanced detector, 1×N power divider, phase shifter array, grating antenna array, and optical waveguides between photonic components Connection; the invention realizes the scanning of the light beam in one dimension through the frequency dispersion technology, the laser frequency-detection angle mapping can be realized by a single grating antenna, the scanning of the spatial beam in another dimension is realized based on the phase shifter array, and the phase shifter array is adjusted to make the phase shifter array Adjacent channel light fields have the same phase difference, realizing the mapping of adjacent channel phase difference-detection angle; two scanning methods combined with frequency modulation continuous wave radar detection technology and coherent reception can realize target distance, position and speed information acquisition.

Description

A three-dimensional solid-state laser radar chip and its detection method and system

technical field

The invention relates to the technical field of integrated photons, in particular to a three-dimensional solid-state laser radar chip and a detection method and system thereof.

Background technique

Lidar can realize high-precision three-dimensional perception and is widely used in autonomous driving, intelligent robots, remote sensing and other fields. At present, more mature lidar systems use mechanical scanning combined with pulse time arrival technology to obtain three-dimensional/two-dimensional spatial distribution information of detection targets. However, due to the complex structure of mechanical rotating parts, poor vibration resistance, and easy wear and tear, mechanical laser The life of the radar is limited, and the installation and calibration process is cumbersome and bulky, so it is limited in consumer-level application scenarios. At the same time, solid-state beam steering technologies based on mechanisms such as integrated optical phased arrays, optical crystal waveguides, and dispersive media are also developing rapidly. For example, the rapid scanning of the laser beam is realized by electronic control/thermal control, which has better stability and compact system compared with mechanical scanning, (see [S. Miller, Y. Phare, M. Shin, etc, "Large -scale optical phased array using a low-power multi-pass silicon photonic platform," Optica , vol. 7, no. 1, pp. 3-6, 2020.]). Using optical solitons to excite optical frequency combs and performing large-scale parallel coherent laser ranging based on frequency (wavelength) dispersion-direction mapping can also achieve solid-state fast scanning of laser beams in one dimension, (see [J. Riemensberger, A. Lukashchuk, M. Karpov, etc, "Massivelyparallel coherent laser ranging using a soliton microcomb," Nature , vol. 581,164-170, 2020.] ). Although the above-mentioned related technologies are still mainly in the stage of laboratory research, the solid-state beam control technology has attracted academic and industrial circles to solve its technical difficulties under new requirements due to its potential superior characteristics, and invented (see [Guo Qingshui, Yin Kun , Chai Tian, Liu Shiyuan, "A three-dimensional solid-state laser radar detection method and device based on dual optical frequency combs", CN113820688A.]) proposed a solution, a three-dimensional solid-state laser radar detection device based on dual optical frequency combs, combined with frequency Dispersive beam scanning technology, Rotman optical lens beam direction control technology and dual optical frequency comb coherent receiving technology realize multi-channel data reception at the same time, and can realize high-precision measurement of target three-dimensional spatial distribution and velocity information without mechanical scanning. However, the solid-state lidar detection device of this solution can only scan in one dimension at the same time, and still requires large-scale discrete devices, resulting in a large system device and high cost.

Contents of the invention

The purpose of the present invention is to provide a three-dimensional solid-state laser radar chip and its detection method and system. Based on the optical frequency comb dispersion mechanism and phase shifter array phase control, the laser radar can simultaneously scan in two dimensions, combined with frequency modulation continuous wave radar Detection technology and coherent reception realize the acquisition of high-resolution target distance and velocity information. Based on two optical frequency comb difference frequency multiplexing and coherent detection technology, two detectors can realize simultaneous reception of all channel data. Based on III-V Family device chips and silicon photonic chips are monolithically integrated to realize LiDAR monolithic integration. The whole system is pure solid state, without mechanical scanning to control the beam direction, the system structure is simple and compact, and can be integrated.

To achieve the above object, the present invention provides the following technical solutions:

The invention discloses a three-dimensional solid-state laser radar chip, including a laser, a first optical coupler, a first microring resonant cavity, a second microring resonant cavity, a first optical amplifier, a second optical amplifier, and a second optical coupler , 90° optical mixer, first balanced detector, second balanced detector, 1×N power divider, phase shifter array, grating antenna array, each photonic component is connected by an optical waveguide;

The output end of the laser is connected to the input end of the first optical coupler, and the output end of the first optical coupler is respectively connected to the first microring resonator and the second microring resonator with different radius sizes, and the first microring resonator The output ends of the cavity and the second microring resonator are respectively connected to the input ends of the first optical amplifier and the second optical amplifier, and the output ends of the first optical amplifier and the second optical amplifier are respectively connected to one of the ports of the second optical coupler and One input end of the 90° optical mixer, the other two ports of the second optical coupler are respectively connected to the input end of the 1×N power divider and the other input end of the 90° optical mixer, the 1 The N output ends of the ×N power divider are connected to the N input ends of the phase shifter array, the N output ends of the phase shifter array are connected to the N input ends of the grating antenna array, and the four 90° optical mixers The output ends are respectively connected to the input ends of the first balanced detector and the second balanced detector.

Preferably, the laser, the first optical amplifier, and the second optical amplifier are made of materials that can be integrated with silicon optical chips, and the materials include indium phosphide, gallium arsenide, and nitrogen based on III-V process platforms. gallium chloride.

Preferably, the first microring resonator, the second microring resonator, the first optical coupler, the second optical coupler, the 90° optical mixer, the 1×N power divider, and the phase shifter array , the grating antenna array, the first balanced detector and the second balanced detector are devices prepared based on a silicon photonics process platform.

Preferably, the first microring resonator and the second microring resonator are used to excite the chirp signal output by the laser into multiple comb sidebands by generating dissipative Kerr solitons to generate linearly swept light Frequency comb signal: the radius of the microrings of the first microring resonator and the second microring resonator are different in size, corresponding to different repetition frequencies of the optical frequency comb.

Preferably, the frequency responses of the first balanced detector pair and the second balanced detector pair cover all intermediate frequency signals of the lidar.

The invention discloses a detection method based on the above-mentioned three-dimensional solid-state laser radar chip, comprising the following steps:

Step 1. The chirped optical signal generated by the laser is sent to the input end of the first optical coupler, and the first optical coupler divides the optical signal into two paths and sends them to the first microring resonator and the second microring resonator respectively Cavity;

Step 2. The chirped optical signal excites the first microring resonator to generate a linearly swept detection optical frequency comb signal, excites the second microring resonator to generate a linearly swept reference optical frequency comb signal, and The detection optical frequency comb signal and the reference optical frequency comb signal are respectively sent to the first optical amplifier and the second optical amplifier for amplification; the amplified detection optical frequency comb signal is sent to the 1×N power divider through the second optical coupler , the amplified reference optical frequency comb signal is sent to the 90° optical mixer;

Step 3. The 1×N power divider divides the amplified detection optical frequency comb signal into N paths, and sends them to N phase shifter arrays from the output terminals of the 1×N power divider, and the phase shifter array Perform phase regulation on the N-channel detection optical frequency comb signal, and the N-channel phase-regulated detection optical frequency comb signal is sent from the N output terminals of the phase shifter array to the input terminal of the grating antenna array with a number of N, and the detection optical signal passes through the grating The antenna array radiates into space;

Step 4. After the detection optical signal encounters the target, it is reflected back to the grating antenna array to obtain the received optical signal. The received optical signal is sent to the phase shifter array by the grating antenna array, and then sent to the 1×N power divider by the phase shifter array. N ports are sent to the 90° optical mixer through the second optical coupler;

Step 5. The received optical signal and the reference optical signal enter the first balanced detector and the second balanced detector to complete coherent detection to obtain a complex intermediate frequency signal carrying target information. After signal acquisition of the complex intermediate frequency signal, the target 3D is obtained based on the radar signal algorithm Spatial distribution and velocity information.

Preferably, in the step 1, the chirp method for generating the chirped optical signal by the laser includes but not limited to sawtooth chirp, triangular wave chirp, and segmental chirp.

Preferably, in step 3, a single grating antenna in the grating antenna array controls different comb-tooth sweep frequency sub-signal beams of the detection optical signal based on frequency dispersion to point to 2M+1 different directions simultaneously on the θ plane, where M is The number of single-sided optical frequency comb teeth can obtain 2M+1 detection sub-optical signals pointing in different directions to realize the scanning of the optical beam in the dimension of the θ plane, and at the same time realize the optical The scanning of the beam in another dimension perpendicular to the direction of the θ plane.

The invention also discloses a detection system based on the above-mentioned three-dimensional solid-state laser radar chip, the system includes the three-dimensional solid-state laser radar chip and a signal acquisition and processing unit, The first balanced detector in the radar chip is connected to the radio frequency output end of the second balanced detector. The three-dimensional solid-state laser radar chip is based on the optical frequency comb dispersion mechanism and the phase shifter array phase regulation, and is used to realize the laser radar in two Simultaneously scan the target; the signal acquisition and processing unit is used to collect and process the target information scanned by the three-dimensional solid-state lidar chip, and combine frequency modulation continuous wave radar detection technology and coherent reception to achieve target distance, position and speed information acquisition .

Beneficial effects of the present invention:

1) The present invention realizes one-dimensional scanning of optical beams through frequency dispersion technology, a single grating antenna can realize laser frequency-detection angle mapping, realizes scanning of another dimension of spatial beams based on a phase shifter array, and adjusts the phase shifter array to make The light fields of adjacent channels have the same phase difference, realizing the mapping of adjacent channel phase difference-detection angle; the two scanning methods combined with frequency modulation continuous wave radar detection technology and coherent reception can realize the acquisition of target distance, position and speed information. The scanning speed of the scheme is fast, the system is pure solid state, the structure is simple and no mechanical scanning is required.

2) The detection optical signal and reference optical signal of the present invention are based on the same laser chirp, drive two silicon nitride microring resonators with slightly different radii, and generate detection optical frequency comb signals and reference light through the dissipative Kerr soliton effect Frequency comb signal, based on the above-mentioned two optical frequency comb signal difference frequency multiplexing and coherent detection technology, two balanced detectors can realize simultaneous reception of all channel data.

3) The present invention is based on devices such as monolithic integrated lasers, optical amplifiers, silicon-based microring resonators, optical couplers, balanced detectors, 90° optical mixers, phase shifter arrays, and grating antenna arrays, to realize laser radar single Chip integration, compact and simple system, small size.

Description of drawings

Fig. 1 is the structural representation of three-dimensional solid-state lidar chip of the present invention;

Fig. 2 is the structural representation of a specific embodiment of the detection system based on the three-dimensional solid-state laser radar chip of the present invention;

Fig. 3 is a diagram of the mapping relationship between detection sub-optical signals, received optical signals, complex intermediate frequency electrical signals, etc. in the embodiment of the solid-state lidar detection system of the present invention.

Fig. 4 is the spatial relation of the chip surface, the θ plane, and the scanning angle ϕ _O in the direction perpendicular to the θ plane in the embodiment of the solid-state lidar detection system of the present invention.

Detailed ways

In order to make the object, technical solution and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. However, it should be understood that the specific embodiments described here are only used to explain the present invention, and are not intended to limit the scope of the present invention. Also, in the following description, descriptions of well-known structures and techniques are omitted to avoid unnecessarily obscuring the concept of the present invention.

As shown in Figure 1, an embodiment of the present invention provides a three-dimensional solid-state lidar chip, including: a laser, a first optical coupler (OC1), a first microring resonator, a second microring resonator, and a first optical amplifier , second optical amplifier, second optical coupler (OC2), 90° optical mixer, first balanced detector (BPD1), second balanced detector (BPD2), 1×N power splitter, phase shifter Arrays, grating antenna arrays, and photonic components are connected through optical waveguides.

Wherein, the output end of the laser is connected to the input end of the first optical coupler, and the output end of the first optical coupler is respectively connected to the first microring resonator and the second microring resonator of silicon nitride, and the first microring The output end of the resonant cavity is connected to the input end of the first optical amplifier, the output end of the second microring resonant cavity is connected to the input end of the second optical amplifier, and the output end of the second optical amplifier is connected to an input end of the 90° optical mixer , the output end of the first optical amplifier is connected to the port 1 of the second optical coupler, the port 2 of the second optical coupler is connected to the input end of the 1×N power divider, and the N output ends of the 1×N power divider are connected to the shifter N input terminals of the phaser array, N output terminals of the phase shifter array are connected to N input terminals of the grating antenna array, and port 3 of the second optical coupler is connected to another input terminal of the 90° optical mixer, 90 ° The four output terminals of the optical mixer are respectively connected to the input terminals of the first balanced detector and the second balanced detector.

The laser, the first optical amplifier, and the second optical amplifier are lasers and optical amplifiers that can be integrated on-chip with silicon optical chips, and their materials include but are not limited to indium phosphide, gallium arsenide, nitrogen GaN, etc. or other materials that can be integrated with silicon photonics chips.

The first microring resonator and the second microring resonator include but are not limited to silicon nitride devices prepared on a silicon photonics process platform, which are used to excite the chirp signal output by the laser by generating dissipative Kerr solitons A plurality of comb sidebands generate a linearly swept optical frequency comb signal; the microring radii R1 and R2 of the first microring resonator and the second microring resonator are different, corresponding to different repetition frequencies of the optical frequency comb.

The first optical coupler, the second optical coupler, the 90° optical mixer, the 1×N power splitter, the phase shifter array, and the grating antenna array include, but are not limited to, devices prepared based on a silicon photonics process platform.

The first balanced detector and the second balanced detector include but are not limited to devices made of materials such as germanium and silicon based on the silicon photonics process platform; the frequency response of the first balanced photodetector pair and the second balanced photodetector pair covers laser All IF signals of the radar.

As shown in Figure 2, an embodiment of a detection system based on a three-dimensional solid-state laser radar chip is as follows, the system includes the three-dimensional solid-state laser radar chip and a signal acquisition and processing unit, the signal acquisition and processing unit is connected with the first balance detector and The RF output of the second balanced detector is connected. The three-dimensional solid-state laser radar chip is based on the optical frequency comb dispersion mechanism and phase shifter array phase control, and realizes simultaneous scanning of the target by the laser radar in two dimensions; the signal acquisition and processing unit is used to collect and process the three-dimensional solid The target information scanned by the lidar chip is combined with frequency modulation continuous wave radar detection technology and coherent reception to achieve target distance, position and speed information acquisition.

For ease of understanding, the technical solution of the present invention will be described in detail below through specific embodiments of the detection method and system based on the three-dimensional solid-state laser radar chip, as follows:

The laser is used as a light source to generate a sawtooth linear frequency-modulated optical signal with a center frequency of fs and a sweep frequency of f _LFM = k t (0≤t≤T). The optical signal generated by the laser drives two silicon nitride microstructures with different radii The ring resonator produces optical frequency combs with the same center frequency and repetition frequencies f _PRF1 and f _PRF2 respectively. The repetition frequency difference between the center frequencies of the two optical frequency combs is ∆ f _PRF (assuming f _PRF1 is slightly greater than f _PRF2 ). The spectrum of the optical frequency comb signal output by the first silicon nitride microring resonator is composed of f _s + if _{PRF 1} ( i =- M ,- M +1,..., M ) components, which are input as detection optical frequency comb signal 1×N At the input end of the power divider, the second silicon nitride microring resonator output optical frequency comb signal spectrum is composed of f _s + if _{PRF 2} ( i =- M ,- M +1,…, M ) components, as the reference light The signal is input to one input end of the 90° optical mixer, where M is the number of comb teeth of the single-sided optical frequency comb, and f _s is the center frequency of the central comb teeth of the optical frequency comb. Wherein the detection optical frequency comb signal S _comb1 ( t ) can be specifically expressed as:

；

;

Among them, A _{i_1} ( i =- M ,- M +1,…, M ) is the amplitude of the different sweeping comb signals of the detection optical frequency comb signal, 0≤t ≤T is the time, k is the frequency modulation slope, and T is the cycle. Similarly, the reference optical frequency comb signal S _comb2 ( t ) can be specifically expressed as:

；

;

Among them, A _{i_2} ( i =- M ,- M +1,..., M ) is the amplitude of the different frequency-sweeping comb signals of the reference optical frequency comb signal. an input terminal of the frequency converter.

As shown in Figure 3, the detection optical frequency comb signal is sent to the input end of the second optical coupler after being amplified by the first optical amplifier, and the second optical coupler sends it to the 1×N power divider, and the 1×N power divider The output port of the device is connected to the phase shifter array containing N input ports one by one, and the 1×N power divider divides the detection optical frequency comb signal and sends it to the N input ports of the phase shifter array, and the phase shifter array Perform phase regulation on the detection optical frequency comb signal on each channel, and the detection optical frequency comb signal is sent from the N output terminals of the phase shifter array to the input terminals of N grating antenna arrays, and radiated to the space through the grating antenna array In , a single grating antenna is based on frequency dispersion control to detect different comb-tooth sweep sub-signal beams on the θ plane pointing to 2M+1 ( M is the number of single-sided optical frequency comb teeth) different directions at the same time, resulting in 2M+1 There are two detection sub-light signals pointing in different directions, the pointing angle is θ _i , i =1,2,...,2M + 1, θ _i has a mapping relationship with the optical comb signal with different center frequencies, and the light beam is realized in the θ plane. scanning in one dimension, and at the same time realize the scanning of the light beam in another dimension perpendicular to the θ plane direction by adjusting the phase of adjacent channels of the phase shifter array, the phase difference between adjacent channels is ∆ ϕ , and the grating antenna array sends N channels The frequency comb signal is scanned at a scanning angle ϕ _O in the direction perpendicular to the θ plane, ϕ _O is the angle between the beam scanned in the direction perpendicular to the θ plane and the θ plane, the angular spatial relationship is shown in Figure 4, the phase difference ∆ ϕ and the scanning angle ϕ _O has a mapping relationship, which can be specifically expressed as:

；

;

Where λ is the wavelength of the detection optical frequency comb signal, d is the distance between adjacent channels of the grating antenna array, and the scanning of the optical beam in the dimension perpendicular to the θ plane can be realized by adjusting the phase difference ∆ϕ between adjacent channels of the phase shifter array. The detection light signal in the space is reflected after encountering the target, and the target reflected signal is received by the grating antenna array at the same time, and then sent to the second optical coupler through the phase shifter array and 1×N power splitter, and then passed through the second optical coupler. The reflector sends the target reflection signal to the other input end of the 90° optical coupler to achieve coherent reception with the reference optical signal. Assuming that the detection optical signal with an angle of θ _i detects the target, the delay difference between the target reflection signal and the reference optical signal corresponding to the sub-signal is τ _i . The velocity of the corresponding target is v _i , and the Doppler frequency shift introduced by the target motion is f _{d _ i} . Then the target reflection signal can be expressed as:

；

;

Wherein A _{i_R} ( i =- M ,- M +1,..., M ) is the sub-signal amplitude of the target reflected signal. The output signal of the optical 90° optical mixer of the coherent receiving unit can be expressed as:

；

;

Among them, S _{I +} ( t ), S _{I -} ( t ), S _{Q +} ( t ), S _{Q -} ( t ) are the four optical signals output by the 90-degree optical coupler, and the output of the 90-degree optical coupler The four optical signals are respectively sent to two balanced photodetectors to complete the photoelectric conversion, ignoring the parasitic phase, the intermediate frequency electrical signal output by the coherent detection unit can be expressed as:

；

;

为中频信号的相位信息，对应信号复数形式为：That is, two orthogonal components S _I ( t ) and S _Q ( t ) of the intermediate frequency signal carrying target information, where

is the phase information of the intermediate frequency signal, and the complex number form of the corresponding signal is:

；

;

Where A _{R_i} is the amplitude of the intermediate frequency electric signal of the sub-signal, and the complex intermediate frequency signal carrying the target information is located in the interval [( m -1/2) ∙ ∆ f _PFR , ( m +1/2) ∙ ∆ f _PFR ] , where m =-M, -M+1,...,M-1,M; M is the number of single-sided optical frequency comb teeth, ∆ f _PFR =|∆ f _PFR1 -∆ f _PFR2 | is the repetition frequency difference of the dual optical frequency combs, the signal is collected, and the channel angle mapping and distance information extraction are performed to obtain the target angle, distance two-dimensional spatial distribution and velocity information in the θ plane. Then adjust the phase difference ∆ ϕ between adjacent channels through the phase shifter array, and use the mapping relationship between the phase difference ∆ ϕ and the scanning angle ϕ _O to realize scanning in the dimension perpendicular to the θ plane direction, and through signal reorganization and processing, that is It can realize the acquisition of target three-dimensional spatial distribution and velocity information.

In summary, the present invention provides a three-dimensional solid-state laser radar chip and its detection method and system, based on the optical frequency comb dispersion mechanism and phase shifter array phase control, to realize simultaneous scanning of laser radar in two dimensions, combined with frequency-modulated continuous wave Radar detection technology and coherent reception realize the acquisition of high-resolution target distance and speed information. Based on two optical frequency comb difference frequency multiplexing and coherent detection technology, two detectors can realize simultaneous reception of all channel data. Based on III- V-group device chips and silicon photonic chips are monolithically integrated to realize monolithic integration of LiDAR. The whole system is pure solid state, without mechanical scanning to control the beam direction, the system structure is simple and compact, and can be integrated.

The above description is only a preferred embodiment of the present invention, and is not intended to limit the present invention. Any modification, equivalent replacement or improvement made within the spirit and principles of the present invention shall be included in the protection of the present invention. within range.

Claims (9)

1. A three-dimensional solid-state laser radar chip is characterized in that: the grating optical coupler comprises a laser, a first optical coupler, a first micro-ring resonant cavity, a second micro-ring resonant cavity, a first optical amplifier, a second optical coupler, a 90-degree optical mixer, a first balanced detector, a second balanced detector, a 1 xN power divider, a phase shifter array and a grating antenna array, wherein all photonic components are connected through optical waveguides;

the output end of the laser is connected with the input end of a first optical coupler, the output end of the first optical coupler is respectively connected with a first micro-ring resonant cavity and a second micro-ring resonant cavity with different radius sizes, the output ends of the first micro-ring resonant cavity and the second micro-ring resonant cavity are respectively connected with the input ends of a first optical amplifier and a second optical amplifier, the output ends of the first optical amplifier and the second optical amplifier are respectively connected with one port of the second optical coupler and one input end of a 90-degree optical mixer, the other two ports of the second optical coupler are respectively connected with the input end of a 1 x N power divider and the other input end of the 90-degree optical mixer, N output ends of the 1 x N power divider are connected with N input ends of a phase shifter array, N output ends of the phase shifter array are connected with N input ends of a grating antenna array, and four output ends of the 90-degree optical mixer are respectively connected with the input ends of a first balance detector and a second balance detector.

2. The three-dimensional solid-state lidar chip of claim 1, wherein: the laser, the first optical amplifier and the second optical amplifier are made of materials which can be integrated with a silicon optical chip, and the materials comprise indium phosphide, gallium arsenide and gallium nitride which are prepared based on a III-V group process platform.

3. The three-dimensional solid-state lidar chip of claim 1, wherein: the first micro-ring resonant cavity, the second micro-ring resonant cavity, the first optical coupler, the second optical coupler, the 90-degree optical mixer, the 1 xN power divider, the phase shifter array, the grating antenna array, the first balanced detector and the second balanced detector are devices prepared on the basis of a silicon optical process platform.

4. The three-dimensional solid-state lidar chip of claim 1, wherein: the first micro-ring resonant cavity and the second micro-ring resonant cavity are used for exciting a linear frequency modulation signal output by the laser to form a plurality of comb-shaped sidebands by generating dissipative Kerr solitons to generate a linear frequency-sweeping optical frequency comb signal; the radius sizes of the micro-rings of the first micro-ring resonant cavity and the second micro-ring resonant cavity are different and respectively correspond to different optical frequency comb repetition frequencies.

5. The three-dimensional solid-state lidar chip of claim 1, wherein: the frequency response of the first balanced detector pair and the second balanced detector pair covers all intermediate frequency signals of the laser radar.

6. A detection method based on the three-dimensional solid-state laser radar chip of any one of claims 1 to 5, characterized in that: the method comprises the following steps:

step 1, a laser generates a linear frequency-modulated optical signal and sends the linear frequency-modulated optical signal to an input end of a first optical coupler, and the first optical coupler divides the optical signal into two paths and sends the two paths of optical signals to a first micro-ring resonant cavity and a second micro-ring resonant cavity respectively;

step 2, exciting the first micro-ring resonant cavity by a linear frequency modulated optical signal to generate a linearly swept detection optical frequency comb signal, exciting the second micro-ring resonant cavity to generate a linearly swept reference optical frequency comb signal, and respectively sending the detection optical frequency comb signal and the reference optical frequency comb signal to a first optical amplifier and a second optical amplifier for amplification; the amplified detection optical frequency comb signal is sent to the 1 XN power divider through the second optical coupler, and the amplified reference optical frequency comb signal is sent to the 90-degree optical mixer;

step 3, the 1 xN power divider equally divides the amplified detection optical frequency comb signals into N paths, the N paths of detection optical frequency comb signals are respectively sent into N phase shifter arrays from the output end of the 1 xN power divider, the phase shifter arrays carry out phase control on the N paths of detection optical frequency comb signals, the N paths of detection optical frequency comb signals with the phase control are sent into the input end of the N grating antenna arrays from the N output ends of the phase shifter arrays, and the detection optical signals are radiated into space through the grating antenna arrays;

step 4, the detection optical signal is reflected back to the grating antenna array after encountering the target to obtain a received optical signal, the received optical signal is sent to the phase shifter array through the grating antenna array, sent to N ports of the 1 xN power divider through the phase shifter array, and sent to the 90-degree optical mixer through the second optical coupler;

and 5, the received light signal and the reference light signal enter a first balanced detector and a second balanced detector to complete coherent detection to obtain a complex intermediate frequency signal carrying target information, and after the complex intermediate frequency signal is subjected to signal acquisition, the target three-dimensional spatial distribution and speed information are obtained based on a radar signal algorithm.

7. The detection method of claim 6, wherein: in the step 1, the chirp method for generating the chirped optical signal by the laser includes, but is not limited to, a sawtooth chirp, a triangular chirp, and a piecewise chirp.

8. The detection method of claim 6, wherein: in step 3, a single grating antenna in the grating antenna array controls different comb-tooth frequency-sweep sub-signal beams of the detection optical signal to point to 2m +1 different directions on the theta plane based on frequency dispersion, wherein M is the number of comb teeth of the single-side optical frequency comb, so that 2m +1 detection sub-optical signals pointing to different directions are obtained, scanning of the optical beam on the theta plane is achieved, and scanning of the optical beam on the other dimension perpendicular to the theta plane is achieved by adjusting and controlling the phase of an adjacent channel of the phase shifter array.

9. A detection system based on the three-dimensional solid-state lidar chip of any of claims 1-5, wherein: the system comprises the three-dimensional solid-state laser radar chip and a signal acquisition and processing unit, wherein the signal acquisition and processing unit is connected with the radio frequency output ends of a first balanced detector and a second balanced detector in the three-dimensional solid-state laser radar chip;

the three-dimensional solid laser radar chip is used for realizing simultaneous scanning of a target by a laser radar in two dimensions based on an optical frequency comb dispersion mechanism and phase regulation and control of a phase shifter array; the signal acquisition and processing unit is used for acquiring and processing target information obtained by scanning the three-dimensional solid laser radar chip and realizing target distance, position and speed information acquisition by combining frequency modulation continuous wave radar detection technology and coherent reception.

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