A method and system for laser radar ranging and communication based on dual pulse separation

Abstract

The application discloses a kind of method and system for laser radar ranging based on double pulse interval and communication, belong to the technical field of instruments and apparatus, including signal processing module, signal transmitting module, signal receiving module and signal measurement module;The application combines pulse ranging and pulse communication, realizes communication effect while realizing distance measurement, improves system integration degree;Radar IP is added using FPGA, monostable trigger is used to generate time window signal, TDC is used to measure signal spacing, and the device cost is lower;Part of irrelevant signal is shielded using time window at receiving end, and the anti-interference ability of communication is improved;Radar IP based on double pulse interval is used to prevent external interference and further improve the anti-interference ability of ranging and communication.The method and circuit realize communication while identifying and distance measuring the signal object, and have certain practical value in various radar communication occasions.

Description

Technical Field

[0001] This invention belongs to the field of instrumentation technology, specifically relating to a method and system for laser radar ranging and communication based on a dual-pulse interval. Background Technology

[0002] Due to its advantages such as high stability and high brightness, lasers are widely used in ranging systems. Meanwhile, with the rapid development of autonomous driving technology, lidar, with its strong scanning performance and fast imaging speed, has achieved significant breakthroughs as a key component and will become a standard accessory in automobiles. Multiple lidar units will likely coexist in the same application scenario, making the realization of multi-liquidity communication and ranging a pressing issue that needs to be addressed. Summary of the Invention

[0003] To address the problems of limited functionality and weak anti-interference capabilities in existing technologies, this invention proposes a method and system for lidar ranging and communication based on dual-pulse intervals. Different pulse intervals correspond to different transmitting radars or signals, and a time window is used at the receiving end to shield irrelevant signals. This method and circuit can identify the transmitting target and measure the distance while achieving communication, and have certain practical value in various radar communication scenarios.

[0004] This invention is achieved through the following technical solution:

[0005] A system for ranging and communication using a double-pulse interval lidar includes a signal processing module, a signal transmitting module, a signal receiving module, and a signal measurement module. The signal processing module converts binary data into double-pulse intervals of a specific length and sends them to the signal transmitting module, which converts them into corresponding double-pulse laser signals. Part of the laser signal is reflected at the communication target and received by the transmitting radar to achieve ranging, while the other part is directly received by the receiving radar to achieve communication. The signal measurement module measures the double-pulse signal transmitted from the signal receiving module, calculates the flight time of the double-pulse signal, and then sends it back to the signal processing module.

[0006] Furthermore, the signal processing module includes a microcontroller 1 and a field-programmable gate array (FPGA) 2. The microcontroller 1 is used to transmit communication content and local IP information to the FPGA 2. The FPGA 2 is used to convert the signal into an interval length within a specified range and send the pulse interval control signal to the dual-pulse generation circuit of the signal transmission module.

[0007] Further, the FPGA2 includes an interval encoding module 10, a pulse control module 14, a distance calculation module 11, a TDC control module 15, an interval decoding module 12, and a delay module 13. The interval encoding module 12 outputs a corresponding interval based on the communication content and its own radar IP information, which is then transmitted to the pulse control module 14 and converted into a pulse interval control signal required by the dual-pulse generation circuit 3 of the control signal transmission module. The TDC control module 15 controls the signal measurement module, transmitting control signals to the signal measurement module and simultaneously receiving measurement signals from the signal measurement module. The measurement signals are determined according to the communication content and its own radar IP information. The signals can be divided into dual-pulse interval measurement signals and distance signals. The distance signal is sent to the distance calculation module 11, and the dual-pulse interval measurement signal is sent to the interval decoding module 10. After receiving the distance signal, the distance calculation module 11 calculates the communication distance and then sends it to the microcontroller 1. The interval decoding module 10 is used to decode the radar IP signal and communication signal contained in the dual-pulse interval measurement signal and send them to the microcontroller 1. The delay module 13 is used to perform corresponding extension operations on the time window signal sent by the dual-pulse interval measurement module 5 according to the instructions of the microcontroller 1, so as to adjust the width of the time window.

[0008] Furthermore, the signal transmitting module includes a dual-pulse generating circuit 3, an LD driving circuit 6, and an LD8. The dual-pulse generating circuit 3 is used to receive the pulse interval control signal from the pulse control module 16 in the FPGA2, convert the pulse interval control signal from digital to the corresponding current signal, and send one signal to the TDC4 and the other signal to the LD driving circuit 6 to form the driving current required by the LD8. Finally, the LD8 emits a laser signal under the drive of the driving current.

[0009] Furthermore, the signal receiving module includes an avalanche photodiode (APD9), a transimpedance amplifier circuit 7, and a dual-pulse interval measurement module 5. The APD9 receives laser signals from the air and converts them into electrical signals. These signals are amplified by the transimpedance amplifier circuit 7, and the output signal is sent to the Stop1 channel of the TDC4 to measure the flight time of the echo signal. The other output signal is sent to the dual-pulse interval measurement module 5 to measure the dual-pulse interval. The dual-pulse interval measurement module 5 is used to separate the dual-pulse signals and generate a time window signal to shield some interference signals.

[0010] Furthermore, the dual-pulse interval measurement module 5 includes a time window circuit module 16, a NOT gate 17, and two AND gates (18, 19). First, the time window signal is triggered in the time window circuit module 16. The time window signal enters the delay module 13 of the FPGA to adjust the time window width. After the signal comes out of the delay module, it will be divided into two paths. One path directly enters one of the AND gates, and the other path passes through the NOT gate 17 and then enters the other AND gate.

[0011] Furthermore, the time window circuit module 16 is composed of multiple NAND gates and a monostable multivibrator connected in series; the multiple NAND gates are used to delay the formation of the time window signal to ensure that the time window signal does not overlap with the first pulse signal, so as to ensure the integrity of the pulse signal when the signal is separated.

[0012] Furthermore, the signal measurement module includes a TDC4, which includes four channels: Start1, Stop1, Start2, and Stop2. Channels Start1 and Stop1 are used to measure the output of the dual-pulse generation circuit 3 and the echo signal from the transimpedance amplifier circuit 7, thereby obtaining the flight time of the echo signal. Channels Start2 and Stop2 are used to measure the dual-pulse signal of the dual-pulse interval measurement module 5, thereby obtaining the time interval between the rising edges of the two pulse signals.

[0013] On the other hand, the present invention also provides a method for lidar ranging and communication based on a dual-pulse interval, specifically including the following steps:

[0014] Step 1: Signal encoding and transmission;

[0015] In the signal transmission module, MCU1 encodes the binary communication content in the interval encoding module 10 of FPGA2, and determines the pulse interval according to its own radar IP. The pulse control module 14 outputs a pulse interval control signal according to the encoding result, thereby controlling the dual pulse generation circuit 3 to generate the corresponding dual pulse voltage signal. One path enters the LD drive circuit 6 to drive the laser diode 8 to emit a dual pulse laser signal; the other path enters the Start1 channel of TDC4 to enable the Stop1 channel to prepare for receiving the echo signal.

[0016] Step 2: Distance measurement;

[0017] In step one, part of the dual-pulse laser signal is reflected at the receiving radar to form an echo signal, which is received by the signal receiving module APD9. After being amplified by TIA7, it enters the Stop1 channel of TDC4. The measurement data is obtained by TDC4 and transmitted to TDC control module 15. The flight time Δt1 is handed over to the distance calculation module 11 to calculate the communication distance.

[0018] The communication distance is obtained by the following formula:

[0019]

[0020] In the formula, c is the speed of light in the atmosphere; Δt1 is the delay time of the echo signal;

[0021] The final communication distance will be transmitted to MCU1 to complete the ranging process;

[0022] Step 3: Signal processing and verification decoding;

[0023] The other part of the dual-pulse laser signal from step one is received by the signal receiving module of the receiving radar, and then transmitted back to APD9. It is then converted into a dual-pulse voltage signal by TIA7. The dual-pulse interval measurement module 5 separates signal S2 to obtain the separated pulse signals S6 and S7. The Start2 and Stop2 channels of TDC4 then perform rising edge interval T on the separated pulse signals. n Measurements are taken for IP identification and content decoding.

[0024] Furthermore, step three is completed by the interval decoding module 12, and specifically includes the following:

[0025] First, regarding T n The system performs a judgment to determine whether the signal is a radar signal and whether the rising edge interval of the double pulse is within the correct range, i.e., T. n Is it in (T) nmin ,T nmax ), that is, the IP of radar n = (T nmin ,T nmax When the measured pulse interval T n In (T) nmin ,T nmax If the signal is within 1 / 3 of the range (T), it indicates that the signal is an inter-radar communication signal and confirms the radar IP, allowing the next step of judgment; otherwise, the double-pulse signal is discarded and the system waits for the next reception. The next step is to identify the communication content. nmin ,T nmax The specific value T of the signal within the range n This represents the information transmitted by the radar.

[0026] Compared with the prior art, the advantages of the present invention are as follows:

[0027] 1. By combining pulse ranging with pulse communication, both distance measurement and communication can be achieved simultaneously, thus improving the level of system integration;

[0028] 2. Radar IP is added using FPGA, time window signals are generated using monostable multivibrators, and signal spacing is measured using TDC, resulting in lower device costs;

[0029] 3. At the receiving end, use a time window to block some irrelevant signals to improve the anti-interference capability of communication;

[0030] 4. Adopting a radar IP based on dual-pulse intervals prevents external interference and further improves the anti-interference capability of ranging and communication. Attached Figure Description

[0031] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the accompanying drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. In all the drawings, similar elements or parts are generally identified by similar reference numerals. In the drawings, the elements or parts are not necessarily drawn to scale.

[0032] Figure 1 This is a schematic diagram illustrating the working process of a lidar ranging and communication system based on a dual-pulse interval according to the present invention.

[0033] Figure 2 This is an overall block diagram of a lidar ranging and communication system based on a dual-pulse interval according to the present invention.

[0034] Figure 3 This is a schematic diagram of the internal modules of an FPGA.

[0035] Figure 4 This is a schematic diagram of the internal structure of the dual-pulse interval measurement module;

[0036] Figure 5 This is a diagram illustrating the internal signal processing of the dual-pulse interval measurement module.

[0037] Figure 6 The process and waveform of measuring the echo signal for TDC;

[0038] Figure 7 The process and waveform of measuring communication signals for TDC;

[0039] Figure 8 This is a waveform diagram of inter-radar communication based on double-pulse interval coding.

[0040] In the diagram: 1. Microcontroller (MCU), 2. Field Programmable Gate Array (FPGA), 3. Dual Pulse Generation Circuit, 4. Time-to-Digital Converter (TDC), 5. Dual Pulse Interval Measurement Module, 6. LD Driver Circuit, 7. Transimpedance Amplifier (TIA), 8. Laser Diode (LD), 9. Avalanche Photodiode (APD), 10. Interval Encoding Module, 11. Distance Calculation Module, 12. Interval Decoding Module, 13. Delay Module, 14. Pulse Control Module, 15. TDC Control Module, 16. Time Window Circuit Module, 17. NOT Gate, 18. AND Gate, 19. Detailed Implementation

[0041] The embodiments of the technical solution of the present invention will now be described in detail with reference to the accompanying drawings. The following examples are only used to more clearly illustrate the technical solution of the present invention. Therefore, they are merely examples and should not be used to limit the scope of protection of the present invention.

[0042] It should be noted that, unless otherwise stated, the technical or scientific terms used in this application should have the ordinary meaning understood by one of ordinary skill in the art to which this invention pertains.

[0043] Example 1

[0044] To achieve target identification and distance measurement in communication, such as Figure 1 As shown, this embodiment provides a system for lidar ranging and communication based on dual-pulse interval, including a signal processing module, a signal transmitting module, a signal receiving module, and a signal measurement module;

[0045] The signal processing module converts binary data into double-pulse intervals of a specific length, which are then passed to the signal transmitting module to be converted into corresponding double-pulse laser signals and transmitted. Part of the laser signal is reflected at the receiving radar to form an echo signal, which is received by the signal receiving part of the transmitting radar. After the signal is amplified, it enters its signal measurement module to obtain the signal flight time, which is then passed to the signal processing module to calculate the communication distance. Another part of the laser signal is received by the signal receiving part of the receiving radar, and after the signal is amplified, it enters the signal measurement module to obtain the time interval of the double-pulse signal.

[0046] like Figure 1 As shown, the signal processing module consists of two parts: a microcontroller (MCU) 1 and a field-programmable gate array (FPGA) 2. The MCU 1 transmits the communication content (audio, video, etc.) and local IP information to the FPGA 2, while the FPGA 2 is responsible for converting the signal into an interval length within a specified range and sending the pulse interval control signal to the dual pulse generation circuit of the signal transmission section.

[0047] like Figure 2As shown, the FPGA2 can be divided into 6 modules according to its functions: interval encoding module 12, pulse control module 14, distance calculation module 11, TDC control module 15, interval decoding module 12, and delay module 13. The interval encoding module 12 outputs the corresponding interval according to the communication content and its own radar IP information, and transmits it to the pulse control module 14 to become the pulse interval control signal required to control the dual pulse generation circuit 3; the TDC control module 15 is responsible for the management of TDC4, transmitting control signals to TDC4 and receiving measurement signals from TDC4. Depending on the channel of TDC4, it can be divided into dual pulse interval measurement signals and distance signals. The distance signal is transmitted to the distance calculation module 11, and the dual pulse interval measurement signal is transmitted to the interval decoding module 12; the distance calculation module 11 can calculate the communication distance after receiving the distance signal and then send it to MCU1; the interval decoding module 12 is responsible for deciphering the radar IP signal and communication signal contained in the dual pulse interval measurement signal and sending it to MCU1; the delay module 13 performs corresponding extension operations on the time window signal sent by the dual pulse interval measurement module 5 according to the instructions of MCU1, so as to adjust the width of the time window.

[0048] like Figure 1 As shown, the signal transmission module includes a dual-pulse generation circuit 3, an LD driving circuit 6, and an LD8. The dual-pulse generation circuit 3 receives the pulse interval control signal from the pulse control module 14 in the FPGA2, converts the interval information from digital to the corresponding current signal, and sends one signal to the TDC4 and the other signal to the LD driving circuit 6 to form the driving current required by the LD8. Finally, the LD8 emits a laser signal under the drive of the driving current.

[0049] like Figure 1 As shown, the signal receiving module includes an APD9, a transimpedance amplifier circuit 7, and a dual-pulse interval measurement module 5. The APD9 receives the laser signal in the air and converts it into an electrical signal. The signal is amplified by the transimpedance amplifier circuit 7, and one output signal goes directly to the Stop1 channel of the TDC4 to measure the flight time of the echo signal. The other output signal goes into the dual-pulse interval measurement module 5 to measure the dual-pulse interval. The dual-pulse interval measurement module 5 is responsible for separating the dual-pulse signal and generating a time window signal to shield some interference signals.

[0050] like Figure 3 As shown, the dual-pulse interval measurement module 5 includes a time window circuit module 16, a NOT gate 17, and two AND gates (18, 19), and the waveform... Figure 4As shown, signal S2 is divided into four paths. The top path, S2, enters the Stop1 channel and, together with the S1 signal from the dual-pulse generation circuit 3, measures the delay time (flight time) of the echo signal. Another path enters the time window circuit module 16 to trigger the time window signal S3. S3 then enters the delay module 13 in FPGA2, which delays the time window signal according to communication needs. It is worth noting that the wider the width of the monostable multivibrator output signal (time window width) (which can be adjusted by an external RC circuit), the more radars it covers, but the anti-interference capability decreases. The delayed time window signal S4 is divided into two paths. One path generates an inverted signal S5 through NOT gate 17, which, together with the dual-pulse signal S2, enters AND gate 18. This shields some interference signals outside the time window and also separates the pulse signal S6, which enters the Start2 channel. The last path, S2, together with the other path, the adjusted time window signal S4, enters AND gate 19 to separate the pulse signal S7, which enters the Stop2 channel and, together with S6 from the Start2 channel, completes the measurement of the dual-pulse interval.

[0051] The time window circuit module 12 is formed by connecting multiple NAND gates (CD4093BM96) and a monostable multivibrator (SM74HC123D) in series. The multiple NAND gates delay the formation of the time window signal, ensuring that the time window signal does not overlap with the first pulse signal, thus guaranteeing the integrity of the pulse signal during signal separation.

[0052] The signal measurement section has only one module: TDC4, such as... Figure 1 As shown. Commonly available TDC models include TDC-GP22, TDC7200PW, and TDC-GPX2. This patent uses the TDC-GPX2 manufactured by AMS, with a single-channel accuracy of up to 20ps. This patent utilizes four channels of this chip: Start1, Stop1, Start2, and Stop2. Start1 and Stop1 are used to measure the output of the dual-pulse generation circuit 3 and the echo signal from the transimpedance amplifier circuit 7, thus obtaining the flight time of the echo signal; Start2 and Stop2 are used to measure the dual-pulse signal of the dual-pulse interval measurement module 5, thus obtaining the time interval between the rising edges of the two pulse signals.

[0053] Example 2

[0054] This embodiment provides a method for lidar ranging and communication based on dual-pulse intervals, specifically including the following steps:

[0055] Step 1: Signal encoding and transmission;

[0056] The MCU1 in the signal transmission section encodes the binary communication content (including audio, video, etc.) in FPGA2, and determines the square wave pulse interval based on its own radar IP. Considering circuit parameters and device performance, different radixes can be selected for the pulse interval. The higher the radix, the higher the accuracy requirement for the transmitted signal of the circuit, and the higher the accuracy requirement for the TDC4 measurement at the receiving end.

[0057] Radar communication waveforms such as Figure 8 As shown, each radar x occupies a separate communication area (T). xmin ,T xmax The position (interval length) of pulse P2 is determined based on the communication content and radar IP.

[0058] Afterwards, the pulse control module 14 will output a pulse interval control signal according to the encoding result, thereby controlling the dual pulse generation circuit 3 to generate the corresponding dual pulse voltage signal. One path enters the LD drive circuit 6 to drive the laser diode 8 to emit a dual pulse laser signal; the other path enters the Start1 channel of TDC4 to enable the Stop1 channel to prepare to receive the echo signal.

[0059] Step 2: Distance measurement;

[0060] In step one, part of the dual-pulse laser signal is reflected at the receiving radar to form an echo signal, which is received by the transmitting radar APD9. After being amplified by TIA7, it enters the Stop1 channel of TDC4. The measurement data is obtained by TDC4 and transmitted to TDC control module 15. The flight time Δt1 is handed over to the distance calculation module 11 to calculate the communication distance.

[0061] The communication distance is obtained by the following formula:

[0062]

[0063] In the formula, c is the speed of light in the atmosphere; Δt1 is the delay time of the echo signal;

[0064] The final communication distance will be transmitted to MCU1 to complete the ranging process.

[0065] The measurement in this invention uses four channels of the TDC, with two channels used to measure one signal. Figure 5 This demonstrates the process of measuring the echo signal and identifying the self-emitted signal using a TDC. Refclk is the reference clock input signal. The Start1 channel receives the double-pulse current signal from the double-pulse generation circuit 24, and the Stop1 channel receives the echo signal (also in the form of a double-pulse signal) from TIA21. From this, the delay time (time of flight) Δt1 of the echo signal can be measured. Simultaneously, the Start2 and Stop2 channels measure the interval T of the double-pulse signal.n It determines whether the signal is its own and confirms the validity of the ranging.

[0066] Step 3: Signal processing and verification decoding;

[0067] The other part of the dual-pulse laser signal from step one is received by the APD9 of the receiving radar, converted into a dual-pulse voltage signal by TIA7, and then processed by the dual-pulse interval measurement module 5 to separate the signal S2, obtaining the separated pulse signals S6 and S7. The Start2 and Stop2 channels of TDC4 then measure the rising edge interval of the separated pulse signals for IP identification and content decoding, such as... Figure 6 As shown, the measurement process is similar to the steps above, but the receiving radar does not need to consider ranging. Although the Stop1 channel can still receive signals, the Start1 channel is not activated.

[0068] The signal processing procedures before entering the Start2 and Stop2 channels are as follows: Figure 3 As shown, the waveform is as follows Figure 4 As shown. Before the TDC4 measurement, the dual-pulse interval measurement module processes the dual-pulse signal. First, the dual-pulse signal enters the time window circuit module 16, where it will form a signal delay Δt3 under the action of multiple NAND gates and delay modules 13. To ensure the integrity of the pulse signal, Δt3 must meet the following requirements:

[0069] Δt3>τ (2)

[0070] Δt4 is adjusted by the delay module 13 in FPGA2. The combination of Δt3 and Δt4 can control the position and width of the time window signal to cope with different radar signals.

[0071] First, regarding T n To determine if it is a radar signal, observe whether the rising edge interval of the double pulse is within the correct range, i.e., T. n Is it in (T) nmin ,T nmax ), that is, the IP of radar n = (T nmin ,T nmax When the measured pulse interval T n In (T) nmin ,T nmax If the signal is received within the specified range, it indicates that the signal is an inter-radar communication signal and the radar IP is confirmed, allowing the next step of judgment. Otherwise, the double-pulse signal is discarded, and the system waits for the next reception. The next step is to identify the communication content. nmin ,T nmax The specific value T of the signal within the range n This represents the information transmitted by the radar.

[0072] The preferred embodiments of the present invention have been described in detail above with reference to the accompanying drawings. However, the present invention is not limited to the specific details of the above embodiments. Within the scope of the technical concept of the present invention, various simple modifications can be made to the technical solution of the present invention, and these simple modifications all fall within the protection scope of the present invention.

[0073] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. In order to avoid unnecessary repetition, the present invention will not describe the various possible combinations separately.

[0074] Furthermore, various different embodiments of the present invention can be combined in any way, as long as they do not violate the spirit of the present invention, they should also be regarded as the content disclosed by the present invention.

Claims

1. A system for lidar ranging and communication based on dual-pulse intervals, characterized in that, It includes a signal processing module, a signal transmitting module, a signal receiving module, and a signal measurement module. The signal processing module converts binary data into double-pulse intervals of a specific length and sends them to the signal transmitting module, which converts them into corresponding double-pulse laser signals. Part of the laser signal is reflected at the communication target and received by the transmitting radar for ranging purposes, while the other part is directly received by the receiving radar for communication purposes. The signal measurement module measures the double-pulse signals transmitted from the signal receiving module, calculates the flight time of the double-pulse signals, and then sends the data back to the signal processing module. The signal processing module includes a microcontroller (1) and a field-programmable gate array (FPGA) (2). The microcontroller (1) is used to transmit communication content and local IP information to the FPGA (2). The FPGA (2) is used to convert the signal into an interval length within a specified range and send the pulse interval control signal to the dual pulse generation circuit of the signal transmission module. The FPGA (2) includes an interval encoding module (10), a pulse control module (14), a distance calculation module (11), a TDC control module (15), an interval decoding module (12), and a delay module (13). The interval encoding module (12) is used to output the corresponding interval according to the communication content and its own radar IP information, and transmit it to the pulse control module (14) to convert it into the pulse interval control signal required by the dual pulse generation circuit (3) of the control signal transmission module. The TDC control module (15) is used to control the signal measurement module, transmit control signals to the signal measurement module, and receive measurement signals from the signal measurement module. The measurement signals are transmitted according to the signal measurement module. The signals can be divided into dual-pulse interval measurement signals and distance signals. The distance signal is sent to the distance calculation module (11), and the dual-pulse interval measurement signal is sent to the interval decoding module (10). The distance calculation module (11) calculates the communication distance after receiving the distance signal and then sends it to the microcontroller (1). The interval decoding module (10) is used to interpret the radar IP signal and communication signal contained in the dual-pulse interval measurement signal and send them to the microcontroller (1). The delay module (13) is used to perform corresponding extension operations on the time window signal sent by the dual-pulse interval measurement module (5) according to the instructions of the microcontroller (1) in order to adjust the width of the time window. The signal receiving module includes an avalanche photodiode (APD) (9), a transimpedance amplifier circuit (7), and a double pulse interval measurement module (5). The APD (9) receives laser signals in the air and converts them into electrical signals. The signals are amplified by the transimpedance amplifier circuit (7), and the output signals are sent to the Stop (1) channel of the TDC (4) to measure the flight time of the echo signals. The other signal is sent to the double pulse interval measurement module (5) to measure the double pulse interval. The double pulse interval measurement module (5) is used to separate the double pulse signals and generate a time window signal to shield some interference signals. The dual-pulse interval measurement module (5) includes a time window circuit module (16), a NOT gate (17) and two AND gates. First, the time window signal is triggered in the time window circuit module (16). The time window signal enters the delay module (13) of the FPGA to adjust the time window width. After the signal comes out of the delay module, it will be divided into two paths. One path directly enters one of the AND gates, and the other path passes through the NOT gate (17) and then enters the other AND gate. The time window circuit module (16) consists of multiple NAND gates and a monostable multivibrator connected in series; the multiple NAND gates are used to delay the formation of the time window signal to ensure that the time window signal does not overlap with the first pulse signal, so as to ensure the integrity of the pulse signal when the signal is separated. The signal measurement module includes: TDC (4), which includes four channels, namely Start1, Stop1, Start2, and Stop2; among them, channels Start1 and Stop1 are used to measure the output of the dual pulse generation circuit (3) and the echo signal transmitted from the transimpedance amplifier circuit (7), and the flight time of the echo signal can be obtained; channels Start2 and Stop2 are used to measure the dual pulse signal of the dual pulse interval measurement module (5), and the time interval between the rising edges of the two pulse signals can be obtained.

2. The system for lidar ranging and communication based on a dual-pulse interval as described in claim 1, characterized in that, The signal transmitting module includes a dual pulse generating circuit (3), an LD driving circuit (6), and an LD (8). The dual pulse generating circuit (3) is used to receive the pulse interval control signal from the pulse control module (16) in the FPGA (2), convert the pulse interval control signal from digital to the corresponding current signal, send one signal to the TDC (4), and send the other signal to the LD driving circuit (6) to form the driving current required by the LD (8). Finally, the LD (8) emits a laser signal under the drive of the driving current.

3. A control method for a lidar ranging and communication system based on a dual-pulse interval as described in claim 1, specifically comprising the following steps: Step 1: Signal encoding and transmission; The MCU (1) in the signal transmission module encodes the binary communication content in the interval encoding module (10) of the FPGA (2), and determines the pulse interval according to its own radar IP; the pulse control module (14) outputs the pulse interval control signal according to the encoding result, thereby controlling the double pulse generation circuit (3) to generate the corresponding double pulse voltage signal, one of which enters the LD driving circuit (6) to drive the laser diode (8) to emit the double pulse laser signal; the other enters the Start1 channel of the TDC (4) to enable the Stop1 channel to prepare to receive the echo signal; Step 2: Distance measurement; Part of the dual-pulse laser signal from step one will be reflected at the receiving radar to form an echo signal, which is received by the APD (9) of the signal receiving module. After being amplified by the TIA (7), it enters the Stop (1) channel of the TDC (4). The TDC (4) obtains the measurement data, transmits it to the TDC control module (15), and records the flight time. The communication distance is calculated by the distance calculation module (11); The communication distance is obtained by the following formula: (1) In the formula, c is the speed of light in the atmosphere; This is the delay time of the echo signal; The final communication distance will be transmitted to the MCU (1) to realize the complete ranging process; Step 3: Signal processing and verification decoding; The other part of the double-pulse laser signal from step one is received by the signal receiving module of the receiving radar and then sent back to the APD (9). It is then converted into a double-pulse voltage signal by the TIA (7). The signal S2 is separated by the double-pulse interval measurement module (5) to obtain the separated pulse signals S6 and S7. The Start2 channel and Stop2 channel of the TDC (4) then perform rising edge interval processing on the separated pulse signals. Measurements are taken for IP identification and content decoding.

4. The control method for a lidar ranging and communication system based on a dual-pulse interval as described in claim 3, characterized in that, Step 3 is completed by the interval decoding module (12), and specifically includes the following: First of all, The system performs a judgment to determine whether it is a radar signal and whether the rising edge interval of the double pulse is within the correct range. Is it in That is, radar n When the measured pulse interval exist If the signal is confirmed to be an inter-radar communication signal and the radar IP is verified, the next step of judgment can proceed; otherwise, the double-pulse signal is discarded and the system waits for the next reception. The next step is to identify the communication content. Specific signal values ​​within the range This represents the information transmitted by the radar.

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