Multifunctional telescope type range finder calibration device based on FPGA

Abstract

The invention discloses a multifunctional telescope type range finder calibration device based on an FPGA (Field Programmable Gate Array), relates to the technical field of range finding calibration, and solves the problem that the traditional calibration device cannot simulate the intensity of received signals at different distances and in different weather, so that the calibration precision deviation is too large. The range finder calibration device comprises a power supply module, a display reminding module, a control module and a calibration module. The power supply module comprises a power supply unit, a variable energy charging power supply, an LD driving unit and a high-voltage bias unit; the control module comprises an FPGA control unit; the laser comprises a laser sensor, an optical assembly and a laser attenuation sheet; the calibration module comprises an APD pre-amplification unit, a voltage comparator and a threshold adjusting unit; dynamically adjusting the calibration module by using the pulse signal model library through the FPGA control unit so as to complete the calibration of the multifunctional telescope type range finder; picosecond-level signal delay is carried out through the high-performance FPGA control unit, the laser flight time is accurately simulated, different received signal strengths can be truly simulated under different distances, and the calibration precision is improved.

Description

Technical Field

[0001] The invention relates to the technical field of distance measurement and calibration, and in particular to a multifunctional telescope-type distance meter calibration device based on FPGA. Background Art

[0002] Telescope rangefinder is a distance measuring instrument that combines telescope system and laser rangefinder, which integrates distance measurement and observation. It has the advantages of wide measurement range and high accuracy. The traditional laser rangefinder telescope simulation distance calibration is generally carried out using a standard length baseline field established outdoors. The traditional method not only requires a large amount of space, but is also easily affected by many factors such as environment, weather, temperature, etc.; especially as the distance measurement increases, it will take up a large amount of space, which is not conducive to mass production of products.

[0003] The existing indoor calibration device of the laser ranging telescope uses optical fibers of different lengths to simulate different distances for calibration. However, since there is a certain error in the length of each roll of processed optical fiber, there is an error in the actual propagation distance of light in the optical fiber. When replacing the optical fiber, it is also necessary to re-measure the actual propagation distance of light in the optical fiber and readjust the calibration distance parameters, which is troublesome to operate.

[0004] Patent No. CN2023115608019 discloses a laser rangefinder distance calibration device and method thereof, which solves the problem in the prior art that it is inconvenient to adjust the verticality of the calibration device when the rangefinder is calibrated. The above invention includes a rangefinder clamping mechanism and a target position. The above invention also includes a target moving assembly, a reversing mechanism arranged on the target moving assembly, a collimated laser emitter arranged on the reversing mechanism, and a microprocessor. A photoelectric position sensor is arranged on the target position, and the target position is slidably arranged on the target moving assembly. The rangefinder clamping mechanism is installed on the reversing mechanism, and the microprocessor is electrically connected to the target moving assembly, the reversing mechanism, the collimated laser emitter, and the photoelectric position sensor respectively. The above invention cooperates with the reversing mechanism, the collimated laser emitter and the photoelectric position sensor. The collimated laser emitter and the photoelectric position sensor can provide a reference when adjusting the rangefinder clamping mechanism, and at the same time adjust the angle posture of the rangefinder clamping mechanism through the reversing mechanism.

[0005] Patent No. CN2022115977292 discloses a laser rangefinder deviation calibration device and method, which belongs to the field of photoelectric distance measurement technology. The device includes a controller, a three-dimensional turntable, a laser rangefinder installed on the three-dimensional turntable and used for calibration, and a driving mechanism, a cross target, a laser receiver and an image acquisition unit. The cross target is provided with a fine adjustment area and a coarse adjustment area surrounding the fine adjustment area. The fine adjustment area is located at the center of the cross target, and the fine adjustment area includes a cross target area and a near target area with different laser reflection coefficients; the method includes calculating the azimuth offset difference based on the position correction of the laser spot, which is then used for subsequent actual laser measurement data correction. The technical solution of the above invention improves the measurement accuracy.

[0006] Although the above patents simply use optical fiber as the medium for laser transmission, they can only simulate the flight time of the laser, but cannot simulate the strength of the received signal at different distances and in different weather conditions, which has a great impact on the calibration accuracy. In addition, if a new calibration distance is added, it is necessary to add optical fiber of the corresponding distance again, which requires a large adjustment of the calibration tooling, affecting product production efficiency. Summary of the invention

[0007] The purpose of the present invention is to provide a multifunctional telescope rangefinder calibration device based on FPGA, which can dynamically adjust the calibration module using a pulse signal model library through an FPGA control unit to complete the calibration of the multifunctional telescope rangefinder; through a high-performance FPGA control unit, picosecond signal delay is performed to accurately simulate the laser flight time, and then different laser pulse beam intensities can be truly simulated at different distances to improve the calibration accuracy.

[0008] The present invention utilizes the following technical solutions:

[0009] A multifunctional telescope-type rangefinder calibration device based on FPGA, comprising a power supply module, a display reminder module, a control module and a calibration module; wherein:

[0010] The power module includes a power supply unit and a high voltage bias unit;

[0011] The power module provides power to the display reminder module and the control module through the power supply unit, and provides bias high voltages of different voltage levels to the calibration module through the high voltage bias unit to ensure the normal operation of the rangefinder calibration device;

[0012] The display reminder module includes a key unit, a buzzer and an LCD display screen;

[0013] The display reminder module realizes human-machine operation control through the key unit, sets and displays calibration parameters through the LCD display screen, and uses the buzzer to correct the laser energy of the laser and the simulated distance of the ranging telescope to the FPGA control unit, thereby completing the real-time prompt of the operating status of the multi-functional telescope rangefinder;

[0014] The control module includes an FPGA control unit; the control module dynamically adjusts the calibration module by using a pulse signal model library through the FPGA control unit to complete the calibration of the multifunctional telescope rangefinder;

[0015] The calibration module includes an APD preamplifier unit, a voltage comparator, a threshold adjustment unit, a variable charging power supply, an LD drive unit, a laser sensor, an optical component and a laser attenuation sheet;

[0016] The calibration module controls the laser point light source emitted by the laser sensor through a variable charging power supply and an LD driving unit, and converts the laser point light source into parallel light through an optical component, and transmits it to the range-finding telescope to be calibrated through a first laser attenuation plate. The laser pulse beam emitted by the range-finding telescope to be calibrated is transmitted to the optical component through a second laser attenuation plate, and is collected and processed by an APD preamplifier unit, and then converted into a pulse voltage signal and sent to a voltage comparator; the voltage comparator converts the pulse voltage signal into a square wave pulse signal, and sends it to the control module for collecting and processing the square wave pulse signal; the control module also provides bias high voltages of different voltage levels for the APD preamplifier unit by controlling the high voltage bias unit; the control module also sets different voltage thresholds for the voltage comparator according to the square wave pulse signal through a threshold adjustment unit;

[0017] The control module is respectively connected to the calibration module and the display reminder module through a communication serial port or a signal line; the power supply module is respectively connected to the display reminder module, the calibration module and the control module through an electrical line.

[0018] Preferably, the operating states include starting calibration, successful calibration and failed calibration; a variable charging power supply for infinitely controlling the laser point light source emitted by the laser sensor to simulate the intensity of the laser point light source reflected from targets with different reflectivity or in different weather conditions; an LD driving unit for controlling the laser sensor; a laser sensor for emitting a laser point light source; an optical component for converting the laser point light source emitted by the laser sensor into laser parallel light; a laser attenuation plate for attenuating the processed laser parallel light; an FPGA control unit for driving the laser sensor to output a laser point light source with an arbitrary delay time, thereby simulating the laser flight time at different distances; an APD preamplifier unit for collecting and processing the laser pulse beam emitted by the ranging telescope to be calibrated; a high-voltage bias unit for providing a bias high voltage of different voltage levels to the APD preamplifier unit; a voltage comparator for converting the collected laser pulse beam into a square wave pulse signal; and a threshold adjustment unit for setting different voltage thresholds for the voltage comparator.

[0019] Preferably, the steps of collecting and processing the laser pulse beam emitted by the range-finding telescope to be calibrated by the APD preamplifier unit are:

[0020] S1: The range-finding telescope to be calibrated emits a laser pulse beam, which is attenuated by the second laser attenuation plate and focused to the APD preamplifier unit through the optical component;

[0021] S2: The APD preamplifier unit absorbs photons in the attenuated laser pulse beam to generate electron-hole pairs;

[0022] S3: Under high voltage electric field, electron-hole pairs multiply through avalanche effect, generating current pulse signals;

[0023] S4: The APD preamplifier unit amplifies the current pulse signal using a signal amplification circuit;

[0024] S5: The APD preamplifier unit converts the amplified current pulse signal into a pulse voltage signal using a signal conversion circuit;

[0025] S6: The APD preamplifier unit uses a filter circuit to remove the noise signal in the pulse voltage signal.

[0026] Preferably, the steps of the FPGA control unit dynamically adjusting the calibration module using the pulse signal model library are:

[0027] A: The voltage comparator of the calibration module receives the pulse voltage signal of the APD preamplifier unit and converts the pulse voltage signal into a square wave pulse signal using a square wave generator;

[0028] B: The voltage comparator extracts the real-time amplitude V1 of the square wave pulse signal, and compares the real-time amplitude V1 with the voltage threshold V0 set in the threshold adjustment unit;

[0029] C: If V1≠V0, the FPGA control unit corrects the environmental impact factor and records the real-time amplitude V1 and voltage threshold V0; if V1=V0, the FPGA control unit controls the variable charging power supply to adjust the delay time of the laser point light source emitted by the laser, thereby adjusting the simulated distance of the ranging telescope;

[0030] D: The feature extraction layer of the pulse signal model library extracts features from the real-time amplitude V1, voltage threshold V0, environmental impact factors, delay time and simulated distance of the ranging telescope to obtain simulated feature values;

[0031] E: The learning and training layer of the pulse signal model library performs several iterative training on the simulated eigenvalues ​​to obtain the simulated feature weight matrix;

[0032] F: The output update layer and global loss function of the pulse signal model library perform global update optimization on the simulated feature weight matrix to identify and output the delay time corresponding to the simulated distances of different ranging telescopes;

[0033] G: The FPGA control unit corrects the laser energy of the laser and the simulated distance of the ranging telescope according to the delay time corresponding to different simulated distances of the ranging telescope, thereby completing the calibration of the multi-functional telescope rangefinder.

[0034] Preferably, the feature extraction layer includes 2 3×3 convolutional layers, 3 7×7 convolutional layers, 2 convolutional blocks consisting of 3×1 convolutional layers and 1×3 convolutional layers, and 2 5×5 average pooling layers; the learning and training layer includes 2 serial 3×3 convolutional layers, 2 5×5 adaptive pooling layers, 1 InceptionV3 block, 1 InceptionV4 block, 1 5×5 convolutional layer and 1 ReLU activation function; the output update layer includes 3 3×3 convolutional layers, 2 5×5 convolutional layers, 2 random dropout layers and 2 fully connected layers.

[0035] Preferably, the FPGA control unit corrects the laser energy of the laser and the simulated distance of the ranging telescope, and then completes the calibration steps of the multifunctional telescope rangefinder as follows:

[0036] G1: Place the rangefinder telescope to be calibrated on the test station, connect the power supply and communication interface to the rangefinder calibration device normally, and select the calibration parameters through the LCD display; the calibration parameters include the model to be calibrated, the simulated distance of the rangefinder telescope, the weather mode and the reflectivity of the target object;

[0037] G2: Click on automatic calibration, and the FPGA control unit sends a calibration start command and the simulated distance of the telescope to be calibrated through the communication serial port;

[0038] G3: After receiving the calibration start command and the simulated distance of the ranging telescope, the ranging function is automatically started, and the laser sensor emits a laser pulse beam;

[0039] G4: The rangefinder calibration device collects and processes the laser pulse beam through the APD preamplifier unit, voltage comparator and FPGA controller unit to form a pulse voltage signal;

[0040] G5: After receiving the pulse voltage signal, the FPGA control unit forms a corresponding delay time according to the simulated distance of the ranging telescope and emits a laser pulse beam. The FPGA control unit adjusts the emission energy of the laser sensor through a variable charging power supply to simulate the echo pulse signals of different ranging telescope simulated distances and different target reflectivity;

[0041] G6: After receiving the echo pulse signal, the rangefinder telescope to be calibrated calculates the actual distance of the rangefinder telescope, and calibrates the simulated distance of the rangefinder telescope according to the actual distance of the rangefinder telescope and the simulated distance of the rangefinder telescope. After the calibration is successful, the rangefinder telescope to be calibrated sends a calibration success signal to the FPGA control unit, and the LCD screen displays the calibration success, and the buzzer sounds to prompt;

[0042] G7: After the first ranging telescope simulated distance is calibrated successfully, the FPGA control unit sends a command to start calibrating the second ranging telescope simulated distance to the ranging telescope to be calibrated through the communication serial port, and then calibrates the simulated distances of all ranging telescopes in sequence according to steps G3 to G7.

[0043] Preferably, the calibration module also includes a peak intensity detection unit; the peak intensity detection unit is used to detect the relative energy of the laser emitted by the ranging telescope to be calibrated to obtain the laser energy peak value emitted by the ranging telescope to be calibrated; and use the laser energy peak value as the characteristic parameter of the pulse signal model library to obtain a new simulation feature weight matrix.

[0044] Preferably, the peak intensity detection unit receives the pulse voltage signal of the APD preamplifier unit and is electrically connected to the APD preamplifier unit; the peak intensity detection unit inputs the laser energy peak value of the detected pulse voltage signal into the FPGA control unit, and displays the laser energy peak value on the LCD liquid crystal display screen, so that the test personnel can evaluate the quality of the laser pulse beam of the ranging telescope to be calibrated, thereby eliminating defective products.

[0045] The present invention uses a pulse signal model library to dynamically adjust the calibration module through an FPGA control unit to complete the calibration of a multifunctional telescope rangefinder; a high-performance FPGA control unit is used to perform picosecond signal delay to accurately simulate the laser flight time, thereby truly simulating different laser pulse beam intensities at different distances and improving the calibration accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or related technologies, the drawings required for use in the embodiments or related technical descriptions are briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying creative work.

[0047] Figure 1 The multifunctional telescope type FPGA control unit corrects the laser energy of the laser and the simulated distance of the ranging telescope, thereby completing the scheme 1 flow chart of the multifunctional telescope type rangefinder;

[0048] Figure 2 The multifunctional telescope FPGA control unit corrects the laser energy of the laser and the simulated distance of the ranging telescope, thereby completing the scheme 2 flow chart of the multifunctional telescope rangefinder. DETAILED DESCRIPTION

[0049] The present invention is described in detail below with reference to the accompanying drawings and embodiments:

[0050] like Figure 1-Figure 2 As shown, the multifunctional telescope-type rangefinder calibration device based on FPGA of the present invention comprises a power supply module, a display reminder module, a control module and a calibration module; wherein,

[0051] The power module includes a power supply unit and a high voltage bias unit;

[0052] The power module provides power to the display reminder module and the control module through the power supply unit, and provides bias high voltages of different voltage levels to the calibration module through the high voltage bias unit to ensure the normal operation of the rangefinder calibration device;

[0053] In the present invention, the high voltage bias unit is a high voltage bias circuit;

[0054] The display reminder module includes a key unit, a buzzer and an LCD display screen;

[0055] The display reminder module realizes human-machine operation control through the key unit, sets and displays calibration parameters through the LCD display screen, and uses the buzzer to correct the laser energy of the laser and the simulated distance of the ranging telescope to the FPGA control unit, thereby completing the real-time prompt of the operating status of the multi-functional telescope rangefinder;

[0056] The control module includes an FPGA control unit; the control module dynamically adjusts the calibration module by using a pulse signal model library through the FPGA control unit to complete the calibration of the multifunctional telescope rangefinder;

[0057] The calibration module includes an APD preamplifier unit, a voltage comparator, a threshold adjustment unit, a variable charging power supply, an LD drive unit, a laser sensor, an optical component and a laser attenuation sheet;

[0058] The calibration module controls the laser point light source emitted by the laser sensor through a variable charging power supply and an LD driving unit, and converts the laser point light source into parallel light through an optical component, and transmits it to the range-finding telescope to be calibrated through a first laser attenuation plate. The laser pulse beam emitted by the range-finding telescope to be calibrated is transmitted to the optical component through a second laser attenuation plate, and is collected and processed by an APD preamplifier unit, and then converted into a pulse voltage signal and sent to a voltage comparator; the voltage comparator converts the pulse voltage signal into a square wave pulse signal, and sends it to the control module for collection and processing of the square wave pulse signal; the control module also controls the high-voltage bias unit to provide bias high voltages of different voltage levels for the APD preamplifier unit; the control module also sets different voltage thresholds for the voltage comparator according to the square wave pulse signal through a threshold adjustment unit;

[0059] The control module is connected to the calibration module and the display reminder module respectively through a communication serial port or a signal line; the power module is connected to the display reminder module, the calibration module and the control module respectively through an electrical line;

[0060] In the present invention, the operating states include starting calibration, successful calibration and failed calibration; a variable charging power supply is used to perform stepless control on the laser point light source emitted by the laser sensor to simulate the intensity of the laser point light source reflected by targets with different reflectivity or in different weather conditions; an LD driving unit is used to control the laser sensor; a laser sensor is used to emit a laser point light source; an optical component is used to convert the laser point light source emitted by the laser sensor into laser parallel light; a laser attenuation plate is used to attenuate the processed laser parallel light; an FPGA control unit is used to drive the laser sensor to output a laser point light source with an arbitrary delay time, thereby simulating the laser flight time at different distances; an APD preamplifier unit is used to collect and process the laser pulse beam emitted by the range-finding telescope to be calibrated; a high-voltage bias unit is used to provide a bias high voltage of different voltage levels for the APD preamplifier unit; a voltage comparator is used to convert the collected laser pulse beam into a square wave pulse signal; a threshold adjustment unit is used to set different voltage thresholds for the voltage comparator;

[0061] In the present invention, the steps of collecting and processing the laser pulse beam emitted by the range-finding telescope to be calibrated by the APD preamplifier unit are as follows:

[0062] S1: The range-finding telescope to be calibrated emits a laser pulse beam, which is attenuated by the second laser attenuation plate and focused to the APD preamplifier unit through the optical component;

[0063] S2: The APD preamplifier unit absorbs photons in the attenuated laser pulse beam to generate electron-hole pairs;

[0064] S3: Under high voltage electric field, electron-hole pairs multiply through avalanche effect, generating current pulse signals;

[0065] S4: The APD preamplifier unit amplifies the current pulse signal using a signal amplification circuit;

[0066] S5: The APD preamplifier unit converts the amplified current pulse signal into a pulse voltage signal using a signal conversion circuit;

[0067] S6: The APD preamplifier unit uses a filter circuit to remove the noise signal in the pulse voltage signal;

[0068] In the present invention, the steps of the FPGA control unit dynamically adjusting the calibration module using the pulse signal model library are as follows:

[0069] A: The voltage comparator of the calibration module receives the pulse voltage signal of the APD preamplifier unit and converts the pulse voltage signal into a square wave pulse signal using a square wave generator;

[0070] B: The voltage comparator extracts the real-time amplitude V1 of the square wave pulse signal, and compares the real-time amplitude V1 with the voltage threshold V0 set in the threshold adjustment unit;

[0071] C: If V1≠V0, the FPGA control unit corrects the environmental impact factor and records the real-time amplitude V1 and voltage threshold V0; if V1=V0, the FPGA control unit controls the variable charging power supply to adjust the delay time of the laser point light source emitted by the laser, thereby adjusting the simulated distance of the ranging telescope;

[0072] In this embodiment, the environmental impact factor is the pulse delay coefficient of the laser pulse in different weather modes;

[0073] D: The feature extraction layer of the pulse signal model library extracts features from the real-time amplitude V1, voltage threshold V0, environmental impact factors, delay time and simulated distance of the ranging telescope to obtain simulated feature values;

[0074] E: The learning and training layer of the pulse signal model library performs several iterative training on the simulated eigenvalues ​​to obtain the simulated feature weight matrix;

[0075] F: The output update layer and global loss function of the pulse signal model library perform global update optimization on the simulated feature weight matrix to identify and output the delay time corresponding to the simulated distances of different ranging telescopes;

[0076] G: The FPGA control unit corrects the laser energy of the laser and the simulated distance of the ranging telescope according to the delay time corresponding to the simulated distance of the different ranging telescopes, thereby completing the calibration of the multifunctional telescope rangefinder;

[0077] In the present invention, the feature extraction layer includes two 3×3 convolutional layers, three 7×7 convolutional layers, two convolutional blocks consisting of a 3×1 convolutional layer and a 1×3 convolutional layer, and two 5×5 average pooling layers;

[0078] In this embodiment,

[0079]

[0080] Among them, Model 1 represents the feature extraction layer, represents a 5×5 average pooling layer with a stride of 2, represents two 1×3 convolutional layers with a stride of 1 connected in series, represents two 3×1 convolutional layers with a stride of 1 connected in series, represents a 3×3 convolutional layer with a stride of 2, represents three 7×7 convolutional layers with a stride of 1 connected in series, T1 represents the delay time, L represents the simulated distance of the ranging telescope, and α represents the environmental impact factor;

[0081] The learning training layers include 2 serial 3×3 convolutional layers, 2 5×5 adaptive pooling layers, 1 InceptionV3 block, 1 InceptionV4 block, 1 5×5 convolutional layer, and 1 ReLU activation function;

[0082] In this embodiment,

[0083]

[0084] Among them, Model 2 Represents the learning training layer, AutoPool 5×5 2 () represents two 5×5 adaptive pooling layers in series, represents a 5×5 convolutional layer with a stride of 2, represents two 3×3 convolutional layers with a stride of 2 in series;

[0085] The output update layer includes three 3×3 convolutional layers, two 5×5 convolutional layers, two random dropout layers, and two fully connected layers;

[0086]

[0087] Among them, Model 3 represents the output update layer, Loss represents the global loss function, FCL 2 () indicates two fully connected layers in series, Dropout 2 () represents two random dropout layers in series, represents multiple addition operations, σ represents the number of iterative training layers, G represents the quantization function, μ1 represents the calculation accuracy coefficient, and B σ represents the iterative training loss function of each layer, μ2 represents the preset optimization weight coefficient, E σ Indicates the optimization efficiency of each layer’s iterative training;

[0088] In the present invention, the FPGA control unit corrects the laser energy of the laser and the simulated distance of the ranging telescope, and then completes the calibration steps of the multifunctional telescope rangefinder as follows:

[0089] G1: Place the rangefinder telescope to be calibrated on the test station, connect the power supply and communication interface to the rangefinder calibration device normally, and select the calibration parameters through the LCD display; the calibration parameters include the model to be calibrated, the simulated distance of the rangefinder telescope, the weather mode and the reflectivity of the target object;

[0090] G2: Click on automatic calibration, and the FPGA control unit sends a calibration start command and the simulated distance of the telescope to be calibrated through the communication serial port;

[0091] G3: After receiving the calibration start command and the simulated distance of the ranging telescope, the ranging function is automatically started, and the laser sensor emits a laser pulse beam;

[0092] G4: The rangefinder calibration device collects and processes the laser pulse beam through the APD preamplifier unit, voltage comparator and FPGA controller unit to form a pulse voltage signal;

[0093] G5: After receiving the pulse voltage signal, the FPGA control unit forms a corresponding delay time according to the simulated distance of the ranging telescope and emits a laser pulse beam. The FPGA control unit adjusts the emission energy of the laser sensor through a variable charging power supply to simulate the echo pulse signals of different ranging telescope simulated distances and different target reflectivity;

[0094] In this embodiment, according to the set calibration parameters, the FPGA control unit can simulate the situation of outputting multiple echo pulse signals at the same time;

[0095] G6: After receiving the echo pulse signal, the rangefinder telescope to be calibrated calculates the actual distance of the rangefinder telescope, and calibrates the simulated distance of the rangefinder telescope according to the actual distance of the rangefinder telescope and the simulated distance of the rangefinder telescope. After the calibration is successful, the rangefinder telescope to be calibrated sends a calibration success signal to the FPGA control unit, and the LCD screen displays the calibration success, and the buzzer sounds to prompt;

[0096] G7: After the first ranging telescope simulated distance is calibrated successfully, the FPGA control unit sends a command to start calibrating the second ranging telescope simulated distance to the ranging telescope to be calibrated through the communication serial port, and then calibrates the simulated distances of all ranging telescopes in sequence according to steps G3 to G7.

[0097] In the present invention, the calibration module also includes a peak intensity detection unit; the peak intensity detection unit is used to detect the relative energy of the laser emitted by the ranging telescope to be calibrated to obtain the laser energy peak value; and the laser energy peak value is used as the characteristic parameter of the pulse signal model library to obtain a new simulation feature weight matrix;

[0098] In the present invention, the peak intensity detection unit receives the pulse voltage signal of the APD preamplifier unit and is electrically connected to the APD preamplifier unit; the peak intensity detection unit inputs the laser energy peak value of the detected pulse voltage signal into the FPGA control unit, and displays the laser energy peak value on the LCD liquid crystal display screen, so that the test personnel can evaluate the quality of the laser pulse beam of the ranging telescope to be calibrated, thereby eliminating defective products.

[0099] Embodiment 1:

[0100] The power module provides power to the display reminder module and the control module through the power supply unit, and provides bias high voltage of different voltage levels to the calibration module through the high-voltage bias unit to ensure the normal operation of the rangefinder calibration device; the rangefinder telescope to be calibrated is placed on the test station, and the power supply and communication interface are normally connected to the rangefinder calibration device, and the calibration parameters are selected through the LCD display; the calibration parameters include the model to be calibrated, the simulated distance of the rangefinder telescope, the weather mode and the reflectivity of the target object; click on automatic calibration, and the FPGA control unit sends a start calibration command and a simulated distance of the rangefinder telescope to the rangefinder telescope to be calibrated through the communication serial port; after receiving the start calibration command and the simulated distance of the rangefinder telescope, the rangefinder telescope to be calibrated automatically starts the ranging function, and the laser sensor emits a laser pulse beam; the rangefinder calibration device collects and processes the laser pulse beam through the APD preamplifier unit, the voltage comparator and the FPGA controller unit to form a pulse voltage signal;

[0101] After receiving the pulse voltage signal, the FPGA control unit forms a corresponding delay time according to the simulated distance of the ranging telescope, and emits a laser pulse beam. The FPGA control unit adjusts the emission energy of the laser sensor through a variable charging power supply, thereby simulating echo pulse signals of different simulated distances of the ranging telescope and different target reflectivities; after receiving the echo pulse signal, the ranging telescope to be calibrated calculates the actual distance of the ranging telescope, and calibrates the simulated distance of the ranging telescope according to the actual distance of the ranging telescope and the simulated distance of the ranging telescope; after the calibration is successful, the ranging telescope to be calibrated sends a calibration success signal to the FPGA control unit, and the LCD screen displays the calibration success, and the buzzer sounds for prompting; after the simulation distance of the first ranging telescope is calibrated successfully, the FPGA control unit sends a command to start calibrating the simulation distance of the second ranging telescope to the ranging telescope to be calibrated through the communication serial port, until the simulation distances of all ranging telescopes are calibrated;

[0102] The laser sensor emits a laser point light source of different energies; the laser point light source is then converted into parallel light through an optical component and emitted to the range-finding telescope to be calibrated through a first laser attenuation plate; the control module dynamically adjusts the calibration module through an FPGA control unit using a pulse signal model library: the calibration module controls the laser point light source emitted by the laser through a variable charging power supply of a power module and an LD driving unit, and the laser pulse beam emitted by the calibration rangefinder is collected and processed through an APD preamplifier unit: the range-finding telescope to be calibrated emits a laser pulse beam, which is energy-attenuated through a second laser attenuation plate and focused to the APD preamplifier unit through an optical component; the APD preamplifier unit absorbs photons in the attenuated laser pulse beam to generate electron-hole pairs; under a high-voltage electric field, the electron-hole pairs are multiplied through an avalanche effect to generate a current pulse signal; the APD preamplifier unit amplifies the current pulse signal using a signal amplification circuit; the APD preamplifier unit converts the amplified current pulse signal into an analog voltage signal using a signal conversion circuit; the APD preamplifier unit removes noise signals in the analog voltage signal using a filter circuit;

[0103] The voltage comparator of the calibration module receives the analog voltage signal of the APD preamplifier unit, and converts the analog voltage signal into a square wave pulse signal using a square wave generator; the voltage comparator extracts the real-time amplitude V1 of the square wave pulse signal, and compares the real-time amplitude V1 with the voltage threshold V0 set in the threshold adjustment unit: if V1≠V0, the FPGA control unit corrects the environmental impact factor and records the real-time amplitude V1 and the voltage threshold V0; if V1=V0, the FPGA control unit controls the variable charging power supply to adjust the delay time of the laser point light source emitted by the laser, thereby adjusting the simulated distance of the ranging telescope; pulse signal model The feature extraction layer of the library extracts features from the real-time amplitude V1, voltage threshold V0, environmental impact factor, delay time and simulated distance of the ranging telescope to obtain simulated feature values; the learning and training layer of the pulse signal model library performs several iterative training on the simulated feature values ​​to obtain a simulated feature weight matrix; the output update layer and global loss function of the pulse signal model library perform global update optimization on the simulated feature weight matrix to identify and output the delay time corresponding to different simulated distances of the ranging telescope; the FPGA control unit corrects the laser energy of the laser and the simulated distance of the ranging telescope according to the delay time corresponding to different simulated distances of the ranging telescope;

[0104] The voltage comparator converts the analog voltage signal into a square wave pulse signal, and controls the high voltage bias unit through the control module to adjust the APD preamplifier unit; the threshold adjustment unit sets different voltage thresholds for the voltage comparator according to the square wave pulse signal; the display reminder module realizes human-machine operation control through the key unit, and sets and displays the calibration parameters through the LCD display screen, and also uses the buzzer to give real-time prompts on the operating status of the calibration device (calibration start, calibration success and calibration failure) to complete the calibration of the multi-functional telescope rangefinder.

[0105] Embodiment 2:

[0106] The power module provides power to the display reminder module and the control module through the power supply unit, and provides bias high voltage of different voltage levels to the calibration module through the high-voltage bias unit to ensure the normal operation of the rangefinder calibration device; the rangefinder telescope to be calibrated is placed on the test station, and the power supply and communication interface are normally connected to the rangefinder calibration device, and the calibration parameters are selected through the LCD display; the calibration parameters include the model to be calibrated, the simulated distance of the rangefinder telescope, the weather mode and the reflectivity of the target object; click on automatic calibration, and the FPGA control unit sends a start calibration command and a simulated distance of the rangefinder telescope to the rangefinder telescope to be calibrated through the communication serial port; after receiving the start calibration command and the simulated distance of the rangefinder telescope, the rangefinder telescope to be calibrated automatically starts the ranging function, and the laser sensor emits a laser pulse beam; the rangefinder calibration device collects and processes the laser pulse beam through the APD preamplifier unit, the voltage comparator and the FPGA controller unit to form a pulse voltage signal;

[0107] After receiving the pulse voltage signal, the FPGA control unit forms a corresponding delay time according to the simulated distance of the ranging telescope, and emits a laser pulse beam. The FPGA control unit adjusts the emission energy of the laser sensor through a variable charging power supply, thereby simulating echo pulse signals of different simulated distances of the ranging telescope and different target reflectivities; after receiving the echo pulse signal, the ranging telescope to be calibrated calculates the actual distance of the ranging telescope, and calibrates the simulated distance of the ranging telescope according to the actual distance of the ranging telescope and the simulated distance of the ranging telescope; after the calibration is successful, the ranging telescope to be calibrated sends a calibration success signal to the FPGA control unit, and the LCD screen displays the calibration success, and the buzzer sounds for prompting; after the simulation distance of the first ranging telescope is calibrated successfully, the FPGA control unit sends a command to start calibrating the simulation distance of the second ranging telescope to the ranging telescope to be calibrated through the communication serial port, until the simulation distances of all ranging telescopes are calibrated;

[0108] The range-finding telescope to be calibrated emits a laser pulse beam, which passes through a second laser attenuation plate for energy attenuation and is focused to an APD preamplifier unit through an optical component; the APD preamplifier unit absorbs photons in the attenuated laser pulse beam to generate electron-hole pairs; under a high-voltage electric field, the electron-hole pairs are multiplied by an avalanche effect to generate a current pulse signal; the APD preamplifier unit amplifies the current pulse signal using a signal amplification circuit; the APD preamplifier unit converts the amplified current pulse signal into an analog voltage signal using a signal conversion circuit; the APD preamplifier unit removes the noise signal in the analog voltage signal using a filtering circuit; and uses a peak intensity detection unit to detect the relative energy of the analog voltage signal to obtain a laser energy peak value; at the same time, the laser energy peak value is used as a characteristic parameter of a pulse signal model library to obtain a new analog feature weight matrix; the peak intensity detection unit inputs the laser energy peak value of the detected analog voltage signal into an FPGA control unit;

[0109] The voltage comparator of the calibration module receives the analog voltage signal of the APD preamplifier unit, and converts the analog voltage signal into a square wave pulse signal using a square wave generator; the voltage comparator extracts the real-time amplitude V1 of the square wave pulse signal, and compares the real-time amplitude V1 with the voltage threshold V0 set in the threshold adjustment unit: if V1≠V0, the FPGA control unit corrects the environmental impact factor and records the real-time amplitude V1 and the voltage threshold V0; if V1=V0, the FPGA control unit controls the variable charging power supply to adjust the delay time of the laser point light source emitted by the laser, thereby adjusting the simulated distance of the ranging telescope; the characteristics of the pulse signal model library The extraction layer extracts features from the real-time amplitude V1, voltage threshold V0, environmental impact factor, delay time, laser energy peak value and the simulated distance of the ranging telescope to obtain simulated feature values; the learning and training layer of the pulse signal model library performs several iterative training on the simulated feature values ​​to obtain the simulated feature weight matrix; the output update layer and the global loss function of the pulse signal model library perform global update optimization on the simulated feature weight matrix to identify and output the delay time corresponding to different simulated distances of the ranging telescope; the FPGA control unit corrects the laser energy of the laser and the simulated distance of the ranging telescope according to the delay time corresponding to different simulated distances of the ranging telescope;

[0110] The voltage comparator converts the analog voltage signal into a square wave pulse signal, and controls the high voltage bias unit through the control module to adjust the APD preamplifier unit; the threshold adjustment unit sets different voltage thresholds for the voltage comparator according to the square wave pulse signal; the display reminder module realizes human-machine operation control through the key unit, and sets and displays the calibration parameters through the LCD display screen, and also uses the buzzer to give real-time prompts on the operating status of the calibration device (calibration start, calibration success and calibration failure) to complete the calibration of the multi-functional telescope rangefinder.

Claims

1. A multifunctional telescope rangefinder calibration device based on FPGA, characterized in that: It includes a power module, a display reminder module, a control module and a calibration module; wherein, The power module includes a power supply unit and a high voltage bias unit; The power module provides power to the display reminder module and the control module through the power supply unit, and provides bias high voltages of different voltage levels to the calibration module through the high voltage bias unit to ensure the normal operation of the rangefinder calibration device; The display reminder module includes a key unit, a buzzer and an LCD display screen; The display reminder module realizes human-machine operation control through the key unit, sets and displays calibration parameters through the LCD display screen, and uses the buzzer to correct the laser energy of the laser and the simulated distance of the ranging telescope to the FPGA control unit, thereby completing the real-time prompt of the operating status of the multi-functional telescope rangefinder; The control module includes an FPGA control unit; the control module dynamically adjusts the calibration module by using a pulse signal model library through the FPGA control unit to complete the calibration of the multifunctional telescope rangefinder; The calibration module includes an APD preamplifier unit, a voltage comparator, a threshold adjustment unit, a variable charging power supply, an LD drive unit, a laser sensor, an optical component and a laser attenuation sheet; The calibration module controls the laser point light source emitted by the laser sensor through a variable charging power supply and an LD driving unit, and converts the laser point light source into parallel light through an optical component, and transmits it to the range-finding telescope to be calibrated through a first laser attenuation plate. The laser pulse beam emitted by the range-finding telescope to be calibrated is transmitted to the optical component through a second laser attenuation plate, and is collected and processed by an APD preamplifier unit, and then converted into a pulse voltage signal and sent to a voltage comparator; the voltage comparator converts the pulse voltage signal into a square wave pulse signal, and sends it to the control module for collecting and processing the square wave pulse signal; the control module also provides bias high voltages of different voltage levels for the APD preamplifier unit by controlling the high voltage bias unit; the control module also sets different voltage thresholds for the voltage comparator according to the square wave pulse signal through a threshold adjustment unit; The control module is respectively connected to the calibration module and the display reminder module through a communication serial port or a signal line; the power supply module is respectively connected to the display reminder module, the calibration module and the control module through an electrical line.

2. The multifunctional telescope rangefinder calibration device based on FPGA according to claim 1, characterized in that: The operating states include starting calibration, successful calibration and failed calibration; a variable charging power supply for infinitely controlling the laser point light source emitted by the laser sensor to simulate the intensity of the laser point light source reflected by targets with different reflectivity or in different weather conditions; an LD driving unit for controlling the laser sensor; a laser sensor for emitting a laser point light source; an optical component for converting the laser point light source emitted by the laser sensor into laser parallel light; a laser attenuation plate for attenuating the processed laser parallel light; an FPGA control unit for driving the laser sensor to output a laser point light source with an arbitrary delay time, thereby simulating the laser flight time at different distances; an APD preamplifier unit for collecting and processing the laser pulse beam emitted by the ranging telescope to be calibrated; The high voltage bias unit is used to provide bias high voltages of different voltage levels for the APD preamplifier unit; the voltage comparator is used to convert the collected laser pulse beam into a square wave pulse signal; the threshold adjustment unit is used to set different voltage thresholds for the voltage comparator.

3. The multifunctional telescope rangefinder calibration device based on FPGA according to claim 1, characterized in that: The steps of collecting and processing the laser pulse beam emitted by the range-finding telescope to be calibrated by the APD preamplifier unit are as follows: S1: The range-finding telescope to be calibrated emits a laser pulse beam, which is attenuated by the second laser attenuation plate and focused to the APD preamplifier unit through the optical component; S2: The APD preamplifier unit absorbs photons in the attenuated laser pulse beam to generate electron-hole pairs; S3: Under high voltage electric field, electron-hole pairs multiply through avalanche effect, generating current pulse signals; S4: The APD preamplifier unit amplifies the current pulse signal using a signal amplification circuit; S5: The APD preamplifier unit converts the amplified current pulse signal into a pulse voltage signal using a signal conversion circuit; S6: The APD preamplifier unit uses a filter circuit to remove the noise signal in the pulse voltage signal.

4. The multifunctional telescope rangefinder calibration device based on FPGA according to claim 1, characterized in that: The steps of dynamically adjusting the calibration module by the FPGA control unit using the pulse signal model library are as follows: A: The voltage comparator of the calibration module receives the pulse voltage signal of the APD preamplifier unit and converts the pulse voltage signal into a square wave pulse signal using a square wave generator; B: The voltage comparator extracts the real-time amplitude of the square wave pulse signal , and the real-time amplitude The voltage threshold set in the threshold adjustment unit Make comparisons; C: If , the FPGA control unit corrects the environmental impact factor and records the real-time amplitude and voltage threshold ;like , the FPGA control unit controls the variable charging power supply to adjust the delay time of the laser point light source emitted by the laser, and then adjusts the simulated distance of the ranging telescope; D: The feature extraction layer of the pulse signal model library is used to extract the real-time amplitude , voltage threshold , environmental influencing factors, delay time and simulated distance of the ranging telescope are used for feature extraction to obtain simulated feature values; E: The learning and training layer of the pulse signal model library performs several iterative training on the simulated eigenvalues ​​to obtain the simulated feature weight matrix; F: The output update layer and global loss function of the pulse signal model library perform global update optimization on the simulated feature weight matrix to identify and output the delay time corresponding to the simulated distances of different ranging telescopes; G: The FPGA control unit corrects the laser energy of the laser and the simulated distance of the ranging telescope according to the delay time corresponding to different simulated distances of the ranging telescope, thereby completing the calibration of the multi-functional telescope rangefinder.

5. The multifunctional telescope rangefinder calibration device based on FPGA according to claim 4, characterized in that: The feature extraction layer includes two Convolutional layer, 3 Convolutional layer, 2 by Convolutional layers and The convolutional layer consists of a convolutional block and two Average pooling layer; the learning training layer consists of 2 series Convolutional layer, 2 Adaptive pooling layer, 1 Block, 1 Block, 1 Convolutional layer and 1 ReLU activation function; the output update layer includes 3 Convolutional layer, 2 Convolutional layers, 2 dropout layers, and 2 fully connected layers.

6. The multifunctional telescope rangefinder calibration device based on FPGA according to claim 4, characterized in that: The FPGA control unit corrects the laser energy of the laser and the simulated distance of the ranging telescope, and then completes the calibration steps of the multifunctional telescope rangefinder as follows: G1: Place the rangefinder telescope to be calibrated on the test station, connect the power supply and communication interface to the rangefinder calibration device normally, and select the calibration parameters through the LCD display; the calibration parameters include the model to be calibrated, the simulated distance of the rangefinder telescope, the weather mode and the reflectivity of the target object; G2: Click on automatic calibration, and the FPGA control unit sends a calibration start command and the simulated distance of the telescope to be calibrated through the communication serial port; G3: After receiving the calibration start command and the simulated distance of the ranging telescope, the ranging function is automatically started, and the laser sensor emits a laser pulse beam; G4: The rangefinder calibration device collects and processes the laser pulse beam through the APD preamplifier unit, voltage comparator and FPGA controller unit to form a pulse voltage signal; G5: After receiving the pulse voltage signal, the FPGA control unit forms a corresponding delay time according to the simulated distance of the ranging telescope and emits a laser pulse beam. The FPGA control unit adjusts the emission energy of the laser sensor through a variable charging power supply to simulate the echo pulse signals of different ranging telescope simulated distances and different target reflectivity; G6: After receiving the echo pulse signal, the rangefinder telescope to be calibrated calculates the actual distance of the rangefinder telescope, and calibrates the simulated distance of the rangefinder telescope according to the actual distance of the rangefinder telescope and the simulated distance of the rangefinder telescope. After the calibration is successful, the rangefinder telescope to be calibrated sends a calibration success signal to the FPGA control unit, and the LCD screen displays the calibration success, and the buzzer sounds to prompt; G7: After the first ranging telescope simulated distance is calibrated successfully, the FPGA control unit sends a command to start calibrating the second ranging telescope simulated distance to the ranging telescope to be calibrated through the communication serial port, and then calibrates the simulated distances of all ranging telescopes in sequence according to steps G3 to G7.

7. The multifunctional telescope rangefinder calibration device based on FPGA according to claim 1, characterized in that: The calibration module further includes a peak intensity detection unit; the peak intensity detection unit is used to detect the relative energy of the laser emitted by the ranging telescope to be calibrated, so as to obtain the peak energy of the laser emitted by the ranging telescope to be calibrated; The laser energy peak is used as the characteristic parameter of the pulse signal model library to obtain a new simulation feature weight matrix.

8. The FPGA-based multifunctional telescope rangefinder calibration device according to claim 7, characterized in that: The peak intensity detection unit receives the pulse voltage signal of the APD preamplifier unit and is electrically connected to the APD preamplifier unit; the peak intensity detection unit inputs the laser energy peak value of the detected pulse voltage signal into the FPGA control unit, and displays the laser energy peak value on the LCD liquid crystal display screen, so that the test personnel can evaluate the quality of the laser pulse beam of the ranging telescope to be calibrated, thereby eliminating defective products.

Images