A ground penetrating radar transmit voltage dynamic adjustment system

Abstract

The application provides a ground penetrating radar transmitting voltage dynamic adjustment system, which adopts a split type setting transmitting antenna subsystem and a receiving antenna subsystem; the receiving antenna subsystem adjusts a digital potentiometer to reduce the level of a high voltage power supply in the case that an analog-to-digital converter range is full and / or a direct wave is saturated according to the state of the received signal, and adjusts the digital potentiometer to increase the level of the high voltage power supply in the case that the analog-to-digital converter range is not full and / or the direct wave is not saturated, so that the ground penetrating radar can better adapt to different geological conditions, the signal noise ratio is improved, the detection resolution is improved, the ground penetrating radar can quickly respond to different detection tasks, and hardware does not need to be replaced or complicated setting is needed.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of radar equipment, and in particular to a ground penetrating radar transmitting voltage dynamic adjustment system. BACKGROUND

[0002] Ground penetrating radar (GPR) is a geophysical method that uses high-frequency electromagnetic waves to detect underground structures. With the acceleration of urbanization, the demand for underground space exploration is growing, and GPR is widely used in archaeology, mineral exploration, disaster geological survey, geotechnical engineering investigation, engineering quality detection and other fields due to its high precision, high efficiency and non-destructive characteristics.

[0003] The dynamic adjustment of the transmitting voltage has a significant impact on the performance of the ground penetrating radar. The transmitting voltage is proportional to the energy of the radar signal, and the GPR signal at a certain distance is proportional to the peak voltage. Increasing the transmitting voltage can improve the penetration of the radar signal and thus increase the detection depth. However, the transmitting voltage also needs to be matched with the system, and the geological conditions need to be considered. Different geological media have different absorption and scattering degrees of electromagnetic waves. In some high-conductivity geological conditions, the signal attenuation is large, and even if the transmitting voltage is increased, the expected detection depth may not be achieved. At the same time, increasing the transmitting voltage may result in more noise in the received signal, which increases the complexity of data processing and may affect the interpretation and accuracy of the final data. Therefore, there is an urgent need for a ground penetrating radar system that can dynamically adjust the transmitting voltage. SUMMARY

[0004] In view of this, the embodiments of the present application provide a ground penetrating radar transmitting voltage dynamic adjustment system to eliminate or improve one or more defects in the prior art, and solve the problem that the prior art cannot adaptively adjust the transmitting voltage according to the ground penetrating radar signal state, resulting in low detection accuracy.

[0005] One aspect of the present application provides a ground penetrating radar transmitting voltage dynamic adjustment system, which comprises a transmitting antenna subsystem and a receiving antenna subsystem arranged in a split manner.

[0006] The transmitting antenna subsystem comprises:

[0007] a high-voltage module for providing a high-voltage power supply;

[0008] a pulse source module for outputting a high-voltage pulse signal based on the high-voltage power supply and a trigger pulse;

[0009] a transmitting antenna for converting the high-voltage pulse signal into a first electromagnetic wave and radiating outwardly;

[0010] The receiving antenna subsystem comprises:

[0011] a receiving antenna for receiving an external second electromagnetic wave, the second electromagnetic wave including a direct wave and a reflected wave returned in a medium;

[0012] a master control and data acquisition module for performing noise suppression, gain adjustment, imaging, and image optimization processing on the reflected wave, and regulating the high-voltage power supply output by the high-voltage module through an analog-to-digital converter detecting the state of the direct wave; wherein the master control and data acquisition module controls a digital potentiometer through an FPGA chip to configure a control resistor for the high-voltage module to adjust the high-voltage power supply; the FPGA chip adjusts the digital potentiometer to reduce the level of the high-voltage power supply in the case of full range of the analog-to-digital converter and / or saturation of the direct wave, and adjusts the digital potentiometer to increase the level of the high-voltage power supply in the case of not full range of the analog-to-digital converter and / or not saturation of the direct wave.

[0013] In some embodiments, the pulse source module is composed of multiple stages of avalanche diodes, each avalanche diode is connected in series, and a parallel resistor and a capacitor are provided at both ends of each avalanche diode for equalization and overcurrent limiting.

[0014] In some embodiments, the high-voltage module adopts a reference voltage division adjustment structure, and an external first resistor and a second resistor are set by the digital potentiometer to divide the fixed reference voltage of the high-voltage module to adjust the voltage of the high-voltage power supply, the expression is:

[0015] ;

[0016] wherein, represents the fixed reference voltage, represents the first resistor, represents the second resistor.

[0017] In some embodiments, the high-voltage module adopts a feedback voltage division adjustment structure, and the first resistor and the second resistor are set by the digital potentiometer to form a feedback voltage division network, and the voltage of the high-voltage power supply is adjusted according to the multiple of the reference voltage of the high-voltage module based on the resistance division ratio of the feedback voltage division network, the expression is:

[0018] ;

[0019] wherein, represents the reference voltage, represents the first resistor, represents the second resistor.

[0020] In some embodiments, the system further comprises:

[0021] a distance adjusting mechanism for adjusting the distance between the transmitting antenna and the receiving antenna;

[0022] a user interaction module for controlling the distance adjusting mechanism to adjust the distance between the transmitting antenna and the receiving antenna based on a user inputted adjusting instruction.

[0023] In some embodiments, the distance adjusting mechanism comprises:

[0024] a slide rail;

[0025] a first fixed base fixedly arranged on the slide rail for fixing the transmitting antenna;

[0026] a second fixed base slidably arranged on the slide rail for fixing the receiving antenna;

[0027] a driving motor arranged on the second fixed base for driving the second fixed base to slide on the slide rail.

[0028] In some embodiments, the FPGA chip adjusts the level of the high-voltage power supply based on a proportional-integral-derivative feedback control algorithm, comprising:

[0029] calculating an error by comparing a current level value of the direct wave or the reflected wave with a target value , the calculation formula being:

[0030] ;

[0031] wherein, the target value is represented by Pd, the current level value is represented by P;

[0032] then the adjustment amount of the high-voltage power supply is :

[0033] ;

[0034] wherein, Kp is a proportional coefficient, Ki is an integral coefficient, Kd is a differential coefficient.

[0035] In some embodiments, the FPGA chip adjusts the level of the high-voltage power supply based on a policy network pre-trained by a reinforcement learning model, taking the level of the high-voltage power supply, the level of the direct wave, the dynamic range of the reflected wave, and the ratio of the dynamic range to the analog-to-digital converter range as inputs, and outputting an adjustment amount of the level of the high-voltage power supply.

[0036] In some embodiments, the pre-training step of the policy network comprises:

[0037] constructing a state space, the state space comprising a level of the high-voltage power supply, a level of the direct wave, a dynamic range of the reflected wave, a ratio of the dynamic range to a range of the analog-to-digital converter;

[0038] constructing an action space, the action space being an amount of level adjustment of the high-voltage power supply;

[0039] outputting the amount of level adjustment of the high-voltage power supply based on a policy network in reinforcement learning, taking parameters of the state space as input, weighting and summing a direct wave unsaturation reward, a dynamic range utilization rate reward and an adjustment amplitude penalty to construct a reward function, and updating parameters of the policy network by minimizing the reward function in a plurality of iterations until the reward function converges;

[0040] wherein a calculation formula of the reward function R is:

[0041] ;

[0042] wherein, represents the direct wave unsaturation reward, represents the dynamic range utilization rate reward,

[0043] represents the adjustment amplitude penalty; , and are weight coefficients;

[0044] ;

[0045] ;

[0046] ;

[0047] wherein K represents a ratio of the dynamic range of the reflected wave to the range of the analog-to-digital converter, represents the amount of level adjustment of the high-voltage power supply.

[0048] In some embodiments, the policy network is composed of a convolutional neural network and a fully connected network.

[0049] The present application has at least the following beneficial effects:

[0050] The ground penetrating radar transmitting voltage dynamic adjustment system adopts the split type transmission antenna subsystem and the receiving antenna subsystem, the receiving antenna subsystem adjusts the digital potentiometer to reduce the level of the high voltage power supply in the case of full range of the analog-digital converter and / or direct wave saturation according to the state of the received signal, and adjusts the digital potentiometer to increase the level of the high voltage power supply in the case of not full range of the analog-digital converter and / or direct wave not saturated, so that the ground penetrating radar can better adapt to different geological conditions, help to improve the signal-to-noise ratio of the signal, and further improve the detection resolution, can quickly respond to different detection tasks, and does not need to replace hardware or make complex settings.

[0051] Additional advantages, objects, and features of the application will be set forth in part in the description which follows, and in part will become apparent to those skilled in the art upon examination of the following or can be learned by practice of the application. The objects and other advantages of the application can be realized and attained by the structure particularly pointed out in the written description and claims hereof as well as the appended drawings.

[0052] It will be understood by those skilled in the art that the objects and advantages of the present application can be realized and attained by the structure particularly pointed out in the written description and claims hereof as well as the appended drawings. BRIEF DESCRIPTION OF DRAWINGS

[0053] The accompanying drawings, which are included to provide a further understanding of the application and are incorporated in and constitute a part of this application, illustrate embodiments of the application and together with the description serve to explain the principles of the application. In the drawings:

[0054] Figure 1 The structure schematic view of the ground penetrating radar transmitting voltage dynamic adjustment system of an embodiment of the present application.

[0055] Figure 2 The working principle diagram of the pulse source module in the ground penetrating radar transmitting voltage dynamic adjustment system of another embodiment of the present application.

[0056] Figure 3 The first type working principle diagram of the high voltage module in the ground penetrating radar transmitting voltage dynamic adjustment system of another embodiment of the present application.

[0057] Figure 4 The second type working principle diagram of the high voltage module in the ground penetrating radar transmitting voltage dynamic adjustment system of another embodiment of the present application.

[0058] Figure 5 The circuit connection diagram of using the FPGA chip as the control end of the digital potentiometer and the first type high voltage module.

[0059] Figure 6The circuit connection diagram of the FPGA chip as the control end of the digital potentiometer and the second type of high-voltage module.

[0060] Figure 7 The circuit diagram of adding resistance for high-voltage output range constraint. Figure 5 The circuit diagram of adding resistance for high-voltage output range constraint.

[0061] Figure 8 The circuit diagram of adding resistance for high-voltage output range constraint. Figure 6 The circuit diagram of adding resistance for high-voltage output range constraint.

[0062] Figure 9 The working logic schematic diagram of the ground penetrating radar transmitting voltage dynamic adjustment system according to an embodiment of the present application.

[0063] Reference signs:

[0064] 100: transmitting antenna subsystem; 110: high-voltage module; 120: pulse source module;

[0065] 130: transmitting antenna; 200: receiving antenna subsystem; 210: receiving antenna;

[0066] 220: master control and data acquisition module; 221: digital potentiometer; 222: FPGA chip. DETAILED DESCRIPTION

[0067] In order to make the objects, technical solutions and advantages of the present application clearer, the present application will be further described in detail below with reference to the embodiments and the drawings. Herein, the illustrative embodiments of the present application and the descriptions thereof are used to explain the present application, but are not used as the limitation of the present application.

[0068] Herein, it also needs to be explained that, in order to avoid the present application being obscured by unnecessary details, only the structures and / or processing steps closely related to the solutions according to the present application are shown in the drawings, and other details not closely related to the present application are omitted.

[0069] It should be emphasized that the term "comprises / comprising" as used herein is used to indicate the presence of the stated features, elements, steps or components, but does not preclude the presence or addition of one or more other features, elements, steps or components.

[0070] Herein, it also needs to be explained that, if not specially stated, the term "connection" as used herein can not only mean direct connection, but also means indirect connection with the presence of intermediate objects.

[0071] Hereinafter, the embodiments of the present application will be described with reference to the drawings. In the drawings, the same reference signs represent the same or similar parts or the same or similar steps.

[0072] The application provides a ground penetrating radar transmitting voltage dynamic adjustment system, which aims to adjust the transmitting voltage in real time according to different geological conditions, so as to optimize the detection depth and resolution. The function of dynamically adjusting the transmitting voltage is to adjust the transmitting voltage in real time according to different geological conditions and detection targets, so as to optimize the detection depth and resolution. This adjustment capability enables the ground penetrating radar to adapt to various complex underground environments, and improves the accuracy and reliability of detection. Through the dynamic adjustment of the transmitting voltage, the best detection effect can be achieved under different geological conditions, and the detection depth and resolution performance of the radar are optimized to the maximum.

[0073] Specifically, the application provides a ground penetrating radar transmitting voltage dynamic adjustment system, as shown in Figure 1 and Figure 9 , the system comprises a transmitting antenna 130 subsystem 100 and a receiving antenna subsystem 200 arranged in a split mode.

[0074] The transmitting antenna 130 subsystem 100 comprises a high-voltage module 110, a pulse source module 120 and a transmitting antenna 130.

[0075] The high-voltage module 110 is used to provide a high-voltage power supply to provide the required driving voltage for the pulse source module 120. Its core function is to convert and stably adjust the input power supply through a control circuit, so that the output voltage can meet the working requirements of the target device. The high-voltage module 110 can comprise a reference voltage source and an adjustment circuit. The reference voltage source provides a stable maximum voltage value for the output voltage, and the adjustment circuit changes the voltage division ratio by using external resistors or digital control devices (such as a digital potentiometer 221), so as to adjust the output voltage. The external control mode can be divided into resistance division and programmed control; in the resistance division mode, fixed or variable resistors (such as R1 and R2) are used to adjust the output voltage by resistance ratio; in the programmed control mode, a digital potentiometer 221 is connected to a control chip (such as an FPGA), to realize automatic and accurate adjustment. The high-voltage module 110 can also comprise a reference voltage source and an adjustment circuit. The adjustment circuit uses external resistors or digital control devices (such as a digital potentiometer 221), and uses fixed or variable resistors (such as R1 and R2) to output a voltage according to the multiple of the reference voltage through the resistance ratio.

[0076] The pulse source module 120 outputs a high-voltage pulse signal based on a high-voltage power supply and a trigger pulse. In some embodiments, the pulse source module 120 is composed of multiple stages of avalanche diodes, each of which is connected in series in turn, and each avalanche diode is provided with a parallel resistance and a capacitor at both ends, for equalization and overcurrent limiting. The parallel resistance ensures that each diode shares the voltage uniformly, preventing mismatch caused by manufacturing errors. The parallel capacitor improves circuit response speed and stores energy to enhance the avalanche effect. Each stage of avalanche diodes bears part of the reverse breakdown voltage. When the total voltage reaches a critical value, all avalanche diodes enter an avalanche breakdown state at the same time, releasing the energy in the energy storage capacitor, forming a high-speed, high-amplitude voltage pulse.

[0077] The transmitting antenna 130 is used to convert the high-voltage pulse signal into a first electromagnetic wave and radiate it outward. The transmitting antenna 130 can adopt a dipole antenna, a Bow-Tie antenna, a horn antenna, and a Vivaldi antenna, etc. The dipole antenna is simple in structure and composed of two conductors, which is suitable for narrowband applications but limited in wideband detection performance; the Bow-Tie antenna realizes wideband radiation through a metal plate in the shape of a hyperbola, and is particularly suitable for efficient transmission and reception of wideband signals, and is commonly used in ground penetrating radar. The horn antenna focuses and radiates electromagnetic waves through a horn-shaped structure, with strong directivity and high efficiency, but the volume is large, which is suitable for scenes with high requirements for high resolution. The Vivaldi antenna is a kind of tapered slot antenna, which is light in structure and wide in frequency band, and is suitable for radiation and reception of high-frequency signals.

[0078] The receiving antenna subsystem 200 includes a receiving antenna 210 and a master control and data acquisition module 220.

[0079] The receiving antenna 210 is used to accept external second electromagnetic waves, including direct waves and reflected waves returned in the medium. The receiving antenna 210 can adopt a dipole antenna, a Bow-Tie antenna, a horn antenna and a Vivaldi antenna. The direct wave is an electromagnetic wave signal directly transmitted by the transmitting antenna 130 and received by the receiving antenna 210 in the ground penetrating radar (GPR) system. It is a wave that propagates directly from the transmitting antenna 130 to the receiving antenna 210 without reflection or scattering by the underground medium. The direct wave is an important component of radar signal propagation and is usually the first signal received in the system because it has the shortest propagation path. The reflected wave is a signal returned and received by the receiving antenna 210 after the electromagnetic wave emitted by the ground penetrating radar (GPR) system encounters a discontinuous interface of the underground medium (such as the boundary of different materials, underground targets or structures) during propagation due to the difference in dielectric constant or conductivity. The reflected wave carries the characteristic information of the target or medium boundary, and its strength and delay time are closely related to the material, electromagnetic properties and depth of the underground interface. By analyzing the time, amplitude and phase changes of these reflected waves, the radar system can identify the location, shape, size and composition of underground objects. The reflected wave is the key signal for ground penetrating radar to achieve underground target detection and imaging, but in complex media, it may be affected by noise, multiple reflections and scattering, and needs to be interpreted after noise suppression and filtering processing.

[0080] The main control and data acquisition module 220 is used for noise suppression, gain adjustment, imaging and image optimization processing of the reflected wave. Noise suppression removes environmental noise and unwanted signals through filtering techniques such as low-pass filtering, high-pass filtering or band-pass filtering, and reduces random noise using multiple stack averaging methods. Gain adjustment compensates for signal attenuation caused by increasing propagation distance through dynamic gain control (DGC), enhances deep reflected wave signals, and balances overall signal amplitude. Imaging converts the processed time domain signal into a spatial distribution map (such as a two-dimensional or three-dimensional profile), often using radar beam focusing algorithms or reverse time migration algorithms to improve spatial resolution. Finally, image optimization processing uses deconvolution, interpolation and pseudo-color enhancement techniques to improve image clarity and interpretability, further highlighting target features and suppressing background interference. The comprehensive application of these steps enables ground penetrating radar to generate accurate underground target images and provide high-quality data support for geological, archaeological and engineering exploration.

[0081] The main control and data acquisition module 220 regulates the high-voltage power supply output by the high-voltage module 110 by detecting the state of the direct wave through an analog-to-digital converter; wherein the main control and data acquisition module 220 controls the digital potentiometer 221 through the FPGA chip 222 to configure the control resistance for the high-voltage module 110 to adjust the high-voltage power supply; the FPGA chip 222 adjusts the digital potentiometer 221 to reduce the level of the high-voltage power supply in the case of analog-to-digital converter range full and / or direct wave saturation, and adjusts the digital potentiometer 221 to increase the level of the high-voltage power supply in the case of analog-to-digital converter not range full and / or direct wave not saturated.

[0082] The FPGA chip 222 (Field-Programmable Gate Array) is a high-performance programmable logic device composed of a large number of configurable logic units, memory units and programmable interconnection matrix, which can be programmed according to application requirements through hardware description language (HDL). The core feature of FPGA is that its hardware logic can be reconfigured multiple times, which can realize various functions from simple logic operation to complex digital signal processing. Compared with ASIC (Application Specific Integrated Circuit), FPGA has the advantages of high flexibility and short development cycle. The digital potentiometer 221 is an electronic device based on resistance voltage division principle, its working principle is to change the voltage division point of resistance network through digital control, thereby adjusting the output voltage or current. It is usually composed of a precise segmented resistance chain and electronic switches inside, each resistance segment is connected by switches, and the state of the switch is controlled by digital signals. When an input digital value (usually provided by a microcontroller or FPGA) is input, the switch selects the corresponding resistance segment to adjust the output resistance or voltage division ratio. The digital potentiometer 221 can simulate the function of traditional mechanical potentiometers, but has the advantages of small size, high precision, programmability and strong durability, and is widely used in gain adjustment, power voltage regulation and filter parameter configuration applications.

[0083] An analog-to-digital converter (ADC) converts analog signals into digital signals and encodes them according to the strength of their input signals. The range of an ADC refers to the range of input voltage that it can effectively measure. If the input signal strength exceeds the maximum measurement range of the ADC (i.e. exceeds its maximum input voltage), it will cause the range to be full, also known as "saturation". At this time, the ADC cannot accurately represent the input signal, resulting in signal distortion or loss of details. If the output digital value of the analog-to-digital converter reaches its maximum value (for example, the maximum value of an 8-bit ADC is 255), it can be considered that the ADC has reached the range full. This means that the input signal has exceeded the measurement range of the ADC.

[0084] Direct wave saturation refers to the intensity of the direct wave signal received by the receiving antenna 210 being too high, exceeding the dynamic range of the receiving system, resulting in signal saturation. When the signal is saturated, the receiving system cannot accurately measure the intensity of the signal with high intensity, which will affect the reception and analysis of the subsequent reflected wave signal. The intensity of the direct wave can be judged by the amplitude of the received signal. If the amplitude of the received direct wave signal is close to or equal to the maximum receiving capacity of the receiving system (i.e. the saturation level of the receiver), it means that the direct wave signal has been saturated. At this time, the receiving system may not be able to accurately distinguish between the direct wave and the reflected wave, resulting in system distortion.

[0085] In some embodiments, the high-voltage module 110 adopts a reference voltage division adjustment structure, and sets the external first resistance and the second resistance through the digital potentiometer 221 to divide the fixed reference voltage of the high-voltage module 110 to adjust the voltage of the high-voltage power supply, and the expression is:

[0086] ;

[0087] wherein, represents the fixed reference voltage, represents the first resistance, represents the second resistance.

[0088] In some embodiments, the high-voltage module 110 adopts a feedback voltage division adjustment structure, and sets the external first resistance and the second resistance through the digital potentiometer 221 to form a feedback voltage division network, and adjusts the voltage of the high-voltage power supply according to the multiple of the reference voltage of the high-voltage module 110 based on the resistance division ratio of the feedback voltage division network, and the expression is:

[0089] ;

[0090] wherein, represents the reference voltage, represents the first resistance, represents the second resistance.

[0091] In some embodiments, the system further comprises a distance adjustment mechanism and a user interaction module.

[0092] The distance adjusting mechanism is used to adjust the distance between the transmitting antenna 130 and the receiving antenna 210. The adjustment of the distance can affect the propagation characteristics of the radar wave and the reception quality of the signal. A smaller antenna distance helps to improve the spatial resolution of the system, which is suitable for high-precision detection at close range, but can cause the direct wave signal to be too strong, which can easily cause signal saturation or interference. A larger antenna distance is conducive to receiving deeper reflected waves, improving detection depth and anti-interference capability, but can cause signal attenuation and resolution reduction. Therefore, adjusting the antenna distance can balance the detection depth and resolution, avoid excessive saturation of the direct wave, and optimize the signal quality and detection accuracy of the system according to different detection requirements.

[0093] The user interaction module is used to control the distance adjusting mechanism to adjust the distance between the transmitting antenna 130 and the receiving antenna 210 based on the user input adjustment instruction. The user interaction module can use a touch screen module with display function to collect data and interact through a corresponding UI interface.

[0094] In some embodiments, the distance adjusting mechanism includes a slide rail, a first fixed base, a second fixed base, and a drive motor.

[0095] The slide rail can be deployed according to the carrier structure, for example, for a handheld ground penetrating radar, the slide rail can be arranged at the front end of the handheld handle, arranged transversely. For a self-moving trolley, it can be arranged at the bottom of the trolley platform.

[0096] The first fixed base is fixedly arranged on the slide rail for fixing the transmitting antenna 130.

[0097] The second fixed base is slidably arranged on the slide rail for fixing the receiving antenna 210.

[0098] The drive motor is arranged on the second fixed base for driving the second fixed base to slide on the slide rail. The transmission mode can use gear or belt transmission.

[0099] In some embodiments, the FPGA chip 222 adjusts the level of the high-voltage power supply based on a proportional-integral-derivative feedback control algorithm, including:

[0100] Comparing the current level value of the direct wave or reflected wave with the target value, the error is calculated , the calculation formula is:

[0101] ;

[0102] Wherein, represents the target value, represents the current level value;

[0103] The adjustment amount of the high-voltage power supply is:

[0104] ;

[0105] wherein, is a proportional coefficient, is an integral coefficient, is a differential coefficient.

[0106] In some embodiments, the FPGA chip 222 outputs the level adjustment amount of the high-voltage power supply based on the pre-trained policy network of the reinforcement learning model with the level of the high-voltage power supply, the level of the direct wave, the dynamic range of the reflected wave, and the ratio of the dynamic range to the analog-to-digital converter range as inputs.

[0107] In some embodiments, the pre-training step of the policy network includes steps S101-S103:

[0108] Step S101: constructing a state space, the state space including the level of the high-voltage power supply, the level of the direct wave, the dynamic range of the reflected wave, and the ratio of the dynamic range to the analog-to-digital converter range.

[0109] Step S102: constructing an action space, the action space being the level adjustment amount of the high-voltage power supply.

[0110] Step S103: based on the policy network in reinforcement learning, inputting the parameters of the state space and outputting the level adjustment amount of the high-voltage power supply, weighting and summing the direct wave unsaturation reward, the dynamic range utilization rate reward, and the adjustment amplitude penalty to construct a reward function, and updating the parameters of the policy network by minimizing the reward function in multiple iterations until the reward function converges.

[0111] wherein, the calculation formula of the reward function R is:

[0112] ;

[0113] wherein, represents the direct wave unsaturation reward, represents the dynamic range utilization rate reward,

[0114] represents the adjustment amplitude penalty; 、 and are weight coefficients;

[0115] ;

[0116] ;

[0117] ;

[0118] K represents the ratio of the dynamic range of the reflected wave to the range of the analog-to-digital converter, represents the level adjustment amount of the high-voltage power supply.

[0119] In some embodiments, the policy network is constituted by a convolutional neural network and a fully connected network.

[0120] The application will be described below in conjunction with a specific embodiment:

[0121] The embodiment provides a transmitting voltage dynamic adjustment system applied to a ground penetrating radar, aiming to adjust the transmitting voltage in real time according to different geological conditions, so as to optimize the detection depth and resolution. The system is a split type ground penetrating radar system, which comprises a transmitting antenna system and a receiving antenna system. The transmitting antenna system comprises a transmitting antenna, a pulse source and a high-voltage module, and the receiving antenna system comprises a receiving antenna, a master control and data acquisition module. The transmitting voltage adjustment module is integrated in the master control circuit, and the transmitting voltage is dynamically adjusted according to the input of the geological parameter detection unit.

[0122] The ground penetrating radar is used for emitting a transient high-voltage pulse signal to a detection surface by using an antenna, and receiving a return wave of a target object by using a receiving antenna, so as to judge the physical information of the target object. Therefore, the transmitting power of the pulse source has a huge influence on the performance of the ground penetrating radar. The pulse source is composed of multiple avalanche diodes, an input trigger pulse and a high-voltage power supply, and outputs a high-voltage pulse signal. The working principle is as follows Figure 2 .

[0123] As can be known from the working principle of the pulse source, the transmitting power of the pulse source is determined by the level of the high-voltage power supply. Therefore, the transmitting power of the pulse source of the ground penetrating radar is realized by adjusting the voltage value of the high-voltage power supply.

[0124] The high-voltage module with the output voltage adjustment function can realize the adjustment of the output power supply through the configuration of the peripheral resistance, and generally has the following two modes.

[0125] The first mode is as shown in Figure 3 , the high-voltage module itself outputs a reference voltage, and the output voltage is adjusted by adjusting the resistance values of R1 and R2, and the adjustment range is between 0 and Vmax.

[0126] ;

[0127] wherein, represents a fixed reference voltage, represents a first resistance, represents a second resistance.

[0128] The second mode is as shown in Figure 4 , the high-voltage module internally generates a reference voltage, and the value of the output power supply is adjusted through the proportional relationship of the external resistance.

[0129] ;

[0130] wherein, represents a reference voltage, represents a first resistance, represents a second resistance.

[0131] The transmitting voltage adjusting circuit design is achieved by using a digital potentiometer. The resistance value can be adjusted under program control by using the digital potentiometer. The FPGA chip is used as the control end of the digital potentiometer to control the resistance value of the potentiometer. Thus, the purpose of controlling the output voltage of the high-voltage module is achieved, thereby controlling the transmitting power of the pulse source. The connection structure diagram is shown in Figure 5 and 6 .

[0132] The resistance value of the digital potentiometer is not continuously adjustable, but there are 32 gears, 64 gears, and 128 gears to choose from. When selecting, pay attention to the resistance value of the digital potentiometer.

[0133] In actual application, resistors can be configured in the circuit to achieve the purpose of restricting the output range of the high-voltage module. As shown in Figure 7 .

[0134] The function of the resistor R2 is to limit the lower limit of the output of the high-voltage module, and the function of the resistor R1 is to limit the upper limit of the output of the high-voltage module. By reasonably selecting the resistance values of R1, R2, and the digital potentiometer, the output range of the high-voltage module can be limited, and the safety of the circuit operation can be effectively controlled.

[0135] As shown in Figure 8 , the function of the resistor R1 is to limit the lower limit of the output of the high-voltage module. By reasonably selecting the resistance values of R1, R2, and the digital potentiometer, the output range of the high-voltage module can be limited, and the safety of the circuit operation can be effectively controlled.

[0136] The transmitting voltage is controlled by the host computer software to achieve adaptive adjustment of the transmitting voltage. The software collects ground penetrating radar echo data and analyzes the direct wave amplitude in the ground penetrating radar data to automatically adjust the transmitting voltage to optimize the detection effect. In the case where the analog-to-digital converter range is full and / or the direct wave is saturated, the digital potentiometer is adjusted to reduce the level of the high-voltage power supply. In the case where the analog-to-digital converter is not full range and / or the direct wave is not saturated, the digital potentiometer is adjusted to increase the level of the high-voltage power supply. Through real-time feedback and voltage adjustment, the system can quickly respond to changes in underground conditions and provide more accurate detection results. The adaptive adjustment algorithm is shown in Figure 9 , until the direct wave amplitude reaches the full quantization level.

[0137] Therefore, the embodiment adjusts the voltage, which can improve the detection depth and resolution. By dynamically adjusting the transmission voltage, the ground penetrating radar can better adapt to different geological conditions. The increase of the transmission voltage can provide greater penetration, thereby increasing the detection depth, which is particularly important for the detection of deep geological structures. At the same time, fine adjustment of the transmission voltage also helps to improve the signal-to-noise ratio of the signal, thereby improving the detection resolution. This resolution improvement is crucial for identifying shallow details and complex structures, especially in the application of archaeology, geology and environmental science. The adaptability of the system can be enhanced, and the dynamic adjustment of the transmission voltage enables the ground penetrating radar system to adapt to various complex underground environments. In strata with high water content, electromagnetic waves attenuate faster, and by increasing the transmission voltage, the attenuation can be compensated for to maintain the strength of the signal, thereby improving the accuracy and reliability of the detection. The operation is simple, the user-friendly interface and intuitive operation design enable the operator to easily adjust the transmission voltage according to the detection requirements. Dynamic adjustment of the transmission voltage can provide a wider range of data, which is very helpful for subsequent data processing and interpretation. By adjusting different transmission voltages, data of different depths and resolutions can be obtained, which is crucial for optimizing data processing algorithms and improving imaging quality. It can improve work efficiency, and by dynamically adjusting the transmission voltage, the ground penetrating radar system can quickly respond to different detection tasks without the need to replace hardware or make complex settings. This rapid response capability greatly improves work efficiency, especially in situations requiring quick decision-making, such as search and rescue operations and engineering quality detection.

[0138] In summary, the ground penetrating radar transmission voltage dynamic adjustment system of the present application adopts a split type transmission antenna subsystem and a receiving antenna subsystem. The receiving antenna subsystem adjusts the digital potentiometer to reduce the level of the high-voltage power supply in the case of full range of analog-to-digital converter and / or direct wave saturation, and to increase the level of the high-voltage power supply in the case of non-full range of analog-to-digital converter and / or non-saturation of direct wave, according to the state of the received signal, so that the ground penetrating radar can better adapt to different geological conditions, which helps to improve the signal-to-noise ratio of the signal, thereby improving the detection resolution, and can quickly respond to different detection tasks without the need to replace hardware or make complex settings.

[0139] Those of ordinary skill in the art will appreciate that the various illustrative components, systems and methods described in connection with the embodiments disclosed herein can be implemented as hardware, software, or both. The particular implementation is dependent on the specific application and design constraints imposed on the overall system. Skilled persons can implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present application. When implemented in hardware, for example, the hardware can comprise an electronic circuit, an Application Specific Integrated Circuit (ASIC), a suitable firmware, a plug-in, a functional card, etc. When implemented in software, the elements of the application are the program or code segments to perform a specific task. The program or code segments can be stored in a machine-readable medium, or transmitted by a carrier wave as data signals over a transmission medium or communication link.

[0140] It is to be understood that the application is not limited to the particular configurations and processes described herein and shown in the drawings, which can be varied in accordance with the particular needs of the application. For the sake of brevity, conventional techniques and methods related to making and using the application can not be described in detail herein. In the above embodiments, several specific steps are described and illustrated in order to provide a thorough understanding of the present application. However, the process of the present application can be practiced with less than all of the described and illustrated steps, or in a different order than that described and illustrated.

[0141] In the present application, features described and / or illustrated with respect to one embodiment can be used in the same or a similar way in one or more other embodiments, and / or in combination with or instead of features of other embodiments.

[0142] The above description is only preferred embodiments of the present application, and is not intended to limit the present application. The embodiments of the present application can be variously changed and modified by those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application should be included in the scope of the present application.

Claims

1. A ground penetrating radar transmit voltage dynamic adjustment system, characterized by, The system includes a separately configured transmitting antenna subsystem and a receiving antenna subsystem; The transmitting antenna subsystem includes: High-voltage module, used to provide high-voltage power; The pulse source module outputs a high-voltage pulse signal based on the high-voltage power supply and the trigger pulse; A transmitting antenna is used to convert the high-voltage pulse signal into a first electromagnetic wave and radiate it outwards; The receiving antenna subsystem includes: A receiving antenna for receiving an external second electromagnetic wave, the second electromagnetic wave including a direct wave and a reflected wave returning in the medium; The main control and data acquisition module is used to perform noise suppression, gain adjustment, imaging, and image optimization processing on the reflected wave; and to regulate the high-voltage power supply output by the high-voltage module by detecting the state of the direct wave through an analog-to-digital converter; wherein, the main control and data acquisition module controls a digital potentiometer through an FPGA chip to configure a control resistor for the high-voltage module to adjust the high-voltage power supply; the FPGA chip adjusts the digital potentiometer to decrease the level of the high-voltage power supply when the analog-to-digital converter is at full range and / or the direct wave is saturated, and adjusts the digital potentiometer to increase the level of the high-voltage power supply when the analog-to-digital converter is not at full range and / or the direct wave is not saturated.

2. The ground penetrating radar transmit voltage dynamic adjustment system of claim 1, wherein, The pulse source module consists of multiple avalanche diodes connected in series. Each avalanche diode is equipped with a parallel resistor and a capacitor at both ends to balance and limit overcurrent.

3. The ground penetrating radar transmit voltage dynamic adjustment system of claim 1, wherein, The high-voltage module employs a reference voltage divider adjustment structure. By using the digital potentiometer to set external first and second resistors, the fixed reference voltage of the high-voltage module is divided to adjust the voltage of the high-voltage power supply. The expression is: ； wherein, represents the fixed reference voltage, represents the first resistance, represents the second resistance.

4. The ground penetrating radar transmit voltage dynamic adjustment system of claim 3, wherein, The high-voltage module employs a feedback voltage divider adjustment structure. An external first resistor and a second resistor are configured via a digital potentiometer to form a feedback voltage divider network. Based on the voltage division ratio of this feedback voltage divider network, the voltage of the high-voltage power supply is adjusted according to a multiple of the high-voltage module's reference voltage. The expression is as follows: ； wherein, represents the reference voltage, represents the first resistance, represents the second resistance.

5. The ground penetrating radar transmit voltage dynamic adjustment system of claim 1, wherein, The system also includes: A distance adjustment mechanism is used to adjust the distance between the transmitting antenna and the receiving antenna; The user interaction module is used to control the distance adjustment mechanism to adjust the distance between the transmitting antenna and the receiving antenna based on the adjustment commands input by the user.

6. The ground penetrating radar transmit voltage dynamic adjustment system of claim 5, wherein, The distance adjustment mechanism includes: Slide rail; The first fixed base is fixedly mounted on the slide rail and is used to fix the transmitting antenna; The second fixed base is slidably mounted on the slide rail and is used to fix the receiving antenna. A drive motor is mounted on the second fixed base to drive the second fixed base to slide on the slide rail.

7. The ground penetrating radar transmit voltage dynamic adjustment system of claim 1, wherein, The FPGA chip adjusts the level of the high-voltage power supply based on a proportional-integral-derivative feedback control algorithm, including: comparing the current level value of the direct wave or the reflected wave with a target value, calculating an error , the calculation formula is: ； wherein denotes the target value, denotes the current level value; The regulating amount of the high-voltage power supply is: : ； wherein is a proportional coefficient, is an integral coefficient, is a derivative coefficient.

8. The ground penetrating radar transmit voltage dynamic adjustment system of claim 1, wherein, The FPGA chip, based on a policy network pre-trained using a reinforcement learning model, takes the voltage level of the high-voltage power supply, the voltage level of the direct wave, the dynamic range of the reflected wave, and the ratio of the dynamic range to the range of the analog-to-digital converter as inputs, and outputs an adjustment amount for the voltage level of the high-voltage power supply.

9. The ground-penetrating radar transmission voltage dynamic adjustment system according to claim 8, characterized in that, The pre-training steps of the policy network include: Construct a state space, which includes the level of the high-voltage power supply, the level of the direct wave, the dynamic range of the reflected wave, and the ratio of the dynamic range to the range of the analog-to-digital converter. Construct an action space, wherein the action space is the level adjustment amount of the high-voltage power supply; The policy network in reinforcement learning takes the parameters of the state space as input and outputs the level adjustment of the high-voltage power supply. The reward function is constructed by weighted summation of the direct wave unsaturation reward, dynamic range utilization reward and adjustment amplitude penalty. In multiple iterations, the parameters of the policy network are updated by minimizing the reward function until the reward function converges. The reward function R is calculated as follows: ； in, This indicates that the direct wave has not yet reached saturated rewards. This indicates a reward for dynamic range utilization. Indicates the penalty for the adjustment range; , and These are the weighting coefficients; ； ； ； Wherein, K represents the ratio of the dynamic range of the reflected wave to the range of the analog-to-digital converter. This indicates the level adjustment amount of the high-voltage power supply.

10. The ground-penetrating radar transmission voltage dynamic adjustment system according to claim 9, characterized in that, The policy network consists of a convolutional neural network and a fully connected network.

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