Single-photon ranging signal processing device and method for long-distance high-speed moving target

Abstract

The invention discloses a single-photon ranging signal processing device for a long-distance high-speed moving target, and the device comprises a detector and a signal processing module which is connected with the detector through a detector level conversion circuit and an RS232 interface circuit. The signal processing module is formed by connecting a ZYNQ chip serving as a master processing chip and a plurality of ZYNQ chips serving as slave processing chips, and each of the rest slave processing chips is responsible for processing data of different distance segments; the ZYNQ chip comprises an echo signal timing module, a DDR interface module, a parallel parameter matching module, a parameter matching peak search module and a DDR read address generation module which are connected in sequence; the invention further discloses a treatment method. According to the invention, single-photon ranging echo signal processing of a long-distance high-speed moving target is realized on the ZYNQ chip, the whole distance range can be searched in one sampling, the time for measuring the target is greatly shortened, and the real-time performance is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of single photon ranging, and in particular to a single photon ranging signal processing device and method for long-distance high-speed moving targets, which are used to realize the collection and real-time processing of single photon detector echo signals. Background Art

[0002] With the improvement of science and technology, the application of long-range ranging in terrain survey, satellite launch, etc. is gradually increasing. Compared with traditional lidar, the high repetition rate and low pulse energy detection mechanism adopted by photon counting radar increases its laser echo rate by more than two orders of magnitude compared with traditional lidar systems, which enables photon counting lidar systems to obtain higher sampling rates and detection accuracy.

[0003] This also allows the lidar system to use a smaller telescope aperture, helping to reduce the weight and volume of the system and reduce system power consumption.

[0004] In terms of photon echo signal detection, the photon counting radar system uses a highly sensitive single photon detector and adopts a direct detection method. This detection method is based on the TOF (Time of Flight) mode and obtains the relative distance of the target by measuring the flight time of photons.

[0005] Long-distance single-photon detection of small targets in complex high-speed motion has great practical significance. Small targets in high-speed motion have lower signal-to-noise ratios, and high-speed motion also has a great impact on the accumulation of photon events, all of which pose greater challenges to the processing of echo signals. In addition, in order to improve the real-time response, it is necessary to search a wide range of distances at the same time, which requires a lot of computing and storage resources, which is not conducive to miniaturization. Summary of the invention

[0006] One of the purposes of the present invention is to overcome the above-mentioned shortcomings and provide a small single-photon ranging signal processing device for long-distance high-speed moving targets. The device has a long search distance and can adapt to high-speed moving targets by performing parameter matching in the speed-starting distance space. The adaptive calculation threshold can better adapt to a variety of noise environments. The device has a high degree of integration and realizes the collection and real-time processing of single-photon ranging signals.

[0007] The technical solution adopted by the present invention to solve its technical problems is: a single-photon ranging signal processing device for long-distance high-speed moving targets, including a detector and a signal processing module connected to the detector through a detector level conversion circuit and an RS232 interface circuit, the signal processing module is composed of a ZYNQ chip as a main processing chip and multiple ZYNQ chips as slave processing chips, and each of the remaining slave processing chips is responsible for processing data of different distance segments; the ZYNQ chip includes an echo signal timing module, a DDR interface module, a parallel parameter matching module, a parameter matching peak search module and a DDR read address generation module connected in sequence, the parameter matching peak search module is simultaneously connected to the inter-chip interface module and the DDR read address generation module, the DDR read address generation module is connected to the DDR interface module, and the parallel parameter matching module The block includes a parameter distribution module and multiple parameter matching sub-modules composed of a spatial mapping module and a histogram statistics module. The ZYNQ chip as the main processing chip also includes a detector interface module connecting the detector and the inter-chip interface module and the echo signal timing module. The inter-chip interface module of the ZYNQ chip as the slave processing chip is connected to the echo signal timing module. Two adjacent ZYNQ chips are connected through the inter-chip interface module. The ZYNQ chip as the main processing chip also includes a PL-PS communication module connected to the parallel parameter matching module and the parameter matching peak search module and an external communication module connected to the parameter matching peak search module. The PL-PS communication module is connected to the threshold calculation module. The external communication module is connected to the host computer through the RS422 interface circuit. The DDR interface module and the parallel parameter matching module are connected to the DDR chip and the FLASH chip respectively.

[0008] A second object of the present invention is to provide an echo signal processing method of a single photon ranging signal processing device, comprising the following steps: The laser emits laser to the moving target, and generates an echo signal when it hits the object. The trigger signal and echo signal output by the detector are converted by the detector level conversion circuit and then input into the detector interface module of the ZYNQ chip which is the main processing chip. After that, the signal is divided into two paths. One path is input into the ZYNQ chip as the slave processing chip through the master-chip interface module, and the other path is input into the echo signal timing module. After the echo signal is timed by high-frequency clock sampling, the time information and the repetition sequence information are stored in the off-chip DDR chip through the DDR interface module for cache. The DDR read address generation module generates a DDR read address and a read request according to the parameters provided by the parameter matching peak search module. The read data is matched with parameters in the local speed-starting distance space by the various parameter matching submodules of the parallel parameter matching module, and the cumulative parameter matching peak value is obtained by histogram statistics of the results. The local matching peak value is output to the parameter matching peak search module. The parameter matching peak search module searches in the global range to find the global maximum matching peak value of the distance segment. The parameter distribution module is responsible for distributing the corresponding local speed and other parameters to each parameter matching submodule. The parameter matching peak search module performs a secondary global search on the maximum matching peak of the main processing chip ZYNQ chip and the maximum matching peak of the slave processing chip ZYNQ chip 4 transmitted through the main chip interface module to obtain the global maximum matching peak of the entire distance segment, and compares it with the threshold to calculate the final distance measurement result; Furthermore, the ZYNQ chip simultaneously sets the repetition sequence number counter n to 0, and in synchronization with the trigger signal output by the detector, the repetition sequence number counter n is incremented by 1, and the fused echo signal is sampled using a high-frequency clock to obtain the time difference between the echo signal and the trigger signal. , the time difference and the distance s corresponding to the echo signal have the following corresponding relationship: , where c represents the speed of light; then the distance s of the echo signal and the corresponding repetition sequence number n are sent to the DDR interface module for storage until the value of the repetition sequence number counter n is equal to the set accumulation number parameter N, then the collection of the current frame data is completed.

[0009] Furthermore, the distance segment that each ZYNQ chip is responsible for is divided into multiple sub-distance segments, which are processed one by one within a frame period; the storage space is divided into several sub-areas according to the address, and the distance is divided into one-fourth of the sub-distance segment. The echo signal corresponding to each quarter of the sub-distance segment is stored in the corresponding sub-area, and the idle area is filled with a value representing invalid data.

[0010] Furthermore, the peak accumulation method based on parameter matching in the velocity (v)-starting distance (k) space is used to extract the target echo signal: This method is essentially a Hough transform. Assuming that the object's moving speed remains unchanged during a measurement, we have , where T n Represents the time when the nth repetition frequency sequence distance measurement starts, specifically , where f represents the laser repetition frequency, after deformation, we get According to the formula, the k corresponding to each echo signal (s, T_n) under a specific v can be calculated. Note that the starting distance here is the relative distance relative to the starting point of the distance segment.

[0011] Compared with the prior art, the present invention has the following beneficial effects: The present invention realizes the single-photon ranging echo signal processing of long-distance and high-speed moving targets on the ZYNQ chip, and can simultaneously search the entire distance range in one sampling, which greatly shortens the time of measuring the target and improves the real-time performance.

[0012] The present invention solves the problem of poor high-speed moving target extraction effect by performing parameter matching in the speed-starting distance space, and effectively reduces the resource consumption of parameter space matching; the threshold is adaptively calculated according to the received data, which can better adapt to various noise environments and expand the scope of application of the device. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is a structural schematic diagram of the present invention; Figure 2 This is a schematic diagram of the storage area division of the present invention; Figure 3 A schematic diagram of parameter space search in the parameter matching process of the present invention; Figure 4 This is a partial point cloud diagram of the simulated echo signal of a moving target at 600m / s under low signal-to-noise ratio; Figure 5 The peak diagram of algorithm parameter matching for a 600m / s moving target under low signal-to-noise ratio; Figure 6 This is a diagram of the ping-pong operation of the DDR chip.

[0014] The figures are marked as follows: 1—detector, 2—detector level conversion circuit, 3—RS232 interface circuit, 4—ZYNQ chip, 40—detector interface module, 41—inter-chip interface module, 42—echo signal timing module, 43—DDR interface module, 44—parallel parameter matching module, 441—parameter distribution module, 442—parameter matching submodule, 45—parameter matching peak search module, 46—DDR read address generation module, 47—PL-PS communication module, 48—external communication module, 5—RS422 interface circuit, 6—threshold calculation module, 7—host computer, 8—DDR chip, 9—FLASH chip. DETAILED DESCRIPTION

[0015] In order to better understand the present invention, the content of the present invention is further explained below in conjunction with the drawings and specific embodiments.

[0016] Reference Figure 1As shown, the present invention discloses a small single-photon ranging signal processing device for long-distance high-speed moving targets, including a detector 1 and a signal processing module connected to the detector 1 through a detector level conversion circuit 2 and an RS232 interface circuit 3. The signal processing module is composed of a ZYNQ chip 4 as a main processing chip and multiple ZYNQ chips 4 as slave processing chips and peripheral connections. Each of the remaining slave processing chips is responsible for processing data in different distance segments.

[0017] The ZYNQ chip 4 serving as the main processing chip PL includes a detector interface module 40, a main chip interface module 41, an echo signal timing module 42, a DDR interface module 43, a DDR read address generation module 46, a parallel parameter matching module 44 (including a parameter distribution module 441 and a parameter matching submodule 442 consisting of a spatial mapping module and a histogram statistics module), a PL-PS communication module 47, an external communication module 48 and a parameter matching peak search module 45, and the processing system (Processing System, abbreviated as PS) includes a threshold calculation module 6, and the threshold calculation module 6 is connected to the PL-PS communication module 47.

[0018] The ZYNQ chip 4 as a slave processing chip only uses the PL part, including a slave chip interface module 41, an echo signal timing module 42, a DDR interface module 43, a DDR read address generation module 46, a parallel parameter matching module 44 (including a parameter distribution module 441 and a parameter matching submodule 442 composed of a spatial mapping module and a histogram statistics module) and a parameter matching peak search module 45. Except for the slave chip interface module 41, the remaining modules are logically the same as the corresponding modules of the main processing chip, and only the configured parameters are different.

[0019] Two adjacent ZYNQ chips 4 are connected via two master-slave inter-chip interface modules 41. The peripheral device of the present invention comprises a flash memory Flash chip 9 and a double rate synchronous dynamic random access memory (DDRSDRAM) DDR chip 8; a detector level conversion circuit 2, an RS232 interface circuit 3 and an RS422 interface circuit 5 constitute the external interface circuit of the present invention.

[0020] The method for processing the single-photon ranging detector echo signal using the above-mentioned single-photon ranging signal processing device for long-distance high-speed moving targets includes the following steps.

[0021] The laser emits a laser to a moving target, and generates an echo signal when it hits the object. The trigger signal and the echo signal output by the detector 1 are converted in level by the detector level conversion circuit 2 and then input into the detector interface module 40 of the ZYNQ chip 4 as the main processing chip; then the signal is divided into two paths, one path is input into the ZYNQ chip 4 as the slave processing chip through the main chip interface module 41, and the other path is input into the echo signal timing module 42. After the echo signal is timed by high-frequency clock sampling, the time information and the repetition sequence information are stored in the off-chip DDR chip 8 through the DDR interface module 43 for caching; the DDR read address generation module 46 generates a DDR read address and a read request according to the parameters provided by the parameter matching peak search module 45, and the read data is locally matched by each parameter matching submodule 442 of the parallel parameter matching module 44. Parameter matching in the speed-starting distance space is performed, and the results are histogrammed to obtain the cumulative parameter matching peak value, and the local matching peak value is output to the parameter matching peak search module 45, which searches in a global range to find the global maximum matching peak value of this distance segment (obtained by the time when the measured moving target and the echo signal are generated); the parameter distribution module 441 is responsible for distributing the corresponding local speed and other parameters to each parameter matching sub-module 442; the parameter matching peak search module 45 performs a secondary global search on the maximum matching peak value of the main processing chip ZYNQ chip 4 and the maximum matching peak value of the slave processing chip ZYNQ chip 4 transmitted through the main chip interface module 41 to obtain the global maximum matching peak value of the entire distance segment, and compares it with the threshold to calculate the final ranging result; the final ranging result is transmitted to the host computer 7 through the external communication module 48.

[0022] The PL-PS communication module 47 transmits the local parameter-matched histogram statistical data to the PS for calculating the adaptive threshold in the threshold calculation module 6 on the PS, and transmits the obtained threshold back to the parameter matching peak search module 45 .

[0023] The further steps of the device of the present invention when performing signal processing are as follows.

[0024] (1) After the ranging signal processing device loads the program through the FLASH chip 9, all internal registers are cleared, and the detector interface module 40 configures the detector 1 through the serial port. The multi-channel echo signals of the array of the detector 1 are fused, and if the sum of the response numbers of each channel exceeds the threshold, the input signal is determined to be valid, thereby improving the signal-to-noise ratio of the input signal.

[0025] (2) ZYNQ chip 4, which serves as the main processing chip PL, starts the acquisition work after receiving the start command sent by the host computer 7, and sets the repetition sequence number counter n to 0; under the synchronization of the trigger signal output by the detector 1, the repetition sequence number counter n is increased by 1, and the fused echo signal is sampled using a high-frequency clock to obtain the time difference between the echo signal and the trigger signal. , the time difference and the distance s corresponding to the echo signal have the following corresponding relationship: , where c represents the speed of light. Then the distance s of the echo signal and the corresponding repetition sequence number n are sent to the DDR interface module 43 for storage. The acquisition of the current frame data is completed until the value of the repetition sequence number counter n is equal to the set accumulation number parameter N.

[0026] Due to the resource limitation of ZYNQ chip 4, the entire distance range cannot be processed simultaneously in one calculation process. To solve this problem, on the one hand, multiple ZYNQ chips 4 are used to form a master-slave structure for parallel processing. On the other hand, the distance segment that each ZYNQ chip 4 is responsible for is divided into multiple sub-distance segments, which are processed one by one in one frame cycle. In order to avoid missed detection due to moving targets crossing sub-distance segments, there are overlapping areas when the sub-distance segments are divided. Combined with the storage characteristics of DDR chip 8, in order to facilitate address jumps during reading, the storage area is divided into multiple sub-distance segments. Figure 2 As shown in the figure: the storage space is divided into several sub-areas by address (divided by 32 addresses in the example), and the distance is divided by one-fourth of the sub-range segment (375m in the example). The echo signal corresponding to each quarter of the sub-range segment is stored in the corresponding sub-area, and the free area is filled with the value representing invalid data. Due to the limitation of the dead time of detector 1, it is guaranteed that the amount of data of one-fourth of the sub-range segment will not occupy more than one sub-area address. The data of the next sequence is stored after the address of the last sub-range segment of the previous sequence.

[0027] (3) After a frame of data is collected and stored in the DDR chip 8, the ZYNQ chip 4 starts to read the data. Since the speed parameter space range and the distance range in the parameter matching are too large, it is impossible to search the entire parameter and distance space at one time. Therefore, the parameter matching peak search module 45 controls the distance and parameter range of each search, and generates the corresponding DDR read address and read request according to the current range control. The specific search method is as follows: Figure 3 As shown, the search is performed in the speed space first and then in the distance space. During each search, the data of the corresponding addresses of all sequences in the distance segment are read out respectively.

[0028] Figure 4 The figure shows the simulated point cloud of the echo signal of a moving target at 600 m / s under low signal-to-noise ratio. The red box is the target trajectory. Figure 4As shown, for high-speed moving targets, especially those in low signal-to-noise ratio environments, the effect of extracting the target motion trajectory by simply relying on the cumulative number of photon events within the distance grid is very poor. In order to solve the problem of difficulty in extracting the target echo signal of single-photon ranging of high-speed and long-distance moving targets, a peak accumulation method based on parameter matching is adopted, and each parameter matching submodule 442 is responsible for the parameter matching of a speed parameter. This method is essentially a Hough transform. Since the sampling time is very short, the change in target speed during this period has little effect on the accumulation of parameter space, so it can be regarded as uniform motion. Considering that the Hough transform parameter space has two problems for this application if the angle and polar radius are selected: Since this application uses hundreds of parallel sub-modules to perform parameter matching calculations simultaneously, the resources occupied by trigonometric function calculations during the matching process cannot be ignored.

[0029] After the velocity is mapped to the angle, it is no longer evenly distributed. Because there is an upper limit to the object's velocity, this application uses the velocity (v)-starting distance (k) space. Assuming that the object's velocity remains constant during a measurement, we have , where T n Represents the time when the nth repetition frequency sequence distance measurement starts, specifically , where f represents the laser repetition frequency, after deformation: According to the formula, the value of each echo signal (s, T n ) corresponding to k. Note that the starting distance here is the relative distance to the starting point of the distance segment.

[0030] (4) Perform histogram statistics on the obtained starting distance k to obtain the cumulative peak value after parameter matching. Figure 5 The figure shows the algorithm parameter matching peak diagram of a 600m / s moving target under low signal-to-noise ratio. The red box is the maximum matching peak. Figure 5 As shown in the figure, after parameter matching, the parameter area corresponding to the target trajectory has an obvious peak, which can be clearly distinguished from the background noise. Note that due to the movement of the object, the k calculated for the object at the edge will exceed the spatial range. Because the detection of these objects will be handled by another overlapping distance segment, they are discarded. Then find and record the maximum value of the histogram of the submodule, and record the corresponding v and k. Traverse all parallel modules to find and record the local maximum matching peak under the current distance segment and speed range and record the corresponding v and k.

[0031] (5) Traverse the next velocity space and distance segment parameters and repeat steps (3) to (4) until all distance segments and velocity spaces are traversed. Find and record the global maximum matching peak and record the corresponding v and k.

[0032] (6) The histogram obtained by parameter space statistics when the speed of the first distance segment is 0 is written into the DDR of the PS plug-in through the AXI4 protocol, and then the PS reads the histogram to estimate the background noise.

[0033] Specifically, firstly, the mean of the histogram amplitude is calculated respectively. With standard deviation . Then we have: , where TH is the adaptive matching peak threshold, A is the preset noise threshold, when it is lower than this threshold, it is considered to be a low noise background, and the matching peak threshold is set to a fixed value B, otherwise it is adaptively set according to the mean and standard deviation of the noise.

[0034] (7) Compare the global maximum matching peak with the matching peak threshold. If it reaches the threshold, it is considered to be a target and the corresponding distance information is output. Otherwise, it is considered to be background. Because the background noise level will not change dramatically in a short period of time, in order to ensure real-time performance, the matching peak threshold calculated from the previous frame of acquisition data is used for each comparison.

[0035] (8) Repeat steps (3) to (7) to perform a new signal processing.

[0036] Figure 6 The diagram shows the ping-pong operation of the DDR chip 8: (a) is an odd cycle, and (b) is an even cycle. Figure 6 As shown, in order to improve the data processing speed of the device, the device uses the echo signal acquisition and distance calculation as the two stages of the pipeline, and accelerates in a pipeline manner. At the same time, the DDRSDRAM spectrum storage area is divided into two areas for ping-pong operation. While using the data collected in the previous cycle for calculation, the current frame data is collected and stored in another area to avoid conflicts in data reading and storage in different cycles.

[0037] The repetition frequency of the laser used in this embodiment is 5KHz, and the frequency of ranging is 20Hz, that is, the number of accumulations is 250, and the overall measurement distance is 50m to 30000m. The processing chip used in the embodiment is XC7Z100FFG900-2 of the Zynq7000 series.

[0038] The device described in the embodiment adopts two ZYNQ chips 4 for parallel processing, the master chip is responsible for the target measurement within the distance range of 50m to 16125m, the slave chip is responsible for the target measurement within the distance range of 13875m to 30000m, and the distance range responsible for each chip is divided into 43 sub-areas, each sub-area is 375m away, the corresponding sub-distance segment is 1500m, and every two adjacent sub-distance segments overlap by 375m. The search target motion speed range is about ±3400m / s, and the speed step is about 3m / s. Each processing chip instantiates 455 parameter matching submodules, which can simultaneously search the speed parameter space within a sub-distance segment of about 1365m / s. The search of the parameter space within a sub-distance segment can be completed after 5 traversals.

[0039] The system of the embodiment collects echo signals generated by 250 pulses for distance measurement once, searches for the maximum value of the accumulated peak within the global parameter space, and compares it with the threshold value calculated by the threshold calculation module 6. If it is higher than the threshold value, it is considered to be a target, otherwise it is considered to be noise. Finally, the result is transmitted to the host computer 7 through the serial port.

[0040] Experiments show that the present invention can meet the needs of collecting and real-time processing single-photon ranging echo signals of long-distance, high-speed moving targets. It can search the entire distance range simultaneously in one sampling with good real-time performance. The extraction effect of high-speed moving targets is greatly improved through parameter matching, and the adaptive calculation threshold greatly improves the working performance of the device in complex noise environments.

Claims

1. A single photon ranging signal processing device for a long-distance high-speed moving target, characterized in that: The invention comprises a detector (1) and a signal processing module connected to the detector (1) via a detector level conversion circuit (2) and an RS232 interface circuit (3); the signal processing module is composed of a ZYNQ chip (4) as a master processing chip and a plurality of ZYNQ chips (4) as slave processing chips; the ZYNQ chip (4) comprises an echo signal timing module (42), a DDR interface module (43), a parallel parameter matching module (44), a parameter matching peak search module (45) and a DDR read address generation module (46) connected in sequence; the parameter matching peak search module (45) is simultaneously connected to an inter-chip interface module (41) and a DDR read address generation module (46); the DDR read address generation module (46) is connected to the DDR interface module (43); the parallel parameter matching module (44) comprises a parameter distribution module (441) and a plurality of modules composed of a space mapping module and a histogram statistics module. The ZYNQ chip (4) as the main processing chip further comprises a detector interface module (40) connecting the detector (1) with the inter-chip interface module (41) and the echo signal timing module (42); two adjacent ZYNQ chips (4) are connected via the inter-chip interface module (41); the ZYNQ chip (4) as the main processing chip further comprises a PL-PS communication module (47) connected to the parallel parameter matching module (44) and the parameter matching peak search module (45) and an external communication module (48) connected to the parameter matching peak search module (45); the PL-PS communication module (47) is connected to the threshold calculation module (6); the external communication module (48) is connected to the host computer (7) via the RS422 interface circuit (5); the DDR interface module (43) and the parallel parameter matching module (44) are connected to the DDR chip (8) and the FLASH chip (9) respectively.

2. An echo signal processing method of the single photon ranging signal processing device as claimed in claim 1, characterized in that: The steps include: The laser emits laser light to a moving target, and generates an echo signal when it hits the object. The trigger signal and the echo signal output by the detector (1) are converted into levels by the detector level conversion circuit (2) and then input into the detector interface module (40) of the ZYNQ chip (4) serving as the main processing chip. The signal is then divided into two paths, one path is input into the ZYNQ chip (4) as a slave processing chip through the master-chip interface module (41), and the other path is input into the echo signal timing module (42). After the echo signal is timed by high-frequency clock sampling, the time information and the repetition sequence information are stored in the off-chip DDR chip (8) through the DDR interface module (43); The DDR read address generation module (46) generates a DDR read address and a read request according to the parameters provided by the parameter matching peak search module (45). The read data is matched with parameters in a local speed-starting distance space by the parameter matching submodule (442), and the result is statistically analyzed in a histogram to obtain a cumulative parameter matching peak value. The local matching peak value is output to the parameter matching peak search module (45). The parameter matching peak search module (45) searches in a global range to find the global maximum matching peak value of the distance segment. The parameter distribution module (441) distributes the corresponding local speed to each parameter matching submodule (442). The parameter matching peak search module (45) performs a secondary global search on the maximum matching peak of the main processing chip ZYNQ chip (4) and the maximum matching peak of the slave processing chip ZYNQ chip 4 transmitted through the main chip interface module (41) to obtain the global maximum matching peak of the entire distance segment, and compares it with the threshold value to obtain the final distance measurement result; The final distance measurement result is transmitted to the host computer (7) through the external communication module (48).

3. The echo signal processing method of the single photon ranging signal processing device according to claim 2, characterized in that: The ZYNQ chip (4) simultaneously sets the repetition sequence number counter n to 0, and in synchronization with the trigger signal output by the detector (1), the repetition sequence number counter n is incremented by 1, and the fused echo signal is sampled using a high-frequency clock to obtain the time difference between the echo signal and the trigger signal. , the time difference and the distance s corresponding to the echo signal have the following corresponding relationship: , where c represents the speed of light; Then, the distance s of the echo signal and the corresponding repetition sequence number n are sent to the DDR interface module (43) for storage, until the value of the repetition sequence number counter n is equal to the set accumulation number parameter N, and the collection of the current frame data is completed.

4. The echo signal processing method of the single photon ranging signal processing device according to claim 2 or 3, characterized in that: The distance segment that each ZYNQ chip (4) is responsible for is divided into a plurality of sub-distance segments, which are processed one by one in a frame cycle; the storage space is divided into a plurality of sub-areas according to the address, and the distance is divided into a quarter of the sub-distance segment, and the echo signal corresponding to each quarter of the sub-distance segment is stored in the corresponding sub-area, and the idle area is filled with a value representing invalid data.

5. The echo signal processing method of the single photon ranging signal processing device according to claim 2 or 3, characterized in that: The target echo signal is extracted by using the peak accumulation method based on parameter matching in the velocity (v)-starting distance (k) space: Assuming that the object's moving speed remains unchanged during a measurement, then , where T n Represents the time when the nth repetition frequency sequence distance measurement starts, specifically , where f represents the laser repetition frequency, after deformation, we get , according to the formula, calculate the k corresponding to each echo signal (s, T_n) under a specific v.

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