River full-section acoustic flow velocity measurement method and flow velocity meter

Abstract

The invention discloses a river full-section acoustic flow velocity measurement method and a flow velocity meter, the river full-section acoustic flow velocity measurement method combines a time difference method and a frequency difference method, utilizes the advantage of accurate measurement of the frequency difference method in a high flow velocity scene, makes up for the measurement insufficiency of the time difference method in high flow velocity, high sediment content and bubble content, and improves the measurement accuracy. The measurement precision in the wet season is improved, and flood disasters are warned in advance; the time-difference method has the advantages of accurate measurement and full-section measurement under normalization and low flow velocity. The two parts are measured in real time and are compared and verified, so that the high-precision measurement of the whole section is realized, and the section flow rate coverage rate is increased from 75-85% of the traditional ADCP to more than 98%; the vertical resolution reaches 0.1-0.5 m, and the transverse resolution reaches 1-5 m.

Description

Technical Field

[0001] This invention relates to the field of acoustic velocity measurement technology for the entire cross-section of rivers, specifically to a method for measuring acoustic velocity across the entire cross-section of rivers and a flow meter. Background Technology

[0002] There are many methods for measuring river flow velocity, which can be categorized by basic measurement principles into rotor-type current meters, buoy methods, radar current meters, mobile ADCP methods, fixed ADCP methods, time-of-flight ultrasonic current meters, and video image-based flow measurement methods. Among these methods, only ultrasonic time-of-flight current meters, multi-vertical rotor current meters, and mobile ADCP methods can achieve full-section flow velocity measurement. However, multi-vertical rotor current meters suffer from low efficiency and poor accuracy; mobile ADCP methods cannot provide real-time measurement and are expensive. Only ultrasonic time-of-flight current meters can perform real-time and economical full-section flow velocity measurement under normal and low flow conditions, with high measurement accuracy.

[0003] Time-of-flight ultrasonic river current meters are suitable for rivers with clear water and relatively low flow velocities, while frequency-difference ultrasonic current meters are suitable for rivers with floating debris and high flow velocities. However, the flow patterns of most rivers differ between the dry and wet seasons. During the dry season, the river flow velocity is low, the water is clear, and there are few suspended solids and air bubbles. The frequency-difference current meter receives low reflected echo energy, resulting in decreased measurement accuracy. During the wet season, the river flow velocity increases, the water becomes turbid, and there are more air bubbles and suspended solids, with a higher sediment content. The time-of-flight ultrasonic river current meter cannot penetrate the sediment, resulting in lower received echo energy and further reduced measurement accuracy.

[0004] The river cross-section acoustic current meter (time-difference method) demonstrates significant advancements compared to similar products both domestically and internationally in terms of flow velocity measurement accuracy, measurement range, and full-section flow velocity measurement capabilities. After more than two years of practical operation verification, it outperforms comparable products in terms of testing accuracy stability and environmental adaptability. Combining the frequency difference method with river cross-section flow velocity measurement represents a qualitative breakthrough in measurement methodology, enabling full-section, all-climate flow velocity measurement of rivers, giving it a strong competitive edge in the field of hydrological flow measurement instruments. Summary of the Invention

[0005] This invention provides a method for measuring the acoustic velocity of a river across its entire cross section, as well as a flow meter. By combining time difference and frequency difference methods to measure the velocity of a river cross section, it is possible to achieve the measurement of the velocity of a river across its entire cross section and in all weather conditions.

[0006] This invention provides the following technical solution: a method for measuring the acoustic velocity across the entire cross-section of a river, comprising: Step 1: using the cross-correlation method to measure the ultrasonic wave propagation time difference during time-of-flight (TOF) flow measurement to obtain a coarse time difference; Step 2: after preprocessing the signals from the host and slave devices during TOF flow measurement, performing complex demodulation, complex correlation processing, and phase difference extraction to obtain a fine time difference, and combining the coarse time difference to synthesize a high-precision ultrasonic wave propagation time difference to calculate the TOF flow velocity; Step 3: using the frequency difference method to calculate the point velocity to obtain a point velocity profile; Step 4: mapping the point velocity profile to the TOF measurement path, performing spatiotemporal alignment, and then performing dynamic weighted fusion to invert the actual river cross-sectional shape parameters to correct the geometric assumption error of the TOF flow velocity, and performing adaptive filtering on the point velocity calculated by the frequency difference method to achieve the measurement of the acoustic velocity across the entire cross-section of the river.

[0007] As an optional scheme for the river full-section acoustic velocity measurement method described in this invention, the following steps are taken to avoid interference between the time-of-flight method and the frequency difference method. When the river has a high sediment content, the frequency difference method is used as the main method, while for rivers with low sediment content and low flow velocity, the time-of-flight method is used as the main method. This achieves high-precision river full-section acoustic velocity by fusing dynamic velocity acquisition. In the data acquisition and processing process, specifically, in step one, the signals from the host and slave devices are sampled to obtain time-series signals during time-of-flight flow measurement. The correlation between the two corresponding time-series signals from the host and slave devices is calculated, and the time difference between the two time-series signals with the highest correlation is selected as the coarse time difference. In step two, the preprocessing includes: sequentially performing hardware amplification and filtering, AD sampling, and software bandpass filtering on the signals from the host and slave devices. During software bandpass filtering, the bandpass filter is selected based on the characteristics of the transducers of the host and slave devices and the frequency band of the transmitted signals. Complex demodulation includes multiplying the sequence signals of the master and slave transducers by complex exponential signals to obtain two sets of complex sequences. Complex correlation processing includes multiplying the complex sequences by their conjugates and summing them to obtain a complex number. The phase of the complex number is the phase difference measured by the master and slave transducers. Phase difference extraction includes calculating the phase difference of the complex number, converting the phase difference into a time difference to obtain the precise time difference. The high-precision ultrasonic propagation time is obtained by taking the integer part of the coarse time difference and the fractional part of the precise time difference. The frequency difference method for calculating point velocity includes obtaining the baseband signal through baseband complex demodulation, filtering out high-frequency carrier components through low-pass filtering, retaining the low-frequency signal containing Doppler information, obtaining the complex form of the signal by quadrature down-conversion before low-pass filtering, performing FFT transformation to convert the time domain signal to the frequency domain, extracting the Doppler frequency, and calculating the point velocity based on the Doppler frequency. In step four, during spatiotemporal alignment, GPS-PPS time tags are added to the data from the time difference method and the frequency difference method to achieve millisecond-level time synchronization. During dynamic weighted fusion, weights are dynamically allocated based on the signal-to-noise ratio, scatterer concentration, and cross-sectional regularity.

[0008] A current meter, employing any of the above-described methods for measuring the acoustic velocity of a river's entire cross-section, includes: a main unit and a slave unit. The main unit and slave unit cooperate to implement time-of-flight (TOF) flow measurement. The main unit includes a TOF flow measurement module one and a frequency difference flow measurement module, while the slave unit includes a TOF flow measurement module two. Each flow measurement module includes a transceiver transducer, which is electrically connected to a transceiver conversion module. The transceiver conversion module is connected to a transmitting circuit and a receiving circuit, respectively. The transmitting circuit and the receiving circuit are connected to a control processing circuit. The control processing circuits of TOF flow measurement module one and TOF flow measurement module two communicate wirelessly and are synchronized with the BeiDou Navigation Satellite System. The transceiver conversion module converts electrical signals into ultrasonic signals. The transmitting circuit and the receiving circuit are used for transmitting and receiving signals, respectively. The control processing circuit processes the received data to calculate the flow velocity. The transceiver transducer is a longitudinal transducer and is installed in a horizontally fixed manner. The transmitting circuit includes a driver circuit, a power amplifier circuit, and a matching circuit connected in sequence. The driver circuit uses two bootstrap power drivers to form a half-bridge driver circuit, which drives the full-bridge MOSFETs at the back end. The power amplifier circuit consists of four MOSFETs forming a full-bridge circuit to create two half-bridge circuits. The matching circuit includes an LC low-pass filter, a transformer, and a matching circuit. The power amplifier circuit is connected to the LC low-pass filter and the transformer, and the transformer is connected to the LC low-pass filter and the matching circuit. The matching circuit is connected to the transceiver transducer. The receiver circuit includes a preamplifier circuit, a gain control amplifier circuit, a filter circuit, an amplifier circuit, and an AD acquisition circuit connected in sequence. The receiver circuit amplifies the signal to above 40dB and filters out interference.

[0009] The present invention has the following beneficial effects:

[0010] 1. This method for measuring the acoustic velocity across the entire river cross-section combines the time-of-flight (TOF) method and the frequency difference method. The frequency difference method leverages its accuracy in high-velocity scenarios to compensate for the TOF method's limitations in high-velocity, high-sediment-content, and bubble-content conditions, thus improving measurement accuracy during high-water seasons and enabling early warning of floods. The TOF method, on the other hand, provides accurate measurements under normal and low-velocity conditions, offering the advantage of full-section measurement. Real-time measurements from both methods are compared and verified, achieving high-precision measurement across the entire cross-section. The cross-sectional velocity coverage is increased from 75%-85% with traditional ADCP to over 98%; the vertical resolution reaches 0.1-0.5m, and the lateral resolution reaches 1-5m.

[0011] 2. The combination of time difference method and frequency difference method in the full-section acoustic velocity measurement method of this river expands the applicable velocity range to 0.01-10m / s. Through algorithm fusion, the error of the single method is reduced when the sediment content is high and bubble interference occurs.

[0012] 3. The full-section acoustic velocity measurement method of this river dynamically calibrates the cross-sectional shape parameters using the profile data of the frequency difference method, thereby improving the applicability of the time difference method in floodplains, bends, and complex channels by more than 40%.

[0013] 4. The method for measuring the acoustic velocity across the entire river cross section is based on the dynamic allocation of transmission timing according to water quality parameters. A dual-mode time-division transmission protocol is developed to avoid mutual interference between the time difference method and the frequency difference method. When the sediment content of the river is high, the frequency difference method is used as the main method. For rivers with low sediment content and low flow velocity, the time difference method is used as the main method. The method achieves high-precision acoustic velocity across the entire river cross section by fusing dynamic velocity acquisition.

[0014] 5. This current meter can simultaneously measure the cross-sectional average velocity and vertical velocity distribution of a single device, eliminating the need for cross-validation with multiple devices and reducing anchoring / installation points by more than 50%. Adaptive acoustic frequency switching extends the equipment's lifespan in harsh environments. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the cross-correlation calculation results in Embodiment 1 of the present invention.

[0016] Figure 2 This is a schematic diagram of signal processing for baseband demodulation and low-pass filtering in Embodiment 1 of the present invention.

[0017] Figure 3 This is a schematic diagram of the flow meter in Embodiment 2 of the present invention.

[0018] Figure 4 This is a schematic diagram of the module connection of the transmitting circuit of the flow meter in Embodiment 2 of the present invention.

[0019] Figure 5 This is a schematic diagram of the module connection of the receiving circuit of the flow meter in Embodiment 2 of the present invention. Detailed Implementation

[0020] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0021] Example 1

[0022] Please see Figures 1-2One method for measuring the acoustic velocity across the entire river cross-section involves using the time-of-flight (TOF) method and the frequency difference method to avoid interference. When the river has a high sediment content, the frequency difference method is primarily used; for rivers with low sediment content and low flow velocity, the TOF method is primarily used. This allows for the fusion of dynamic velocity data to obtain a high-precision acoustic velocity measurement of the entire river cross-section. During data acquisition and processing, the key to measuring velocity using the TOF method lies in accurately measuring the ultrasonic wave propagation time. The more accurate the time measurement, the more accurate the measured velocity. This embodiment employs several algorithms to improve the accuracy of ultrasonic wave propagation time measurement, specifically:

[0023] Step 1: The coarse time difference is obtained by measuring the ultrasonic wave propagation time difference during time-of-flight flow measurement using the cross-correlation method. Specifically, the signals from the master and slave devices are sampled to obtain time-series signals during time-of-flight flow measurement. The correlation between the two corresponding time-series signals from the master and slave devices is calculated. The time difference between the two time-series signals with the highest correlation is the coarse time difference. The calculation results are as follows: Figure 1 As shown, the algorithm for cross-correlation to calculate propagation time has the advantage of including all sampled data in the statistics and calculations, effectively reducing the impact of environmental noise on measurement accuracy, reducing the requirements for transducer consistency and temperature drift, and improving measurement accuracy and stability.

[0024] Step 2: After preprocessing the signals from the master and slave devices during time-of-flight flow measurement, perform complex demodulation, complex correlation processing, and phase difference extraction to obtain the precise time difference. Combine the coarse time difference to synthesize the high-precision ultrasonic propagation time difference to calculate the flow velocity using the time-of-flight method. Specifically, during preprocessing, the signals from the master and slave devices are sequentially subjected to hardware amplification and filtering, AD sampling, and software bandpass filtering. During software bandpass filtering, a bandpass filter is selected based on the characteristics of the transducers of the master and slave devices and the frequency band of the transmitted signal. In this embodiment, the bandpass filter is selected with a passband frequency of 80-100kHz, a cutoff frequency of 70-110kHz, and a ripple of 0.5dB.

[0025] Complex demodulation includes multiplying the sequence signals a[n] and b[n] from the master and slave transducers, respectively, by exp(-j2πfc / fs[0,-N-1]) to obtain two sets of complex sequences Zb[n] and Zc[n]. Complex correlation processing includes multiplying the complex sequences by their conjugates and summing them to obtain a complex number. The phase of the complex number is the phase difference measured by the master and slave transducers. Phase difference extraction includes calculating the phase difference of the complex number, converting the phase difference into a time difference, and obtaining the precise time difference. The high-precision ultrasonic propagation time is obtained by taking the integer part of the coarse time difference and the fractional part of the precise time difference.

[0026] Step 3: Calculate the point velocity profile using the frequency difference method. Specifically, the frequency difference method for calculating point velocity includes: obtaining the baseband signal through baseband demodulation and then performing low-pass filtering, such as... Figure 2 As shown, the calculation formula is as follows: f(t) is the input signal. Multiplying f(t) by the sine function sin(wt) and the cosine function cos(wt) respectively yields the modulated signals x1(t) and x2(t). w is the signal frequency.

[0027] The formula for calculating a low-pass filter is as follows: The modulated signals x1(t) and x2(t) are filtered by a low-pass filter function h(t) to remove the high-frequency carrier component and retain the low-frequency signal containing Doppler information. Before low-pass filtering, the amplitude-modulated signal is obtained by quadrature down-conversion to obtain the complex form of the signal. Then, FFT transformation is performed to convert the time-domain signal to the frequency domain and extract the Doppler frequency. The Doppler frequency is found in the spectrum. Finally, the point flow velocity is calculated based on the Doppler frequency.

[0028] Step 4: Map the point velocity profile to the measurement path of the time-of-flight method, perform spatiotemporal alignment, and then perform dynamic weighted fusion. Invert the actual river cross-sectional shape parameters to correct the geometric assumption error of the time-of-flight method velocity. After adaptive filtering of the point velocity calculated by the frequency difference method, realize the full-section acoustic velocity measurement of the river.

[0029] When aligning time and space, GPS-PPS time tags are added to the data from the time difference method and frequency difference method to achieve millisecond-level time synchronization. When dynamically weighting and fusing, weights are dynamically allocated based on the signal-to-noise ratio, scatterer concentration, and cross-sectional regularity.

[0030] In this embodiment, the time-difference method calculates the average cross-sectional velocity by measuring the time difference between the forward and reverse propagation of sound waves, while the frequency difference method obtains the vertical velocity profile through Doppler frequency shift. The time-difference method compensates for the shortcomings of the frequency difference method in near-shore and surface / bottom blind zones, while the frequency difference method solves the problem that the time-difference method cannot obtain the vertical velocity distribution. Through this design, the cross-sectional velocity coverage is increased from 75%-85% of the traditional ADCP to over 98%; the vertical resolution reaches 0.1-0.5m, and the lateral resolution reaches 1-5m.

[0031] Furthermore, the method in this embodiment significantly improves data reliability under complex hydrological conditions. The time-of-flight method is sensitive to low flow velocities (less than 0.1 m / s), while the frequency difference method is highly stable in turbulent environments with high flow velocities (greater than 3 m / s). The combined method expands the applicable flow velocity range to 0.01-10 m / s. Through algorithm fusion, the errors of single methods are reduced when sediment content is high or bubble interference occurs. By dynamically calibrating the cross-sectional shape parameters using profile data from the frequency difference method, the applicability of the time-of-flight method in floodplains, bends, and complex channels is improved by more than 40%.

[0032] Example 2

[0033] Please see Figures 3-5 A flow meter, applying the acoustic flow velocity measurement method for the entire cross-section of a river as described in Example 1, includes: a master unit and a slave unit. The master unit and slave unit cooperate to implement time-of-flight flow measurement. The master unit includes a time-of-flight flow measurement module one and a frequency difference flow measurement module. The slave unit includes a time-of-flight flow measurement module two. Each flow measurement module includes a transceiver transducer. The transceiver transducer is electrically connected to a transceiver conversion module. The transceiver conversion module is connected to a transmitting circuit and a receiving circuit, respectively. The transmitting circuit and the receiving circuit are connected to a control processing circuit. The control processing circuits of the time-of-flight flow measurement module one and the time-of-flight flow measurement module two communicate wirelessly and are synchronized with BeiDou. The transceiver conversion module converts electrical signals into ultrasonic signals. The transmitting circuit and the receiving circuit are used to transmit and receive signals, respectively. The control processing circuit processes the received data to calculate the flow velocity.

[0034] The transceiver is a vertically mounted transceiver, installed horizontally for stable long-term operation. The transmitting circuit comprises a drive circuit, a power amplifier circuit, and a matching circuit connected in sequence. The drive circuit uses two bootstrap power drivers to form a half-bridge drive circuit, driving the full-bridge MOSFETs at the rear. The bootstrap power drivers generate the upper half-bridge power supply via a charge pump, simplifying the number and form of the driver power supply. The power amplifier circuit uses four MOSFETs in a full-bridge configuration to form two half-bridge circuits, improving the voltage output of the power amplifier circuit and reducing the power supply voltage requirements. The matching circuit includes an LC low-pass filter, a transformer, and a matching circuit. The power amplifier circuit connects to the LC low-pass filter and the transformer, which in turn connects to the LC low-pass filter and the matching circuit. The matching circuit connects to the transceiver, performing impedance transformation, transceiver phase matching, harmonic suppression, and other functions, enabling time-division dual-frequency acoustic wave transmission to avoid signal interference. The transmission timing is dynamically adjusted; frequency difference method is preferred for high sand content, while time difference method is preferred for low flow velocity. The receiver circuit is a crucial component of Doppler current measurement, primarily responsible for amplifying weak echo signals. It uses programmable gain control to condition the weak echo signals, amplifying them to the required voltage range, and filters out out-of-band interference signals to increase the signal-to-noise ratio of the received signal. Due to absorption losses, spread losses, and transducer directivity attenuation in water, the received echo signal is extremely small, only a few microvolts to a few millivolts, even smaller than the amplitude of interference noise. An amplification factor of 40dB or higher is required. The receiver circuit includes a preamplifier circuit, a gain control amplifier circuit, a filter circuit, an amplifier circuit, and an AD acquisition circuit connected in sequence. The receiver circuit amplifies the signal to above 40dB and filters out interference. This velocity meter can simultaneously measure the cross-sectional average flow velocity and vertical flow velocity distribution using a single device, eliminating the need for cross-verification with multiple devices and reducing anchoring / installation points by more than 50%.

[0035] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0036] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A method for measuring acoustic velocity across the entire cross-section of a river, characterized in that, include: Step 1: Obtain the coarse measurement time difference by measuring the ultrasonic wave propagation time difference during time difference flow measurement using the cross-correlation method; Step 2: After preprocessing the signals from the host and slave devices during time-of-flight flow measurement, perform complex demodulation, complex correlation processing, and phase difference extraction to obtain the precise time difference. Combine the coarse time difference to synthesize the high-precision ultrasonic wave propagation time difference to calculate the flow velocity using the time-of-flight method. Step 3: Calculate the point velocity using the frequency difference method to obtain the point velocity profile; Step 4: Map the point velocity profile to the measurement path of the time-of-flight method, perform spatiotemporal alignment, and then perform dynamic weighted fusion. Invert the actual river cross-sectional shape parameters to correct the geometric assumption error of the time-of-flight method velocity. After adaptive filtering of the point velocity calculated by the frequency difference method, realize the full-section acoustic velocity measurement of the river.

2. The method for measuring acoustic velocity across the entire river cross section according to claim 1, characterized in that: In step one, the signals of the master and slave devices are sampled to obtain time series signals when measuring flow using the time difference method. The correlation between the two time series signals corresponding to the master and slave devices is calculated, and the time difference between the two time series signals with the highest correlation is selected as the coarse measurement time difference.

3. The method for measuring the acoustic velocity across the entire river cross section according to claim 1 or 2, characterized in that: Step two preprocessing includes: performing hardware amplification and filtering, AD sampling, and software bandpass filtering on the signals from the master and slave devices in sequence. During software bandpass filtering, the bandpass filter is selected based on the characteristics of the transducers of the master and slave devices and the frequency band of the transmitted signal.

4. The method for measuring acoustic velocity across the entire river cross section according to claim 1, characterized in that: Complex demodulation includes multiplying the sequence signals of the master and slave transducers by complex exponential signals to obtain two sets of complex sequences; complex correlation processing includes multiplying the complex sequences by their conjugates and summing them to obtain a complex number, the phase of which is the phase difference measured by the master and slave transducers.

5. The method for measuring acoustic velocity across the entire river cross section according to claim 4, characterized in that: Phase difference extraction includes: calculating the phase difference of a complex number, converting the phase difference into a time difference, obtaining the precise time difference, and the high-precision ultrasonic propagation time is obtained by taking the integer part of the coarse time difference and the decimal part of the precise time difference.

6. The method for measuring acoustic velocity across the entire river cross section according to claim 1, characterized in that: The frequency difference method for calculating point flow velocity includes: obtaining the baseband signal through baseband complex demodulation, filtering out high-frequency carrier components through low-pass filtering, retaining the low-frequency signal containing Doppler information, obtaining the complex form of the signal by orthogonal down-conversion of the amplitude modulation signal before low-pass filtering, and then performing FFT transformation to convert the time domain signal to the frequency domain and extracting the Doppler frequency, and calculating the point flow velocity based on the Doppler frequency.

7. The method for measuring acoustic velocity across the entire river cross section according to claim 1, characterized in that: In step four, during spatiotemporal alignment, GPS-PPS time tags are added to the data from the time difference method and the frequency difference method to achieve millisecond-level time synchronization. During dynamic weighted fusion, weights are dynamically allocated based on the signal-to-noise ratio, scatterer concentration, and cross-sectional regularity.

8. A flow meter, employing the acoustic flow velocity measurement method for the entire cross-section of a river as described in any one of claims 1-7, characterized in that: include: The system consists of a master unit and a slave unit, which work together to implement time-of-flight (TOF) flow measurement. The master unit includes a TOF flow measurement module 1 and a frequency difference flow measurement module, while the slave unit includes a TOF flow measurement module 2. Each flow measurement module includes a transceiver transducer, which is electrically connected to a transceiver conversion module. The transceiver conversion module is connected to the transmitting circuit and the receiving circuit, respectively. The transmitting circuit and the receiving circuit are connected to a control processing circuit. The control processing circuits of TOF flow measurement module 1 and TOF flow measurement module 2 communicate wirelessly and are synchronized with BeiDou. The transceiver conversion module converts electrical signals into ultrasonic signals. The transmitting circuit and the receiving circuit are used to transmit and receive signals, respectively. The control processing circuit processes the received data to calculate the flow rate.

9. The flow meter according to claim 8, characterized in that: The transceiver is a vertical transceiver and is installed using a horizontal fixing method.

10. The flow meter according to claim 8, characterized in that: The transmitting circuit includes a driving circuit, a power amplifier circuit, and a matching circuit connected in sequence. The driving circuit uses two bootstrap power drivers to form a half-bridge driving circuit, which is used to drive the full-bridge MOSFETs at the back end. The power amplifier circuit is composed of four MOSFETs forming a full-bridge circuit to form two half-bridge circuits. The matching circuit includes an LC low-pass filter, a transformer, and a matching circuit. The power amplifier circuit is connected to the LC low-pass filter and the transformer. The transformer is connected to the LC low-pass filter and the matching circuit. The matching circuit is connected to the transceiver transducer. The receiver circuit includes a preamplifier circuit, a gain control amplifier circuit, a filter circuit, an amplifier circuit, and an AD acquisition circuit connected in sequence. The receiver circuit amplifies the signal to above 0dB and filters out interference.

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