A laser encoded signal processing system and method

Abstract

The application discloses a kind of laser encoding signal processing system and method, and obtains reflected signal to multiple distributed targets of different regions emit laser signal;Laser receiving and collection module carries out set and processing to above-mentioned signal, and executes storage processing to above-mentioned data;Respectively execute synchronous cumulative operation processing to output signal;Signal transmission is carried out after synchronous cumulative operation, and signal decoding module is executed, and decoding operation is executed;The effective information of each target reflected signal is decoded to generate wave gate signal, wherein wave gate locking module is used to generate wave gate signal to extract effective signal for DSP processing module to parse information processing for effective information decoding.The laser encoding signal processing system and method realized according to the application can significantly improve the accuracy of signal processing, improve the identification accuracy and identification efficiency of target information.

Description

Technical Field

[0001] This invention belongs to the field of laser-coded signal processing, and more specifically, it is a laser-coded signal processing system and method. Background Technology

[0002] In the field of measurement, laser emitting devices are generally used to emit lasers to identify targets. However, the laser signals reflected by the target actually contain a lot of information interference and loss. In the above application scenarios, how to achieve a high-speed and high-precision target identification method is an urgent problem to be solved. Summary of the Invention

[0003] Therefore, in response to at least one of the above-mentioned defects or improvement needs of the prior art, the present invention proposes a laser-coded signal processing system and method, which uses a real-time time gate to extract effective information and adds an anti-interference information processing step, thereby significantly improving the accuracy of signal processing.

[0004] This invention discloses a laser-encoded signal processing system, wherein the system is used to receive laser signals reflected back from a corresponding target, and a laser emitting module emits the laser signals, characterized in that the system comprises:

[0005] The laser receiving and acquisition module, the FPGA processing module, and the DSP module are connected in sequence.

[0006] The laser receiving and acquisition module is used to acquire the laser signal reflected back from the corresponding target and perform initial signal processing; the FPGA processing module is used to receive the signal after initial processing and store it, extract the parsed information and upload it to the DSP processing module for analysis.

[0007] The FPGA processing module includes a signal decoding module, a gate locking module, and a pulse extraction module connected in sequence.

[0008] The signal decoding module parses the pulse code information of the laser emission module corresponding to the target from the initially processed signal;

[0009] The signal decoding module extracts valid information containing the corresponding target reflection information from the initially processed signal;

[0010] The gate locking module generates gate information for extracting the parsed information based on the pulse coding information and the valid information. The gate information is generated in real time based on the transmission time of the laser signal reflected back from the corresponding target. The pulse extraction module extracts the parsed information sequentially based on the gate information and uploads it to the DSP processing module.

[0011] Furthermore, the FPGA processing module further includes a signal enhancement and detection module before the signal decoding module, and the initially processed signal undergoes synchronous superposition processing by the signal enhancement and detection module.

[0012] Furthermore, the encoding information of the laser signal emitted by the laser emitting module includes a variable-interval code and a pseudo-random code.

[0013] Furthermore, the DSP processing module includes an anti-high repetition rate interference module and a target position angle analysis module connected in sequence; the anti-high repetition rate interference module is used to process the interference signal from the corresponding target in the parsed information, and the target position angle analysis module performs analysis and calculation to obtain the target's position angle information.

[0014] Furthermore, the starting information of the gate information is synchronized with the initial position of the valid information extracted by the pulse extraction module, and the pulse length information of the gate information corresponds to the decoding length information of the valid information.

[0015] The present invention also discloses a laser-coded signal processing method, characterized in that the method includes the following steps:

[0016] Laser signals are emitted to multiple distributed targets in different regions and reflected signals are obtained, and initial signal processing is performed.

[0017] The initial signal is processed by synchronous accumulation, followed by decoding.

[0018] The pulse code information of the corresponding target is parsed from the initial signal;

[0019] Extract valid information containing the corresponding target reflection information from the initial signal;

[0020] Based on the pulse coding information and the valid information, gate information is generated, and the gate information is generated in real time according to the transmission time of the laser signal reflected back from the corresponding target;

[0021] Based on the gate information, the parsing information is extracted sequentially and the calculation and analysis are performed.

[0022] Furthermore, the decoding operation includes the following steps:

[0023] Extract the laser coding model information from the initial signal, which is the setting information corresponding to the target, and compare it to obtain the current laser coding model information;

[0024] Decoding is performed according to the set number of encoding models and encoding rules.

[0025] Further, the step of generating gate information based on the pulse coding information and the valid information is as follows:

[0026] The position of the last detected valid pulse signal is used as the first synchronization point of the time gate, and the first time gate is set according to the known encoded information length of the valid information.

[0027] The effective information is processed using the first time gate generated. The time of the effective pulse signal detected in the first time gate is used as the synchronization point of the next time gate. The next time gate is then set based on the length of the encoded information in the detected real-time effective pulse signal.

[0028] Furthermore, a high-repetition-rate interference removal algorithm is performed before the step of performing computational analysis.

[0029] Furthermore, prior to performing the decoding operation, a synchronous overlay operation is performed.

[0030] In summary, compared with the prior art, the above-described technical solutions conceived in this invention can achieve the following beneficial effects:

[0031] (1) The laser signal decoding implemented according to the present invention extracts real-time time gate information in the module for extracting and analyzing the signal, and extracts effective information based on the above information, which can improve the accuracy of target information recognition.

[0032] (2) The laser signal decoding implemented according to the present invention can be used to identify targets and can achieve high-speed information processing of multiple targets in the information identification of multiple targets.

[0033] (3) According to the present invention, laser signal decoding is implemented by using a self-gain control circuit based on a logarithmic amplifier to process the initial signal, and a superposition algorithm is performed on the initial signal, and an anti-high repetition frequency interference algorithm is performed to significantly enhance the accuracy of signal processing. Attached Figure Description

[0034] Figure 1 This is a schematic diagram illustrating the target recognition process of the laser-coded signal processing system implemented according to the present invention.

[0035] Figure 2 This is a schematic diagram of the modular structure of the laser-coded signal processing system implemented according to the present invention;

[0036] Figure 3 This is a flowchart illustrating the laser-coded signal processing method implemented according to the present invention.

[0037] Figure 4This is a flowchart illustrating the workflow of the laser signal decoding module in the laser coded signal processing method implemented according to the present invention. Detailed Implementation

[0038] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention. Furthermore, the technical features involved in the various embodiments of this invention described below can be combined with each other as long as they do not conflict with each other.

[0039] like Figure 1 As shown, the laser-coded signal processing system implemented according to the present invention is used to receive a laser signal sent from a laser emitting module to a target and reflected by the target; the laser emitting module includes a pulse coding module for encoding pulses and a laser pointer that emits the pulse code to the laser-coded signal processing system; thus, the reflected signal received by the laser-coded signal processing system contains the pulse-coded signal, therefore, by decoding the pulse-coded signal in the laser-coded signal processing system, the laser-coded signal processing system can identify the corresponding target and the signal reflected by the corresponding target;

[0040] In one specific implementation, the system includes a laser receiving and acquisition module, an FPGA processing module, and a DSP module connected in sequence.

[0041] The laser receiving and acquisition module is used to acquire the laser signal reflected back from the corresponding target and perform initial signal processing; the FPGA processing module is used to receive the signal after initial processing, store it, extract the parsed information, and upload it to the DSP processing module for analysis.

[0042] The FPGA processing module includes a signal decoding module, a gate locking module, and a pulse extraction module connected in sequence.

[0043] The signal decoding module extracts the pulse code information from the laser emission module of the corresponding target from the initially processed signal;

[0044] The signal decoding module extracts valid information containing the corresponding target reflection information from the initially processed signal;

[0045] The gate locking module generates gate information for extracting analytical information based on pulse coding information and valid information. The gate information is generated in real time based on the transmission time of the laser signal reflected back from the corresponding target. The pulse extraction module extracts analytical information sequentially based on the gate information and uploads it to the DSP processing module.

[0046] In one embodiment, the laser signal receiving and acquisition module includes a four-quadrant detector, a logarithmic amplifier-based self-gain control circuit, and a high-speed digital acquisition module.

[0047] The FPGA processing module includes a signal enhancement and detection processing module, a signal decoding module, a gate locking module, and a pulse extraction module;

[0048] The DSP processing module includes an anti-high repetition rate interference module and a target position and angle calculation module.

[0049] The laser emitting module emits laser pulse signals with coded information at a certain position to illuminate the target. The laser coded signal processing system receives the pulse signal reflected back from the target. This laser signal forms a light spot on the photosensitive surface of the four-quadrant detector in the laser signal receiving and acquisition module. The light spot signal is converted into four voltage signals containing target orientation information. After passing through a logarithmic amplifier-based self-gain amplifier circuit and high-speed A / D acquisition, the four voltage signals are converted into digital signals that can be processed by the FPGA and sent to the FPGA processing module.

[0050] The FPGA processing module receives the signal emitted by the laser signal receiving and acquisition module, and enhances and detects the weak pulse signal after reflection according to the designed signal processing algorithm. The signal decoding module decodes the signal and completes code matching. The gate locking module generates the gate control signal for signal extraction. The pulse extraction module extracts the effective signal according to the gate control signal and sends the extracted effective signal to the DSP processing module for data processing.

[0051] The DSP processing module performs anti-high repetition rate interference algorithm processing on the above effective signals and uses a positioning algorithm to calculate the offset between the optical axis of the equipment and the target line of sight (yaw angle and pitch angle), wherein the above equipment has the above laser coded signal processing system.

[0052] In the initial stage of reflected signal emission and transmission, the enhancement and detection processing module, where the target illuminated by the laser emission module is far from the equipment and the pulse signal received by the four-quadrant detector is weak, needs to enhance the received pulse signal to quickly identify the target. In this embodiment, the enhancement and detection processing module uses a synchronous accumulation method to initially enhance the signal to noise ratio of the pulse signal. This synchronous accumulation method involves repeatedly measuring the periodic signal and then accumulating the measured signal data according to the requirements of the same position and phase. Since the signal has a periodic pattern, it becomes increasingly larger after accumulation, while noise is random and partially cancels out or, during the superposition process, the amplitude ratio of the periodic signal significantly exceeds that of the noise signal, making the extraction of the periodic signal more accurate. This achieves the goal of improving the signal-to-noise ratio.

[0053] In fact, the signal reflected back from the target also includes the target's specific interference signal. This signal is a high repetition rate interference signal, which may drown out the already weak effective signal pulse reflected from the target. Therefore, the laser emission module involved in this invention actually includes two types of laser coded pulses, namely pseudo-random code and variable interval code. This can achieve the purpose of distinguishing multiple targets in the same area by setting different pulse codes. By identifying the set coding method, the effective target can be identified, thereby improving the system's anti-interference capability.

[0054] The FPGA processing module and DSP processing module use gate control and anti-high repetition frequency interference algorithms for processing. In order to ensure the speed and accuracy of the operation, an architecture of FPGA module plus DSP module is adopted.

[0055] The FPGA processing module includes a gate-locking module for generating a time-gated gate and sending it to the pulse extraction module. The time-gated gate generation and extraction process implemented in this invention includes the following steps:

[0056] (1) Obtain the laser coding model information in the laser emission module. The above coding information is the set and known information corresponding to the target.

[0057] (2) The signal decoding module decodes the signal processed by the signal enhancement and detection module, obtains the current effective pulse signal, and obtains the position information of the effective pulse. Based on the above code pattern information and the effective pulse position information, it generates the predicted time period of the next effective pulse. The above time period is used as the time gate signal. The above gate signal is used to generate and predict the next time gate. In a preferred embodiment, the time gate is updated in real time according to a certain time period, so that when predicting the time gate, more gate signals generated by real-time acquired signals are used, so that the signal processing accuracy of the DSP processing module is higher.

[0058] Time-gating technology can improve the anti-interference capability of equipment. Based on the known laser coding pattern information and the pulse position information detected and identified by the laser coding signal processing system, the time period for the next effective pulse signal to arrive at the laser coding signal processing system is predicted, and the time gate is set accordingly. The signal processing system only processes the data within the set time gate, while shielding the interference data outside the time gate. This reduces the computational burden of the signal processing system and improves the anti-interference capability of the laser coding signal processing system.

[0059] Because fixed gates use only one time synchronization point to predict the positions of all subsequent gates, they suffer from accumulated errors. Real-time gates, on the other hand, use multiple time synchronization points, constantly adjusting the position of the next time gate based on the detected effective pulse position within the gate, thus eliminating accumulated errors. Therefore, this system employs real-time gate control. When the laser-encoded signal processing system successfully decodes the signal, the position of the last detected effective pulse signal is used as the first synchronization point for the time gate, and the first time gate is set based on the known encoding information. Then, the time of the detected effective pulse signal within the time gate is used as the synchronization point for the next time gate, and the next time gate is set accordingly.

[0060] like Figure 3 As shown in the figure, the present invention also discloses a laser-coded signal processing method, characterized in that the method includes the following steps:

[0061] Laser signals are emitted to multiple distributed targets in different regions and reflected signals are obtained, and initial signal processing is performed.

[0062] The initial signal is processed by synchronous accumulation, followed by decoding.

[0063] Extract the pulse code information of the corresponding target from the initial signal;

[0064] Extract the effective information containing the corresponding target reflection information from the initially processed signal;

[0065] The gate information is generated based on the pulse code information and valid information. The gate information is generated in real time based on the transmission time of the laser signal reflected back from the corresponding target.

[0066] Based on the gate information, the parsing information is extracted sequentially and the calculation and analysis are performed.

[0067] Specifically, the process of receiving, filtering, acquiring, detecting, decoding, extracting, and processing laser signals includes the following steps.

[0068] Step S1: Initialization steps for the laser encoding signal processing system corresponding to the device; Initialize the system, check whether each module of the laser encoding signal processing system has started normally, complete the initialization of each part, and enable the laser encoding signal processing system to start running in a controllable state of each working module.

[0069] Step S2: Emit laser signals to multiple distributed targets in different areas and obtain reflected signals, and perform photoelectric conversion; the laser emission module illuminates the signals with coded information onto multiple targets in different areas, and the laser signals reflected back from the targets are first converted into four voltage signals by the four-quadrant detector in the laser coded signal processing system;

[0070] Step S3: The laser receiving and acquisition module acquires and processes the signal sent by the laser emitting module and sends the data to the FPGA processing module for storage; the four-quadrant detector converts the detected optical signal into four synchronous voltage signals, which then pass through a self-gain control circuit composed of a logarithmic amplifier, and then through a high-precision acquisition system to acquire the four data synchronously. The large amount of acquired data is then transferred to the FIFO memory in the FPGA processing module to ensure that no data is lost during processing.

[0071] Step S4: The FPGA processing module performs synchronous accumulation operations on the four data channels stored in the FPGA processing module; the signal enhancement and detection processing module performs a synchronous accumulation operation on the four synchronous signals acquired, improves the signal-to-noise ratio of the pulse signal, and improves the detection accuracy of the signal, so as to quickly and accurately detect the effective pulse signal in the next signal processing step, and provide a basis for further decoding.

[0072] Step S5: The signal after synchronous accumulation operation in the above signal enhancement and detection processing module is transmitted to the signal decoding module for decoding operation;

[0073] The above decoding operation further includes the following steps, such as... Figure 4 The image shown illustrates one implementation of the decoding operation:

[0074] S51: Extract the laser coding model information from the signal after synchronous accumulation operation. The above coding information is the set and known information corresponding to the target. Compare the known and set information stored in the memory of the FPGA processing module with the collected information to obtain the laser coding model information.

[0075] S52: Decode the information according to the set number and rules of the coding models. The laser coding model information includes at least two coding model information. Based on the different characteristics of the two different code types, variable interval code and pseudo-random code, the signal period of the variable interval code changes regularly according to the set rules, while the signal period of the pseudo-random code is non-cyclic. According to the above two different coding methods, corresponding decoding strategies are designed. In one implementation, for the variable interval code, decoding can be achieved by measuring its period interval. For the pseudo-random code, the sliding correlation matching method is used to complete the decoding, realizing the rapid identification of the target and providing a basis for the next step of gate control.

[0076] Step S6: Generate a gate signal for decoding the effective information of each target reflection signal. The gate locking module is used to generate the gate signal for decoding the effective information. This system adopts real-time gate control. When the equipment signal processing system successfully decodes, the position of the last detected effective pulse signal is used as the first synchronization point of the time gate. The first time gate is set according to the known encoding information of the effective information (code length of the effective information).

[0077] The information is processed using the first generated time gate. Then, the time of the valid pulse signal detected within the time gate is used as the synchronization point of the next time gate and the known encoded information in the valid information. The next time gate is then set, and the pulse signal is extracted during the gate opening time. In this way, the pulse extraction module completes the extraction of valid information within the gate.

[0078] Step S7: Data Extraction Analysis; The data within the time gate is transmitted to the DSP processing module for high repetition rate interference (HRRI) processing. The DSP processes the data within the time gate, first further processing it with an HRI algorithm to remove HRI interference and identify the valid pulse signal. For the classic four-quadrant detector positioning algorithm, linearization processing has certain errors and can only extract partial information. To address this, a second-order Taylor expansion is performed on the extracted data, improving accuracy and effective data utilization. The elevation and deflection angles relative to the target are calculated, and the calculated information is sent to the corresponding equipment in the laser-coded signal processing system.

[0079] The description in this specification is merely illustrative of the invention. Those skilled in the art can make various modifications or additions to the specific embodiments described or use similar methods to replace them, as long as they do not deviate from the content of this specification or exceed the scope defined in the claims, they should all fall within the protection scope of this invention.

Claims

1. A laser-encoded signal processing system, wherein the system is used to receive laser signals reflected back from a corresponding target, and a laser emitting module emits the laser signals, characterized in that, The system includes: The laser receiving and acquisition module, the FPGA processing module, and the DSP module are connected in sequence. The laser receiving and acquisition module is used to acquire the laser signal reflected back from the corresponding target and perform initial signal processing; the FPGA processing module is used to receive the signal after initial processing and store it, extract the parsed information and upload it to the DSP processing module for analysis. The FPGA processing module includes a signal decoding module, a gate locking module, and a pulse extraction module connected in sequence. The signal decoding module parses the pulse code information of the laser emission module corresponding to the target from the initially processed signal; The signal decoding module extracts valid information containing the corresponding target reflection information from the initially processed signal; The gate locking module generates gate information for extracting the parsed information based on the pulse coding information and the valid information. The gate information is generated in real time based on the transmission time of the laser signal reflected back from the corresponding target. The pulse extraction module extracts the parsed information sequentially based on the gate information and uploads it to the DSP processing module.

2. The laser-coded signal processing system according to claim 1, characterized in that, The FPGA processing module further includes a signal enhancement and detection module before the signal decoding module, and the initially processed signal undergoes synchronous superposition processing by the signal enhancement and detection module.

3. The laser-coded signal processing system according to claim 1 or 2, characterized in that, The encoded information of the laser signal emitted by the laser emitting module includes variable-interval code and pseudo-random code.

4. The laser-coded signal processing system according to claim 3, characterized in that, The DSP processing module includes an anti-high repetition rate interference module and a target position angle analysis module connected in sequence; the anti-high repetition rate interference module is used to process the interference signal from the corresponding target in the parsed information, and the target position angle analysis module performs analysis and calculation to obtain the target's position angle information.

5. The laser-coded signal processing system according to claim 1, characterized in that, The starting information of the gate information is synchronized with the initial position of the effective information extracted by the pulse extraction module, and the pulse length information of the gate information corresponds to the decoding length information of the effective information.

6. A laser-coded signal processing method, characterized in that, The method includes the following steps: Laser signals are emitted to multiple distributed targets in different regions and reflected signals are obtained, and initial signal processing is performed. The initial signal is processed by synchronous accumulation, followed by decoding. The pulse code information of the corresponding target is parsed from the initial signal; Extract valid information containing the corresponding target reflection information from the initial signal; Based on the pulse coding information and the valid information, gate information is generated, and the gate information is generated in real time according to the transmission time of the laser signal reflected back from the corresponding target; Based on the gate information, the parsing information is extracted sequentially and the calculation and analysis are performed.

7. The laser-coded signal processing method as described in claim 6, characterized in that, The decoding operation includes the following steps: Extract the laser coding model information from the initial signal, which is the setting information corresponding to the target, and compare it to obtain the current laser coding model information; Decoding is performed according to the set number of encoding models and encoding rules.

8. The laser-coded signal processing method as described in claim 7, characterized in that, The steps for generating gate information based on the pulse coding information and the valid information are as follows: The position of the last detected valid pulse signal is used as the first synchronization point of the time gate, and the first time gate is set according to the known encoded information length of the valid information. The effective information is processed using the first time gate generated. The time of the effective pulse signal detected in the first time gate is used as the synchronization point of the next time gate. The next time gate is then set based on the length of the encoded information in the detected real-time effective pulse signal.

9. The laser-coded signal processing method as described in claim 8, characterized in that, Before performing the computational analysis step, a high-repetition-rate interference removal algorithm is executed.

10. The laser-coded signal processing method as described in claim 9, characterized in that, Prior to performing the decoding operation, a synchronous overlay operation is further performed.

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