High interference immunity dual pulse lidar ranging and communication system and method

Abstract

The application discloses a high anti-interference double-pulse laser radar ranging and communication system and method, and belongs to the technical field of instruments and meters. The system and method correspond different signaling radars or signaling signals to different pulse intervals, shield irrelevant signals by using the transient duration of a fixed monostable trigger, referred to as a time window, at a receiving end, use two monostable triggers, one of which has adjustable transient time and the other of which has fixed transient time, adjust the position of the time window by reasonably setting the transient time of the adjustable monostable trigger, reasonably set the window width by the transient duration of the fixed monostable trigger, ensure that useful information is separated, and shield the interference signals outside the window by the combination of the two, thereby greatly improving the anti-interference capability. The system and method realize communication, identify and measure the distance of a signaling object, have strong anti-interference capability, and have certain practical value in communication occasions among multiple radars.

Description

Technical Field

[0001] This invention belongs to the field of instrumentation technology, specifically relating to a highly anti-interference dual-pulse lidar ranging and communication system and method. Background Technology

[0002] Due to its advantages such as good stability and high brightness, lasers are widely used in ranging systems. Simultaneously, 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 automotive accessory, with multiple lidar units existing in the same application scenario. In current lidar systems, pulsed laser ranging has many advantages, including simple ranging structure, long range, high repetition frequency, and fast measurement speed, thus gaining widespread application. In multi-pulse lidar applications, mutual interference between lidars is a critical problem that urgently needs to be solved. Therefore, improving the anti-interference performance of dual-pulse interval lidar is one of the key future development directions. Summary of the Invention

[0003] To address the weaknesses in anti-interference capabilities of existing technologies, this invention proposes a highly anti-interference dual-pulse lidar ranging and communication system and method. This system and method employs different pulse intervals corresponding to different transmitting radars or signals. At the receiving end, a fixed transient duration of a monostable multivibrator, termed a time window, is used to shield irrelevant signals. Two monostable multivibrators are employed: one with an adjustable transient time and the other with a fixed transient time. The position of the time window is adjusted by rationally setting the transient time of the adjustable monostable multivibrator, and the window width is rationally set by fixing the transient duration of the monostable multivibrator, ensuring the separation of useful information. The combination of these two methods effectively shields interference signals outside the window, significantly improving anti-interference capabilities. This system and method simultaneously achieve communication, identify the transmitting target, and measure distance, exhibiting strong anti-interference capabilities and demonstrating practical value in various inter-radar communication scenarios.

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

[0005] A highly interference-resistant dual-pulse lidar ranging and communication system includes a source transmitter 1 and a destination receiver 9. The source transmitter 1 includes a microcontroller (MCU) 2, a field-programmable gate array (FPGA) 3, a dual-pulse generation circuit 4, a laser diode (LD) pulse emission circuit 5, an avalanche diode (APD) pulse receiving circuit 6, a dual-pulse interference-resistant processing module 7, and a time-to-digital converter (TDC) chip 8. The microcontroller 2 sends lidar IP information to the FPGA 3. The FPGA 3 modulates the signal using dual pulses and then sends the modulated signal containing the baseband signal to the dual-pulse generation circuit 4. The dual-pulse generation circuit 4 generates the modulated dual-pulse signal. A portion of the signal is transmitted to the laser diode (LD) pulse transmitting circuit 5 to transmit the modulated double pulse signal into the channel. The signal in the channel is reflected and refracted and then received by the avalanche diode (APD) pulse receiving circuit 6. The other portion is received by the receiver 9. The signal received by the avalanche diode (APD) pulse receiving circuit 6 is processed by the double pulse anti-interference processing module 7 and then sent to the TDC8. After time-to-digital conversion by the TDC8, the measured distance information and double pulse interval information can be obtained. The TDC8 then sends the measured information to the FPGA3 and MCU2, which can simultaneously realize ranging and communication and improve the anti-interference capability of the system.

[0006] Furthermore, the dual-pulse anti-interference processing module 7 includes a delay module 10, a monostable multivibrator 11 with adjustable transient time ΔT1, NOT gate I 12, a monostable multivibrator 13 with fixed transient time ΔT2, NOT gate II 14, AND gate I 15, and AND gate II 16. After the signal received by the avalanche diode (APD) pulse receiving circuit 6 is sent to this module, a portion is directly sent to AND gate I 15 and AND gate II 16 without any processing, serving as the first input signal for AND gate I 15 and AND gate II 16; the other portion is sent to the delay module 10, where the signal is briefly delayed, and then further sent to the monostable multivibrator 11 with adjustable transient time ΔT1. This trigger is a rising edge trigger, and after time ΔT1... The signal output of the adjustable monostable multivibrator 11 is further divided into two parts. One part is inverted by NOT gate I 12 and sent to AND gate II 16 as the second input signal of AND gate II 16. The other part is sent to the monostable multivibrator 13 with a fixed transient time ΔT2. This multivibrator is triggered by a falling edge. The signal output of the monostable multivibrator 13 with a fixed transient time ΔT2 is directly output to AND gate I 15 as the second input signal of AND gate I 15. The other part is inverted by NOT gate II 14 and output to AND gate II 16 as the third input signal of AND gate II 16. The output signal of AND gate II 16 is sent to the Start2 channel of TDC8, and the output of AND gate I 15 is sent to the Stop2 channel of TDC8.

[0007] Furthermore, the TDC8 includes four channels, namely Start1, Stop1, Start2, and Stop2; wherein, channels Start1 and Stop1 are used to measure the flight time of the double-pulse interval signal; channels Start2 and Stop2 are used to measure the double-pulse interval signal, and the time interval between the rising edges of the two pulse signals can be obtained.

[0008] On the other hand, the present invention also provides a highly anti-interference dual-pulse lidar ranging and communication method, which is implemented based on the above system and specifically includes the following steps:

[0009] Step 1: Generation and transmission of dual-pulse interval laser pulses;

[0010] The microcontroller 2 in the source transmitter 1 sends the radar IP information to the FPGA 3. The FPGA 3 uses the IP information as a baseband signal to generate a double pulse interval control signal. The double pulse interval time is Tn, which carries the radar IP information. After the FPGA 3 processes the signal, it sends the control signal to the double pulse generation circuit 4. The double pulse generation circuit 4 generates a modulated double pulse signal. The double pulse interval information of this signal is the baseband information to be transmitted. Part of this signal is passed to the laser diode (LD) pulse transmitting circuit 5 to transmit the modulated double pulse signal into the channel, and the other part is passed to the Start1 channel of the time-to-digital converter chip TDC8 as the TDC's start signal.

[0011] Step 2: Dual-pulse interval laser pulse reception and demodulation;

[0012] The avalanche diode (APD) pulse receiving circuit 6 receives the echo signal reflected back from the target being measured. Part of it is sent to the Stop1 channel of the time-to-digital converter chip TDC8 as the stop signal for the first channel of TDC; the other part is sent to the dual-pulse anti-interference processing module 7 to demodulate the dual-pulse interval signal, and the two demodulated pulses are transmitted to the Start2 and Stop2 channels of TDC8 respectively, so that the time difference Tn of the second channel of TDC can be measured.

[0013] Step 3: Measure the distance and decode the baseband information;

[0014] TDC8 sends the distance signal Δt and the time difference Tn of the second channel back to FPGA3. FPGA3 then transmits the data back to MCU2, which processes the data and further calculates the measured distance. On the other hand, FPGA3 demodulates the time difference Tn of the second channel according to the modulation method to obtain the baseband signal encoded by the double pulse interval, i.e., the radar's IP address; the system simultaneously realizes ranging and communication.

[0015] Furthermore, the difference Δt between the counting times of Start1 and Stop1 in channel 1 of TDC8 is the flight time of the dual-pulse laser signal emitted by the source transmitter in the channel, according to the formula:

[0016]

[0017] Where c is the speed of light, and d is half the distance the dual-pulse laser signal travels in the channel, which is the distance between the target measured by the dual-pulse radar and the lidar, thus realizing the lidar ranging function.

[0018] Furthermore, the dual-pulse anti-interference processing module 7 sends a portion of the received dual-pulse interval signal directly to AND gate I 15 and AND gate II 16 without any processing, as the signal to be processed; the other portion is sent to the delay module 10, and further to the monostable multivibrator 11 with adjustable transient time ΔT1. A portion of the monostable multivibrator 11 with adjustable transient time ΔT1 is inverted by NOT gate I 12 and sent to AND gate II 16 as the second input signal of AND gate II 16. The other portion is sent to the monostable multivibrator 13 with fixed transient time ΔT2. A portion of this trigger is directly output to AND gate I 15 as the second input signal of AND gate I 15, and the other portion is inverted by NOT gate II 14 and output to AND gate II 16 as the third input signal of AND gate II 16.

[0019] Furthermore, the high-level duration ΔT1 of the output waveform of the monostable multivibrator 11 with adjustable transient time ΔT1 is adjustable. This signal can be used as the trigger signal for the monostable multivibrator 13 with fixed transient time ΔT2. When the output level of the monostable multivibrator 11 with adjustable transient time ΔT1 jumps from high to low, the monostable multivibrator 13 with fixed transient time ΔT2 is triggered. The high-level duration ΔT2 of this trigger is fixed, and this high-level duration is defined as the time window. This signal is ANDed with the double-pulse interval signal through AND gate I 15 to separate the second pulse of the double-pulse interval signal that falls within the time window. Any interference signals outside the time window will be shielded. At the same time, in order to prevent the second pulse from interfering with the output of AND gate II 16, the monostable multivibrator with fixed transient time ΔT2 can be... The output of transmitter 13 is inverted to shield the pulse, ensuring that AND gate II 16 only separates the first pulse of the double-pulse interval signal. The first pulse separated by AND gate II 16 is sent to the Start2 channel of TDC8, and the second pulse separated by AND gate I 15 is sent to the Stop2 channel of TDC8. The Stop2 channel is measured by TDC8, and the time difference Tn of the second channel can be measured. The double-pulse anti-interference processing module 7 adjusts the position of the time window by reasonably setting the transient time ΔT1 of the adjustable monostable trigger, and by reasonably setting the window width ΔT2, ensures that only the second pulse of the double-pulse interval signal is separated as the input signal of the Stop2 channel, and shields all interference signals outside the window. The combination of the two can greatly improve the anti-interference capability.

[0020] Furthermore, the delay time of the delay module 10 is greater than the pulse width of the double-pulse interval signal, ensuring that the output of NOT gate I 12 and the double-pulse interval signal can be separated into the first pulse of the double-pulse interval signal after being ANDed by AND gate II 16.

[0021] Compared with the prior art, the advantages of the present invention are as follows:

[0022] 1. The system and method of the present invention have a large capacity of encoded signal information. One system can encode the IP information of multiple lidars, realizing the communication and identification of multiple lidars.

[0023] 2. The components used are relatively inexpensive, resulting in a low overall implementation cost;

[0024] 3. The dual-pulse anti-interference processing module processes the dual-pulse interval signal, further improving the anti-interference capability;

[0025] 4. This method is universal and applicable to various types of pulsed laser emitting and receiving circuits. It is highly practical and portable. Attached Figure Description

[0026] 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.

[0027] Figure 1 This is a schematic diagram of the high anti-interference dual-pulse lidar ranging and communication system of the present invention;

[0028] Figure 2 This is a structural diagram of the dual-pulse anti-interference processing module;

[0029] Figure 3 Waveform diagram of key nodes in the dual-pulse anti-interference processing module;

[0030] Figure 4 This diagram shows the specific connection relationship between the dual-pulse anti-interference processing module and the TDC.

[0031] Figure 5 The waveforms of each channel and time window of TDC are shown.

[0032] In the diagram: 1. Source transmitter; 2. Microcontroller (MCU); 3. Field-Programmable Gate Array (FPGA); 4. Dual pulse generation circuit; 5. Laser diode (LD) pulse emission circuit; 6. Avalanche diode (APD) pulse receiving circuit; 7. Dual pulse anti-interference processing module; 8. Time-to-digital converter (TDC) chip; 9. Destination receiver; 10. Delay module; 11. Monostable multivibrator with adjustable transient time ΔT1; 12. NOT gate; 13. Monostable multivibrator with fixed transient time ΔT2; 14. NOT gate; 15. AND gate I; 16. AND gate II; Δt, the flight time of the dual-pulse laser signal emitted by the source transmitter in the channel; ΔT1, the adjustable single-flipper transient time; Delay, the delay of the delay module; Delay+ΔT1, the delay module plus the adjustable single-flipper transient time; ΔT2, the fixed single-flipper transient time; Tn, the pulse interval time. Detailed Implementation

[0033] To clearly and completely describe the technical solution and its specific working process of the present invention, the specific embodiments of the present invention are as follows, in conjunction with the accompanying drawings:

[0034] Example 1

[0035] like Figure 1As shown, the high anti-interference dual-pulse lidar ranging and communication system provided in this embodiment includes a source transmitter 1 and a destination receiver 9. The source transmitter 1 includes a microcontroller MCU 2, a field-programmable gate array (FPGA) 3, a dual-pulse generation circuit 4, a laser diode (LD) pulse transmitting circuit 5, an avalanche diode (APD) pulse receiving circuit 6, a dual-pulse anti-interference processing module 7, and a time-to-digital converter (TDC) chip 8. The microcontroller 2 sends the lidar IP information to the FPGA 3, and the FPGA 3, after dual-pulse modulation, sends the modulated signal containing the baseband signal to the dual-pulse generation circuit 4. The dual-pulse generation circuit 4 generates the modulated dual pulses. The signal is transmitted in two stages. Part of the signal is transmitted to the laser diode (LD) pulse transmitting circuit 5 to transmit the modulated double pulse signal into the channel. The signal in the channel is reflected and refracted and then received by the avalanche diode (APD) pulse receiving circuit 6. The other part is received by the sink receiver 9. The signal received by the avalanche diode (APD) pulse receiving circuit 6 is processed by the double pulse anti-interference processing module 7 and then sent to the TDC8. After the TDC8 performs time-to-digital conversion, the measured distance information and double pulse interval information can be obtained. The TDC8 then sends the measured information to the FPGA3 and MCU2, which can simultaneously realize ranging and communication and improve the anti-interference capability of the system.

[0036] The TDC8 includes four channels: Start1, Stop1, Start2, and Stop2. Channels Start1 and Stop1 are used to measure the flight time of the double-pulse interval signal, while channels Start2 and Stop2 are used to measure the double-pulse interval signal, thus obtaining the time interval between the rising edges of the two pulse signals.

[0037] The dual-pulse anti-interference processing module 7 includes a delay module 10, a monostable multivibrator 11 with adjustable transient time ΔT1, an NOT gate 12, a monostable multivibrator 13 with fixed transient time ΔT2, an NOT gate 14, an AND gate I 15, and an AND gate II 16. The signal received by the avalanche diode (APD) pulse receiving circuit 6 is sent to this module. Part of the signal is sent directly to AND gate II 16 without any processing, serving as its first input signal. The other part is sent to the delay module 10, where the signal is briefly delayed before being further sent to the monostable multivibrator 11 with adjustable transient time ΔT1. This trigger is a rising edge trigger. The signal output from the monostable multivibrator 11 with adjustable time ΔT1 is further divided into two parts: one part is inverted by the NOT gate 12 and sent to AND gate II 16 as its second input signal; the other part is sent to the monostable multivibrator 13 with fixed transient time ΔT2, which is a falling edge trigger. The monostable multivibrator 13, with a fixed transient time ΔT2, outputs a portion of its signal directly to AND gate I 15 as its first input signal, and the other portion is inverted by NOT gate 14 and output to AND gate I 15 as its second input signal. The output signal of AND gate II 16 is sent to the Start2 channel of TDC8, and the output of AND gate I 15 is sent to the Stop2 channel of TDC8.

[0038] The key node waveforms of the dual-pulse anti-interference processing module 7 mentioned above are as follows: Figure 3 As shown, after the waveform enters this module, part of it is directly sent to AND gates I 15 and II 16, while the other part, after a short delay, is sent to a monostable multivibrator with an adjustable transient time. This multivibrator is rising-edge triggered, which can widen the pulse to a width of ΔT1, and this width is adjustable. The signal is split into two paths: one path is inverted and sent to AND gate II 16, and the other path passes through a monostable multivibrator 13 with a fixed transient time. This multivibrator is falling-edge triggered, generating a window function with a fixed width ΔT2. One path of this window function serves as the gating signal for AND gate I 15, and the other path serves as the shielding signal for AND gate II 16. The window width is set reasonably, which can effectively shield interference signals outside the window, greatly improving the anti-interference capability. The specific connection relationship between this module and TDC is shown in the diagram below. Figure 4 As shown, the two demodulated pulses are transmitted to the Start2 and Stop2 channels of TDC8 respectively, and the time difference of the second channel of TDC can be measured. The waveforms and time window waveforms of each channel of TDC are shown in Figure 5. The Δt measured by Start1 and Stop1 is the flight time of the double-pulse laser signal emitted by the source transmitter in the channel. The measured distance can be calculated by formula (1). The Tn measured by Start2 and Stop2 is the baseband signal encoded by the double pulse interval.

[0039] The dual-pulse anti-interference processing module 7 internally uses a delay circuit, two NOT gates, and an AND gate. In practice, it can be implemented using NAND gate chips or built using the internal logic of an FPGA chip. The transient-time adjustable monostable multivibrator and the transient-time fixed monostable multivibrator can be implemented using dedicated integrated circuit chips and peripheral devices. TDC time-to-digital converter chips come in several types; this embodiment uses the AMS-manufactured TDC-GPX2, which has a single-channel accuracy of up to 20ps. Two channels, 1 and 2, are used. The specific connection diagram between the dual-pulse anti-interference module and the two TDC channels is shown below. Figure 4 As shown.

[0040] Example 2

[0041] This embodiment provides a highly interference-resistant dual-pulse lidar ranging and communication method, which specifically includes the following steps:

[0042] Step 1: Generation and transmission of dual-pulse interval laser pulses;

[0043] First, MCU2 sends the information to be transmitted (such as radar IP) to FPGA3. FPGA3 uses this information as a baseband signal to generate a double-pulse interval control signal. The double-pulse interval time Tn is the information carried, i.e., the radar IP signal. For example, the encoding interval time for radar 1 is T1, and for radar 2 it is T2. The encoding interval Tn is (Tmin, Tmax). Within this interval, n radar IPs can be encoded, i.e., T1, T2, ..., Tn. The width of this interval can be set by FPGA3. By setting the interval width, the number of radar codes can be increased or decreased. When the interval width is wider, the number of radars n that can be encoded increases. In this way, the number of radars that the system can communicate with is increased. The encoded double-pulse interval signal is as follows: Figure 5 As shown in Start1. After encoding, this control information is passed to the dual-pulse generation circuit 4 to generate an electrical signal. Part of this signal is sent to TDC8, and the other part is sent to the laser diode (LD) pulse emission circuit to convert the electrical signal into a laser signal and emit it into the channel.

[0044] Step 2: Dual-pulse interval laser pulse reception and demodulation;

[0045] The avalanche diode (APD) pulse receiving circuit 6 receives the echo signal reflected back from the target. It converts this signal from optical to electrical, and then sends a portion of this electrical signal directly to the Stop1 channel of the time-to-digital converter chip TDC8 as the stop signal for channel 1 of the TDC. The difference Δt between the counting times of the Start1 and Stop1 channels is the flight time of the dual-pulse laser signal emitted by the source transmitter in the channel, according to the formula:

[0046]

[0047] Where c is the speed of light, Δt is the flight time of the dual-pulse laser in the channel, and d is half the distance the dual-pulse laser signal travels in the channel, which is the distance between the target measured by the dual-pulse radar and the lidar. Δt contains the distance information. Another part is sent to the dual-pulse anti-interference processing module 7. This module has the function of demodulating the dual-pulse interval signal, which can separate the two pulses of the dual-pulse signal and send them to the Start2 and Stop2 channels of TDC8 respectively. The waveform diagram of the key nodes of this module is shown below. Figure 3 As shown. After the first pulse of the dual-pulse signal arrives, it is briefly delayed and then sent to a monostable multivibrator with an adjustable transient time, denoted as ΔT1. This adjustable transient time is then sent to the trigger signal of a monostable multivibrator with a fixed transient time ΔT2. Part of the signal output from the fixed-transient-time ΔT2 monostable multivibrator is directly used as the gating signal for the Stop2 port, and the other part is used as the shielding signal for Start2. Passing this signal through an AND gate separates it into two pulses, which are then sent to the Start2 and Stop2 ports respectively. The delay module's delay is Delay, and the adjustable-time monostable multivibrator's adjustable delay is ΔT1. Delay + ΔT1 is the delay module plus the adjustable single-flipper transient time; this time is the actual position of the time window. By changing this time, the position of the time window can be changed. This ensures that the time window function generated by the fixed-ΔT2 monostable multivibrator can sample the second pulse of the dual-pulse interval signal, and that the signal after the time window function is applied can shield the first pulse of the dual-pulse interval signal. Meanwhile, the time window width ΔT2 is fixed, which is ΔT2 = Tmax - Tmin. Outside the effective time window, all possible interference signals on the Stop2 port are filtered out, greatly improving the system's anti-interference capability. The specific connection diagram between this module and TDC is shown below. Figure 4 As shown, the two pulses demodulated by this module are transmitted to the Start2 and Stop2 channels of TDC8, respectively. The generated and received double-pulse interval electrical signals are sent to the Start1 and Stop1 channels, respectively. The waveforms on the four channels and the waveforms within the time window are shown below. Figure 5 As shown, Δt is the flight time of the dual-pulse laser signal emitted by the source transmitter in the channel; ΔT1 is the adjustable single-trigger transient time; Delay is the delay of the delay module; Delay+ΔT1 is the delay module plus the adjustable single-trigger transient time; ΔT2 is the fixed single-trigger transient time; and Tn is the pulse interval time. Thus, the time parameter Δt carrying distance information and the time parameter Tn carrying IP information can be obtained simultaneously.

[0048] Step 3: Measure the distance and decode the baseband information;

[0049] The TDC module obtains the time parameter Δt carrying distance information and the time parameter Tn carrying IP information, and then sends the information to FPGA3 and MCU2. MCU2 calculates the distance measured by the system according to formula (1.1). Based on Tn, if Tn is within the encoding range (Tmin, Tmax), it is considered a valid signal; otherwise, it is considered an interference signal, further enhancing the anti-interference capability. After obtaining Tn, the information it contains is decoded. For example, if radar 1 transmits information T1, and the received information is also T1, it proves that the received echo is the modulated wave transmitted by the local unit, and the measured distance is the distance between the local unit and the target. If the received information is T2, the received waveform is the information transmitted by another radar. Thus, the system realizes ranging and communication functions, and the system has a high anti-interference capability.

[0050] 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.

[0051] 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.

[0052] 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 highly anti-interference dual-pulse lidar ranging and communication system, characterized in that, The system includes a source transmitter (1) and a destination receiver (9); the source transmitter (1) includes a microcontroller (MCU) (2), a field-programmable gate array (FPGA) (3), a dual-pulse generation circuit (4), a laser diode pulse emission circuit (5), an avalanche diode pulse receiving circuit (6), a dual-pulse anti-interference processing module (7), and a time-to-digital converter (TDC) chip (8); the MCU (2) sends radar IP information to the FPGA (3), and the FPGA (3) sends a modulated signal containing baseband signals to the dual-pulse generation circuit (4) after dual-pulse modulation; the dual-pulse generation circuit (4) generates a modulated dual-pulse signal, which... One part is transmitted to the laser diode pulse transmitting circuit (5) to transmit the modulated double pulse signal into the channel. The signal in the channel is received by the avalanche diode pulse receiving circuit (6) after reflection and refraction. The other part is received by the sink receiver (9). The signal received by the avalanche diode pulse receiving circuit (6) is processed by the double pulse anti-interference processing module (7) and then sent to the TDC (8). After the TDC (8) performs time-to-digital conversion, the measured distance information and double pulse interval information can be obtained. The TDC (8) then sends the measured information to the FPGA (3) and MCU (2), so that distance measurement and communication can be realized at the same time, and the anti-interference capability of the system can be improved. The dual-pulse anti-interference processing module (7) includes a delay module (10) and a transient time. Adjustable monostable multivibrator (11), NOT gate I (12), transient time Fixed monostable multivibrator (13), NOT gate II (14), AND gate I (15), and AND gate II (16); after the signal received by the avalanche diode pulse receiving circuit (6) is sent to this module, part of it is sent directly to AND gate I (15) and AND gate II (16) without any processing, as the first input signal of AND gate I (15) and AND gate II (16); the other part is sent to the delay module (10) to delay the signal briefly, and then further send the signal to the transient time. An adjustable monostable multivibrator (11) is triggered on the rising edge and after a certain time. The signal output of the adjustable monostable multivibrator (11) is further divided into two parts. One part is inverted by NOT gate I (12) and sent to AND gate II (16) as the second input signal of AND gate II (16). The other part is sent to the transient time. A fixed monostable multivibrator (13) is used, which is triggered by a falling edge; transient time A portion of the signal output from the fixed monostable multivibrator (13) is directly output to AND gate I (15) as the second input signal of AND gate I (15), and the other portion is inverted by NOT gate II (14) and output to AND gate II (16) as the third input signal of AND gate II (16); the output signal of AND gate II (16) is sent to the Start2 channel of TDC (8), and the output of AND gate I (15) is sent to the Stop2 channel of TDC (8).

2. The high anti-interference dual-pulse lidar ranging and communication system as described in claim 1, characterized in that, The TDC (8) includes four channels, namely Start1, Stop1, Start2, and Stop2; among them, channels Start1 and Stop1 are used to measure the flight time of the double-pulse interval signal; channels Start2 and Stop2 are used to measure the double-pulse interval signal, and the time interval between the rising edges of the two pulse signals can be obtained.

3. The execution method of the high anti-interference dual-pulse lidar ranging and communication system as described in claim 1, characterized in that, Specifically, the steps include the following: Step 1: Generation and transmission of dual-pulse interval laser pulses; The MCU (2) in the source transmitter 1 sends the radar IP information to the FPGA (3). The FPGA (3) uses the IP information as a baseband signal to generate a double pulse interval control signal. The double pulse interval time is Tn, which carries the radar IP information. After the FPGA (3) finishes processing, it sends the control signal to the double pulse generation circuit (4). The double pulse generation circuit (4) generates a modulated double pulse signal. The double pulse interval information of this signal is the baseband information to be transmitted. Part of this signal is transmitted to the laser diode pulse emission circuit (5) to transmit the modulated double pulse signal into the channel. The other part is transmitted to the Start1 channel of the time-to-digital converter chip TDC8 as the TDC start signal. Step 2: Dual-pulse interval laser pulse reception and demodulation; The avalanche diode pulse receiving circuit (6) receives the echo signal reflected back from the target being measured. Part of it is sent to the Stop1 channel of the time-to-digital converter chip TDC (8) as the stop signal of the first channel of TDC. The other part is sent to the dual-pulse anti-interference processing module (7) to demodulate the dual-pulse interval signal and transmit the two demodulated pulses to the Start2 and Stop2 channels of TDC (8) respectively. The time difference Tn of the second channel of TDC can be measured. Step 3: Measure the distance and decode the baseband information; TDC(8) will transfer the distance signal The time difference Tn of the second channel is sent back to the FPGA (3), the FPGA (3) transmits the data back to the MCU (2), the MCU (2) processes the data and further calculates the measured distance; on the other hand, the FPGA (3) demodulates the time difference Tn of the second channel according to the modulation method to obtain the baseband signal encoded by the double pulse interval, that is, the IP address of the radar; the system realizes ranging and communication at the same time.

4. The method as described in claim 3, characterized in that, The difference in counting time between Start1 and Stop1 in channel 1 of TDC(8) This refers to the flight time of the dual-pulse laser signal emitted by the source transmitter in the channel, according to the formula: ； Where c is the speed of light, and d is half the distance the dual-pulse laser signal travels in the channel, which is the distance between the target measured by the dual-pulse radar and the lidar, thus realizing the lidar ranging function.

5. The method as described in claim 3, characterized in that, The dual-pulse anti-interference processing module (7) sends a portion of the received dual-pulse interval signal directly to AND gate I (15) and AND gate II (16) without any processing, as the signal to be processed; the other portion is sent to the delay module (10), and further sent to the transient time. Adjustable monostable multivibrator (11), transient time A portion of the adjustable monostable multivibrator (11) is inverted by NOT gate I (12) and sent to AND gate II (16) as the second input signal of AND gate II (16), while the other portion is sent to the transient time. A fixed monostable multivibrator (13) is used. Part of the output of the multivibrator is directly output to AND gate I (15) as the second input signal of AND gate I (15), and the other part is inverted by NOT gate II (14) and output to AND gate II (16) as the third input signal of AND gate II (16).

6. The method as described in claim 3, characterized in that, Transient time The duration of the high-level waveform of the output of the adjustable monostable multivibrator (11) Adjustable; this signal can be used as a transient time. The trigger signal of the fixed monostable multivibrator (13) during the transient time When the output level of the adjustable monostable multivibrator (11) transitions from high to low, the transient time is... A fixed monostable multivibrator (13) is triggered, and the high-level duration of the trigger is... The duration of this high-level signal is fixed and defined as the time window. This signal is ANDed with the double-pulse interval signal through AND gate I (15) to separate the second pulse of the double-pulse interval signal that falls within the time window. Any interference signals outside the time window will be shielded. At the same time, in order to prevent the second pulse from interfering with the output of AND gate II (16), the transient time can be... The output of the fixed monostable multivibrator (13) is inverted to shield the pulse, ensuring that AND gate II (16) only separates the first pulse of the double-pulse interval signal; the first pulse separated by AND gate II (16) is sent to the Start2 channel of TDC (8), and the second pulse separated by AND gate I (15) is sent to the Stop2 channel of TDC (8). The Stop2 channel is measured by TDC (8), and the time difference Tn of the second channel can be measured; the double-pulse anti-interference processing module (7) reasonably sets the transient time of the adjustable monostable multivibrator. Adjust the position of the time window by setting the window width appropriately. This ensures that only the second pulse of the double-pulse interval signal is separated as the input signal for the Stop2 channel, thus shielding all interference signals from outside the window.

7. The method as described in claim 3, characterized in that, The delay time of the delay module (10) is greater than the pulse width of the double pulse interval signal, ensuring that the output of NOT gate I (12) and the double pulse interval signal can be separated into the first pulse of the double pulse interval signal after being ANDed by AND gate II (16).

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