A linear frequency modulation signal processing system and method for acoustic wave wireless transmission

Abstract

The present invention relates to a linear frequency modulation signal processing system and method for wireless acoustic wave transmission, which is characterized by comprising: a signal processing module for acquiring a linear frequency modulation signal of an acoustic wave and generating a sine pulse width modulation signal; an amplification circuit for amplifying the sine pulse width modulation signal; a driving circuit for driving the conduction state of the amplification circuit; a filtering circuit for filtering the amplified sine pulse width modulation signal and then outputting it to a load terminal for driving; a monitoring and feedback module for monitoring the filtered frequency signal, and the signal processing module acquires this frequency signal and uploads it. The present invention can be widely applied to the technical field of wireless acoustic logging instruments.

Description

Technical Field

[0001] The present invention relates to the technical field of wireless acoustic logging tools, and particularly to a linear frequency modulation (Chirp) signal processing system and method for wireless acoustic wave transmission. Background Art

[0002] With the continuous deepening of oil and gas exploration, the logging difficulty has become increasingly greater. The well depth has increased from about 1000 to 2000 meters originally to the current normal 3000 meters, and 5000 and 6000 meters for deep wells. There are problems of high risk and danger during the exploitation process. Therefore, if people want to accurately know the working conditions of downhole instruments during oil exploitation, it is necessary to transmit the real-time information downhole during the drilling process to the ground. Field workers can correctly evaluate the working conditions of downhole instruments by analyzing the real-time data transmitted by downhole instruments. Therefore, measurement while drilling and information transmission are one of the key technologies, and it is necessary to obtain data such as downhole pressure and downhole temperature in real time. Timely acquisition of this information is of great significance for accurately detecting the formation, geological structure, and oil reservoir reserves. Therefore, how to transmit downhole information to the wellhead and analyze it has always been a research hotspot in the oil industry.

[0003] The downhole information transmission methods can be divided into wired transmission and wireless transmission. The main methods of wired transmission include cable transmission, intelligent drill pipe transmission, and optical fiber transmission. Wired cable transmission is to send the logging instrument for the required parameters through the gap between the tubing and the casing into the wellbore through a seven-core or single-core logging cable, and transmit the obtained downhole information to the surface receiving device through the cable. This method does not require the use of a downhole power source, has a high transmission rate and can transmit information bidirectionally, and is not affected by well depth limitations and signal attenuation, etc. It is a widely used data transmission method at present. However, the biggest drawback of this method is that the logging instrument must be lowered to the bottom of the well through the cable after the work is stopped. Multiple tests need to be carried out within a year, which is extremely costly, and often due to the friction and collision between the cable and the oil well casing, the cable breaks, resulting in measurement failure. There are problems such as too high cost, complex structure connection, and poor versatility. The theoretical data transmission rate of intelligent drill pipe transmission and optical fiber transmission is much higher than that of acoustic wave transmission, but due to its high cost and complex technology, it is currently limited to the experimental research stage. Wireless transmission methods include mud pulse transmission, acoustic wave transmission, and electromagnetic wave transmission. At present, the commonly used method for downhole data transmission is mud pulse transmission. This method uses drilling fluid as the power, and converts the data collected downhole into a pressure signal through a downhole pulse generator, and transmits the pressure signal to the surface while drilling, and resolves the downhole data through the surface system. The advantage of this method is that it abandons the traditional special drill pipe and cable, and the disadvantage is that the transmission rate is not high and it is restricted by the drilling fluid. The electromagnetic wave transmission method is that the downhole instrument converts the collected data into a signal, and then the electromagnetic wave emits this signal to the surroundings. The surface system on the wellhead receives this electromagnetic wave signal and performs various signal processing to calculate the data collected downhole. The advantage of electromagnetic wave transmission is that the transmission rate is higher than that of mud pulse transmission, and no receiving device is required for bidirectional transmission, and it can be applied to ordinary drilling, foam drilling, and underbalanced drilling. However, the energy attenuation is large during electromagnetic wave transmission. The formation material is the carrier for electromagnetic wave transmission, and the formation medium situation has a greater impact on the signal. Especially the noise in the well site, which increases the difficulty of signal detection. The emergence of acoustic wave transmission while drilling solves some of the problems that occur in the above methods. Acoustic wave transmission while drilling uses acoustic wave signals as the transmission medium. When transmitting in the drill pipe channel, the unique frequency band characteristics in the drill string can allow specific frequency acoustic waves to be transmitted and the transmission rate is not low. It is an information transmission method with great potential. The advantage of using the acoustic wave transmission method to transmit downhole data is low cost, short time for the data signal to be transmitted to the surface, and not easily affected by the drilling fluid. However, whether it is acoustic wave transmission, electromagnetic transmission, or other transmission methods, they all face the same problem, that is, the signal will cause various attenuations during the downhole transmission process, resulting in the problem of short transmission distance. These problems have always troubled the researchers. If this problem is not solved, it will cause a lot of trouble to oil extraction.

[0004] As the core device for downhole acoustic wave emission, the power amplifier should have a wide power supply voltage range and a sufficient output current. At the same time, the device should have good temperature drift characteristics. In the existing technology, most of the pre-stage signals are generated by a dedicated digital frequency synthesis chip and then through a signal amplification circuit, which poses very strict requirements on the signal amplification circuit: it needs to have high voltage resistance, large output current, large output power consumption and high output efficiency. Such an integrated circuit chip has too many internal circuit structures and switching transistors, etc., resulting in not too large output power consumption of the chip. In actual work, it can only work within a relatively low voltage range, and the instantaneous working current is also very small. Summary of the Invention

[0005] In view of the above problems, the object of the present invention is to provide a linear frequency modulation signal processing system and method for acoustic wave wireless transmission that can work within a wide voltage range and has a large output current.

[0006] To achieve the above object, the present invention adopts the following technical solutions: On the one hand, a linear frequency modulation signal processing system for acoustic wave wireless transmission is provided, including:

[0007] A signal processing module for acquiring the linear frequency modulation signal of the acoustic wave and generating a sine pulse width modulation signal;

[0008] An amplification circuit for amplifying the sine pulse width modulation signal;

[0009] A drive circuit for driving the conduction state of the amplification circuit;

[0010] A filter circuit for filtering the amplified sine pulse width modulation signal and then outputting it to the load end for driving;

[0011] A monitoring and feedback module for monitoring the filtered frequency signal, and the signal processing module acquires this frequency signal and uploads it.

[0012] Further, the linear frequency modulation signal processing system further includes a clock module and a temperature sensor;

[0013] The clock module is used to represent the time of signal acquisition;

[0014] The temperature sensor is used to collect the working ambient temperature of the circuit.

[0015] Further, the amplification circuit adopts an H-bridge amplification circuit.

[0016] Further, the H-bridge amplification circuit includes a first field effect transistor, a second field effect transistor, a third field effect transistor and a fourth field effect transistor;

[0017] The gates of the first field-effect transistor, the second field-effect transistor, the third field-effect transistor, and the fourth field-effect transistor are respectively connected to the output terminal of the drive circuit; the drains of the first field-effect transistor and the third field-effect transistor are connected in parallel to the power supply, the sources of the first field-effect transistor and the third field-effect transistor, and the drains of the second field-effect transistor and the fourth field-effect transistor are connected in parallel to the filter circuit; the sources of the second field-effect transistor and the fourth field-effect transistor are respectively grounded.

[0018] Further, the first field-effect transistor, the second field-effect transistor, the third field-effect transistor, and the fourth field-effect transistor are all N-channel enhancement-mode field-effect transistors.

[0019] Further, the signal processing module includes:

[0020] A signal generation unit, configured to obtain a linear frequency modulation signal of a sound wave and generate a separated sine pulse width modulation signal through an internal PWM;

[0021] An ADC unit, configured to obtain the frequency signal of the linear frequency modulation signal;

[0022] A signal transmission unit, configured to upload the frequency signal obtained by the ADC unit through a communication module.

[0023] Further, the monitoring and feedback module includes:

[0024] An operational amplifier, configured to collect the frequency signal of the filtered circuit and perform filtering;

[0025] A level comparator, configured to generate a trigger pulse for enabling the ADC unit according to the signal processed by the operational amplifier.

[0026] Further, the communication module includes:

[0027] An RS485 interface, configured to communicate with an external sensor and a host computer;

[0028] An IIC module, configured to communicate with the clock module through the IIC protocol;

[0029] An SPI module, configured to communicate with the temperature sensor.

[0030] On the other hand, a method for processing a linear frequency modulation signal for wireless transmission of a sound wave is provided, including:

[0031] The signal processing module obtains a linear frequency modulation signal of a sound wave and generates a sine pulse width modulation signal;

[0032] The drive circuit drives the amplifier circuit to conduct, and the amplifier circuit amplifies the sine pulse width modulation signal;

[0033] The filter circuit filters the amplified sinusoidal pulse width modulation signal and outputs it to the load terminal for driving;

[0034] The monitoring and feedback module monitors the filtered frequency signal;

[0035] The signal processing module acquires the frequency signal and uploads it.

[0036] Furthermore, the signal processing module acquires the linear frequency modulation signal of the sound wave and generates a sinusoidal pulse width modulation signal, including:

[0037] The signal generation unit obtains the duty cycle parameter value of the internal PWM through internal timer interruption, and the PWM works for one cycle;

[0038] When the previous PWM in the signal generation unit finishes working, the duty cycle parameter of the next PWM is assigned to generate the next PWM waveform;

[0039] When one sine wave cycle ends, the PWM in the signal generation unit stops working, generating a discrete sinusoidal pulse width modulation signal.

[0040] Furthermore, the drive circuit drives the amplifier circuit to conduct, and the amplifier circuit amplifies the sinusoidal pulse width modulation signal, including:

[0041] The drive circuit controls the on-off states of the drains and sources of the first field effect transistor, the second field effect transistor, the third field effect transistor, and the fourth field effect transistor by driving the gates of the first field effect transistor, the second field effect transistor, the third field effect transistor, and the fourth field effect transistor;

[0042] The amplifier circuit shapes the discrete sinusoidal pulse width modulation signal and sends the shaped signal to the filter circuit.

[0043] Due to the above technical solutions adopted by the present invention, it has the following advantages:

[0044] 1. The present invention realizes the generation of the linear frequency modulation signal by adopting the SPWM method. The linear frequency modulation signal has a low frequency, so the wavelength is longer, which is more suitable for long-distance transmission.

[0045] 2. The amplifier circuit 2 provided by the present invention uses an H-bridge amplifier circuit to amplify the linear frequency modulation signal to excite greater energy.

[0046] 3. The linear frequency modulation signal of the present invention is a broadband swept frequency signal from 500 Hz to 1.5 KHz, which can well resist the frequency selective drop caused by the periodic pipe string.

[0047] 4. The technical solution of the present invention fully considers the limitations of the downhole application environment, and uses SPWM instead of DA to generate the linear frequency modulation signal, with low system power consumption and high reliability.

[0048] In summary, the present invention can be widely applied to the technical field of wireless acoustic logging tools. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] By reading the following detailed description of the preferred embodiments, various other advantages and benefits will become clear to those of ordinary skill in the art. The drawings are only for the purpose of showing the preferred embodiments and are not considered to be a limitation of the present invention. Throughout the drawings, the same reference numerals are used to denote the same components. In the drawings:

[0050] Figure 1 is a schematic structural diagram of a downhole acoustic two-way wireless transmission relay system in the prior art provided by an embodiment of the present invention;

[0051] Figure 2 is a schematic structural diagram of a linear frequency modulation signal processing system provided by an embodiment of the present invention;

[0052] Figure 3 is a schematic diagram of the driving signal waveform of a linear frequency modulation signal provided by an embodiment of the present invention;

[0053] Figure 4 is a schematic diagram of the voltage and current waveforms when a linear frequency modulation signal is working with a load provided by an embodiment of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0054] The exemplary embodiments of the present invention will be described in more detail below with reference to the drawings. Although the exemplary embodiments of the present invention are shown in the drawings, it should be understood that the present invention can be implemented in various forms and should not be limited by the embodiments described herein. On the contrary, these embodiments are provided so that the present invention can be more thoroughly understood and the scope of the present invention can be fully conveyed to those skilled in the art.

[0055] It should be understood that the terms used herein are only for the purpose of describing specific exemplary embodiments and are not intended to be limiting. Unless otherwise clearly indicated in the context, the singular forms "a", "an" and "the" as used herein may also include the plural forms. The terms "comprising", "including", "containing" and "having" are inclusive and thus specify the presence of the stated features, steps, operations, elements and / or components, but do not preclude the presence or addition of one or more other features, steps, operations, elements, components, and / or combinations thereof. The method steps, processes, and operations described herein are not to be construed as necessarily requiring them to be performed in the specific order described or illustrated, unless the execution order is clearly indicated. It should also be understood that additional or alternative steps may be used.

[0056] Although terms such as first, second, third, etc. may be used in the text to describe multiple elements, components, regions, layers, and / or sections, these elements, components, regions, layers, and / or sections should not be limited by these terms. These terms may be used only to distinguish one element, component, region, layer, or section from another region, layer, or section. Unless the context clearly indicates otherwise, terms such as "first", "second", and other numerical terms do not imply order or sequence when used in the text. Therefore, the first element, component, region, layer, or section discussed below may be referred to as the second element, component, region, layer, or section without departing from the teachings of the exemplary embodiments.

[0057] As Figure 1 shown, it is an example of the driving implementation of an underground acoustic two-way wireless transmission relay system disclosed in the prior art. Among them, the power amplification circuit uses the LM1875 high-voltage and high-current operational amplifier. The maximum supply voltage of the LM1875 is 60V, the maximum output power is 30W, and the static operating current is 50mA. When the output power reaches the critical value, the LM1875 will trigger the overheat protection mechanism to protect the normal operation of the circuit. Figure 1 The underground acoustic two-way wireless transmission relay system in has the phenomenon of overheating and crashing easily under high power. Therefore, the linear frequency modulation signal processing system and method for acoustic wireless transmission provided by the embodiments of the present invention generate a signal by a signal processing module, amplify the signal through an amplification circuit, and after passing through a filtering module, the output signal can drive the transducer of the load to work. The working voltage of the circuit of the present invention can reach up to 500V at most, the continuous working current can reach up to 5A at most, and the instantaneous working current can reach up to 25A at most. Compared with the traditional signal amplification circuit, the output power consumption of the present invention can be made very large. However, considering the actual power consumption of the transducer, the actual instantaneous power of the present invention is 500W, and the continuous working power is 270W, which can achieve the stable amplification of the linear frequency modulation signal, has a high power density and good high-temperature characteristics, and solves the problem of heat generation of the integrated operational amplifier in the prior art.

[0058] Embodiment 1

[0059] As Figure 2 shown, this embodiment provides a linear frequency modulation signal processing system for acoustic wireless transmission, including a signal processing module 1, an amplification circuit 2, a driving circuit 3, a filtering circuit 4, a monitoring and feedback module 5, and a communication module 6.

[0060] The signal processing module 1 is used to obtain the linear frequency modulation (chirp) signal of the acoustic wave and generate a discrete sine pulse width modulation (SPWM) signal.

[0061] The amplification circuit 2 is used to amplify the sine pulse width modulation signal.

[0062] The drive circuit 3 is used to drive the conduction state of the amplifier circuit 2.

[0063] The filter circuit 4 is used to filter the amplified sine pulse width modulation signal and then output it to the load terminal 7 for driving.

[0064] The monitoring feedback module 5 is used to monitor the frequency signal of the filtered circuit. This frequency signal is used to evaluate whether the frequency of the linear frequency modulation signal generated by the sine pulse width modulation signal meets the requirements. The signal processing module 1 acquires the frequency signal and uploads it through the communication module 6.

[0065] In a preferred embodiment, the linear frequency modulation signal processing system further includes a clock module, which is used to characterize the time of signal acquisition.

[0066] In a preferred embodiment, the linear frequency modulation signal processing system further includes a temperature sensor, which is used to collect the working environment temperature of the circuit. When the working environment temperature exceeds the limit, it protects the circuit.

[0067] In a preferred embodiment, the amplifier circuit 2 is an H-bridge amplifier circuit composed of a first field effect transistor a, a second field effect transistor b, a third field effect transistor c, and a fourth field effect transistor d.

[0068] The gates G of the first field effect transistor a, the second field effect transistor b, the third field effect transistor c, and the fourth field effect transistor d are respectively connected to the output terminal of the drive circuit 3. The drains D of the first field effect transistor a and the third field effect transistor c are connected in parallel to the power supply VCC. The sources S of the first field effect transistor a and the third field effect transistor c and the drains D of the second field effect transistor b and the fourth field effect transistor d are connected in parallel to the filter circuit 4. The sources S of the second field effect transistor b and the fourth field effect transistor d are respectively grounded.

[0069] Specifically, the first field effect transistor a, the second field effect transistor b, the third field effect transistor c, and the fourth field effect transistor d are all N-channel enhancement type field effect transistors, and their on-resistances are all in the two-digit milliohm level. In this way, the energy loss on the field effect transistor when the circuit is conducting is very small. The field effect transistors are selected as TO-252 surface mount packages. When two field effect transistors are placed together, their width is less than 20 mm, which is a prerequisite for realizing the miniaturization of the instrument.

[0070] Specifically, the peak voltage of the amplifier circuit 2 is determined by the voltage of the power supply VCC of the H-bridge, and at the same time, it also determines that the drain-source voltage of the first field effect transistor a, the second field effect transistor b, the third field effect transistor c, and the fourth field effect transistor d is greater than or equal to 1.5 times the VCC value, so as to ensure the stable and reliable operation of the circuit and save costs at the same time.

[0071] In a preferred embodiment, the signal processing module 1 includes a signal generation unit, a PWM (pulse width modulation) port, an ADC unit, and a signal transmission unit.

[0072] The signal generation unit is used to obtain the chirp signal of the acoustic wave, perform real-time data acquisition through the internal timer interruption, and generate a separated sine pulse width modulation signal through the internal PWM.

[0073] The PWM port is used to send the separated sine pulse width modulation signal to the drive circuit 3.

[0074] The ADC unit is used to obtain the frequency signal of the chirp signal.

[0075] The signal transmission unit is used to upload the frequency signal obtained by the ADC unit through the communication module 6.

[0076] In a preferred embodiment, the drive circuit 3 can adopt two driving chips of the H-bridge dedicated driving chips produced by IR Company. This driving chip has the advantages of optocoupler isolation and electromagnetic isolation, the characteristic of high voltage resistance and not being easily broken down. The internal structure of the chip adopts the bootstrap voltage structure form, its peripheral circuit structure is simple, the high voltage end uses a capacitor for energy storage, and it can drive two N-type field effect transistors, greatly saving the PCB layout space and providing convenient conditions for the miniaturization of the instrument and local heat dissipation treatment.

[0077] In a preferred embodiment, the filter circuit 4 can adopt an LC filter circuit 4.

[0078] In a preferred embodiment, the monitoring and feedback module 5 includes an operational amplifier and a level comparator. The operational amplifier is used to collect the frequency signal of the filtered circuit and perform filtering. The level comparator is used to generate a trigger pulse according to the signal processed by the operational amplifier, and this trigger pulse enables the ADC unit of the signal processing module 1 to complete the acquisition of a single chirp signal.

[0079] Specifically, the operational amplifier can adopt the operational amplifier with the model number AD8479 for signal monitoring and feedback. The common-mode voltage of this operational amplifier is 600V, which can meet the voltage withstand requirements of the peak voltage after voltage amplification of the H-bridge amplifier circuit 2.

[0080] In a preferred embodiment, the communication module 6 includes an RS485 interface 61, an IIC (Integrated Circuit Bus) module 62, and an SPI (Serial Peripheral Interface) module 63. The RS485 interface 61 is used to communicate with external sensors, the upper computer, etc., to realize data interaction and data calibration, etc. The IIC module 62 is used to communicate with the clock module through the IIC protocol to ensure the timeliness of data storage. The SPI module 63 is used to communicate with the temperature sensor.

[0081] In a preferred embodiment, the fundamental frequency of the amplifier circuit 2 is 20 KHZ, the carrier frequency is 1 KHz, and the cut-off frequency of the filter circuit 4 is 2 KHz.

[0082] As Figure 3 shown, it is a waveform schematic diagram of the linear frequency modulation signal driving signal, and this driving signal can be used to drive the H-bridge circuit to generate a linear frequency modulation signal; as Figure 4 shown, it is a waveform schematic diagram of the voltage and current when the linear frequency modulation signal is working with load. Among them, the peak-to-peak voltage is 200 V, the peak-to-peak current is 20 A (100 mV / A range), and its instantaneous power can reach 1000 W.

[0083] Embodiment 2

[0084] This embodiment provides a method for processing linear frequency modulation signals for acoustic wave wireless transmission, including the following steps:

[0085] 1) The signal processing module 1 acquires the linear frequency modulation signal of the acoustic wave and generates a separated sine pulse width modulation signal. Specifically:

[0086] 1.1) The signal generation unit obtains the duty cycle parameter value of the internal PWM through the internal timer interrupt, and the PWM works for one cycle.

[0087] 1.2) After the previous PWM in the signal generation unit finishes working, assign the duty cycle parameter of the next PWM to generate the next PWM waveform.

[0088] 1.3) When one sine wave cycle ends, the PWM in the signal generation unit stops working, and a separated sine pulse width modulation signal is generated in this process.

[0089] 1.4) The signal generation unit sends the separated sine pulse width modulation signal to the drive circuit 3 through the PWM port.

[0090] 2) The drive circuit 3 drives the amplifier circuit 2 to conduct, and the amplifier circuit 2 amplifies the separated sine pulse width modulation signal. Specifically:

[0091] 2.1) The drive circuit 3 drives the amplifier circuit 2 to conduct.

[0092] Specifically, the drive circuit 3 controls the on-off states of the drains D and sources S of the first field effect transistor a, the second field effect transistor b, the third field effect transistor c, and the fourth field effect transistor d by driving the gates G of them.

[0093] 2.2) The amplifier circuit 2 amplifies the separated sine pulse width modulation signal.

[0094] Specifically, the amplifier circuit 2 shapes the discrete sinusoidal pulse width modulation signal, and at the same time increases the driving ability of the discrete sinusoidal pulse width modulation signal, and then sends the shaped signal to the filter circuit 4 to complete the amplification of the discrete sinusoidal pulse width modulation signal.

[0095] 3) The filter circuit 4 filters the amplified SPWM signal and outputs it to the load terminal 7 for driving.

[0096] 4) The monitoring and feedback module 5 monitors the frequency signal of the filtered circuit, specifically:

[0097] 4.1) The operational amplifier collects the frequency signal of the filtered circuit and filters it to ensure the accuracy of the feedback signal sampling.

[0098] 4.2) The level comparator generates a trigger pulse according to the signal processed by the operational amplifier, enabling the ADC unit to complete the acquisition of a single chirp signal.

[0099] 5) The signal processing module 1 obtains the frequency signal and uploads it through the communication module 6, specifically:

[0100] 5.1) The ADC unit obtains the chirp signal frequency signal.

[0101] 5.2) The signal transmission unit uploads the frequency signal obtained by the ADC unit through the communication module 6.

[0102] The above embodiments are only used to illustrate the present invention. The structures, connection methods, manufacturing processes, etc. of each component can be changed. Any equivalent transformation and improvement based on the technical solution of the present invention should not be excluded from the protection scope of the present invention.

Claims

1. A linear frequency modulation signal processing system for wireless acoustic wave transmission, characterized in that Including: A signal processing module, configured to obtain a chirp signal of a sound wave and generate a sine pulse width modulation signal; An amplifier circuit, configured to amplify the sine pulse width modulation signal; A drive circuit, configured to drive the on-state of the amplifier circuit; A filter circuit, configured to filter the amplified sine pulse width modulation signal and then output it to a load terminal for driving; A monitoring and feedback module, configured to monitor the filtered frequency signal, and the signal processing module obtains this frequency signal and uploads it; This chirp signal processing system further includes a clock module and a temperature sensor; The clock module is used to represent the time of signal acquisition; The temperature sensor is used to collect the operating ambient temperature of the circuit; The signal processing module includes: A signal generation unit, configured to obtain a chirp signal of a sound wave and generate a separated sine pulse width modulation signal through internal PWM; An ADC unit, configured to obtain the frequency signal of the chirp signal; A signal transmission unit, configured to upload the frequency signal obtained by the ADC unit through a communication module.

2. The linear frequency modulation signal processing system for acoustic wave wireless transmission according to claim 1, characterized in that The amplifier circuit adopts an H-bridge amplifier circuit.

3. A linear frequency modulation signal processing system for acoustic wave wireless transmission according to claim 2, characterized in that, The H-bridge amplifier circuit includes a first field effect transistor, a second field effect transistor, a third field effect transistor, and a fourth field effect transistor; The gates of the first field effect transistor, the second field effect transistor, the third field effect transistor, and the fourth field effect transistor are respectively connected to the output terminal of the drive circuit; the drains of the first field effect transistor and the third field effect transistor are connected in parallel to a power supply, and the sources of the first field effect transistor and the third field effect transistor and the drains of the second field effect transistor and the fourth field effect transistor are connected in parallel to the filter circuit; The sources of the second field effect transistor and the fourth field effect transistor are respectively grounded.

4. The linear frequency modulation signal processing system for acoustic wave wireless transmission according to claim 3, characterized in that, The first field effect transistor, the second field effect transistor, the third field effect transistor, and the fourth field effect transistor are all N-channel enhancement type field effect transistors.

5. A chirp signal processing system for acoustic wave wireless transmission according to claim 1, characterized in that, The monitoring and feedback module includes: An operational amplifier, configured to collect the frequency signal of the filtered circuit and perform filtering; A level comparator, configured to generate a trigger pulse for enabling the ADC unit according to the signal processed by the operational amplifier.

6. A method for processing a chirp signal for acoustic wave wireless transmission in a chirp signal processing system for acoustic wave wireless transmission according to any one of claims 3 to 4, characterized in that, Including: The signal processing module obtains a chirp signal of a sound wave and generates a sine pulse width modulation signal; The drive circuit drives the amplifier circuit to conduct, and the amplifier circuit amplifies the sine pulse width modulation signal; The filter circuit filters the amplified sine pulse width modulation signal and then outputs it to a load terminal for driving; The monitoring and feedback module monitors the filtered frequency signal; The signal processing module obtains this frequency signal and uploads it.

7. The linear frequency modulation signal processing method for acoustic wave wireless transmission according to claim 6, characterized in that, The signal processing module obtains a chirp signal of a sound wave and generates a sine pulse width modulation signal, including: The signal generation unit obtains the duty cycle parameter value of the internal PWM through internal timer interruption, and the PWM works for one cycle; When the previous PWM in the signal generation unit ends, the duty cycle parameter of the next PWM is assigned to generate the next PWM waveform; When one sine wave cycle ends, the PWM in the signal generation unit stops working, generating a separated sine pulse width modulation signal.

8. A chirp signal processing method for acoustic wave wireless transmission according to claim 6, characterized in that, The drive circuit drives the amplifier circuit to conduct, and the amplifier circuit amplifies the sine pulse width modulation signal, including: The drive circuit controls the on-off states of the drains and sources of the first field-effect transistor, the second field-effect transistor, the third field-effect transistor, and the fourth field-effect transistor by driving the gates of the first field-effect transistor, the second field-effect transistor, the third field-effect transistor, and the fourth field-effect transistor; The amplifier circuit shapes the discrete sinusoidal pulse width modulation signal and sends the shaped signal to the filter circuit.

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