A resonant high-sensitivity sound pressure detection hydrophone and its implementation method

Abstract

This invention belongs to the field of underwater acoustics, specifically relating to a resonant high-sensitivity sound pressure detection hydrophone and its implementation method. The resonant high-sensitivity sound pressure detection hydrophone utilizes a resonant sensitivity mechanism, performing narrow-band high-sensitivity resonant sensing only for specific sound field characteristic information. It possesses narrow-band high-sensitivity characteristics, and by combining it with a broadband hydrophone to obtain background noise for threshold setting, effective detection of specific sound field characteristic information can be achieved. Utilizing the inherent resonant characteristics of the hydrophone's sensitive structure, the inherent resonant frequency of the sensitive structure is used as the hydrophone's operating frequency. Through the design of the sensitive structure's intrinsic frequency point and the corresponding structural damping design, narrow-band filtering sensing and resonant high-sensitivity response characteristics near the predetermined characteristic frequency point are achieved. This invention is used for the detection of specific frequency characteristic information underwater.

Description

Technical Field

[0001] This invention belongs to the field of underwater acoustics, specifically relating to a resonant high-sensitivity sound pressure detection hydrophone and its implementation method. Background Technology

[0002] In the field of sensor technology, to date, the vast majority of sensors have been designed as linear sensors with the goal of measurement. Most applications require linear measurements, emphasizing static measurements and prioritizing accuracy. For example, pressure sensors typically have specific technical specifications including sensitivity, bandwidth, and three accuracy indicators (nonlinearity, repeatability, and hysteresis) or five accuracy indicators (nonlinearity, repeatability, hysteresis, time drift, and temperature drift). Underwater acoustic sensors are no exception; most maintain this design philosophy. Evaluation metrics for underwater acoustic sensors employing this linear sensing design primarily include bandwidth, intra-band sensitivity and flatness, and response consistency. Because acoustic signals contain rich frequency components, their measurement is dynamic. Therefore, the flatness of the frequency response and the ability to guarantee linear measurement are crucial for obtaining accurate values ​​of the measured signal. The design of underwater acoustic sensors also requires linear response characteristics to obtain accurate linear measurements of the sound source information, providing accurate and linearly convertible front-end input information for subsequent sonar signal processing.

[0003] With the rapid development of IoT and microelectronics technologies, sensor technology and its application models have undergone significant changes, and sensor design concepts are facing innovation and transformation. Advances in microelectronics and the maturity of micro-integration capabilities have also provided more possibilities for sensor fusion design. Against this backdrop of sensor technology development, foreign countries have taken the lead in breaking through conventional sensor technologies and application paradigms by proposing a novel feature-wake-up sensing mode and application paradigm based on target detection. This innovative idea stems from the strong demand for a large number of sensors with extremely low power consumption in IoT field applications. Its core innovative concept is to fully acquire various feature information of the measured object from multiple angles using sensor technology, and then output the acquired feature information through special signal processing to drive subsequent operations. This type of sensor emphasizes information acquisition rather than measurement, focusing on whether feature information is obtained rather than the accuracy of measurement.

[0004] In underwater acoustic applications, the useful acoustic signals received by underwater acoustic sensors are very weak due to the presence of background noise in the marine environment. In many cases, they are submerged in the noise. Especially when detecting at a distance, the acoustic signals emitted by the sound source that the underwater acoustic sensor can receive are extremely weak and are definitely submerged in the background noise. Under these circumstances, there is an urgent need for sensors with high sensitivity.

[0005] Structural resonance, as a physical phenomenon, has played a significant role and achieved many unique effects under certain special conditions through ingenious utilization. Examples include surface acoustic wave (SAW) devices and bulk wave devices. Similarly, in the field of hydrophones, resonance characteristics are applied to hydrophone design. However, to date, resonance characteristics are generally used to design active sound sources, and are rarely used in the design of passively receiving hydrophones. This is because the receiving end requires the hydrophone to maintain stable and consistent sound across a wide frequency range, and resonant points are usually eliminated or avoided. Therefore, this paper proposes a high-sensitivity sound pressure detection hydrophone utilizing structural resonance characteristics, along with its design and operating method, enabling highly sensitive detection of characteristic information. Summary of the Invention

[0006] The present invention also provides a resonant high-sensitivity sound pressure hydrophone for detecting specific sound field characteristics underwater.

[0007] The present invention also provides a method for implementing a resonant high-sensitivity sound pressure hydrophone, which is used to obtain a resonant high-sensitivity sound pressure hydrophone and simultaneously realize the transmission of monitoring and processing of specific underwater sound field characteristic information.

[0008] This invention is achieved through the following technical solution:

[0009] This invention provides a design method for a resonant, high-sensitivity sound pressure hydrophone, the design method comprising the following steps:

[0010] A resonant high-sensitivity sound pressure detection hydrophone utilizes a resonant sensitivity mechanism to perform narrowband high-sensitivity resonant sensing only for specific sound field feature information. It has narrowband high-sensitivity characteristics. When combined with a broadband hydrophone to obtain background noise and set a threshold, it can effectively detect specific sound field feature information.

[0011] By utilizing the inherent resonant characteristics of the hydrophone's sensitive structure and taking the inherent resonant frequency of the sensitive structure as the operating frequency of the hydrophone, narrowband filtering sensing and high-sensitivity resonant response characteristics near the predetermined characteristic frequency point are achieved through the design of the intrinsic frequency point of the sensitive structure and the design of structural damping.

[0012] A design method for a resonant, high-sensitivity sound pressure hydrophone, the design method comprising the following steps:

[0013] Step 1: Select frequency points for specific underwater acoustic field characteristics based on the detection requirements;

[0014] Step 2: Select the sensitive mode and sensitive structure of the hydrophone based on the characteristic frequency point, and use the sensitive structure that senses the sound information as a resonator, and use the frequency of the characteristic information to be detected as the resonant frequency of the sensitive structure, so that the resonant frequency of the sensitive structure is the same as the characteristic frequency.

[0015] Step 3: Based on the operating frequency of the resonant hydrophone in Step 2, design the parameters of the acoustic pressure hydrophone resonator, that is, design the parameters of the sensitive structure;

[0016] Step 4: Based on the sensitive structure obtained in Step 2 and the parameters of the sensitive structure obtained in Step 3, design the mechanical response of the sensitive structure, and design the force-to-electric converter accordingly to obtain the sensitivity response of the hydrophone.

[0017] Step 5: Damping design. Based on the bandwidth requirements of the hydrophone, the damping coefficient is designed, and the acoustic encapsulation structure is selected as the damping structure according to the structural characteristics to obtain the overall structure of the resonant high-sensitivity sound pressure detection hydrophone.

[0018] Furthermore, based on the method of designing sensitive structure parameters according to characteristic frequencies, the natural frequency expression of the sensitive structure can be derived from elasticity theory.

[0019]

[0020] Where k is the stiffness of the elastic sensing element; m is the equivalent vibration mass;

[0021] By selecting parameters for the sensitive structure, its inherent resonant frequency is made consistent with the frequency of the underwater measured characteristic information.

[0022] Furthermore, based on the dynamic response theory of elasticity, the acoustic pressure mechanical response sensitivity of the resonant high-sensitivity acoustic pressure hydrophone is designed, specifically including the following steps.

[0023] Step 4.1: Perform stress analysis on the selected sensitive structure and establish mechanical equations based on the theory of elasticity;

[0024] Step 4.2: Solve the equation;

[0025] Step 4.3: Based on the solution of the obtained equation, take the first-order resonant frequency to obtain the mechanical response expression;

[0026] Step 4.4: Based on the mechanical response expression in Step 4.3, obtain the mechanical response distribution diagram of the sensitive structure;

[0027] Step 4.5: Based on the distribution diagram of the mechanical response of the sensitive structure, design the force-to-electric converter. Specifically, design the type, distribution location, and area of ​​the force-to-electric converter according to the characteristics of the stress concentration area.

[0028] Furthermore, step 5 specifically involves the following: when a sound field is present, the sound pressure is incident perpendicularly onto the upper surface of the flat diaphragm sensitive structure through the damping encapsulation structure 4. The damping encapsulation structure 4 broadens the frequency band. By designing a damping coefficient between 0 and 0.7, a resonant high-sensitivity sound pressure hydrophone with different response amplitudes and a -3dB frequency band width can be achieved.

[0029] A resonant high-sensitivity sound pressure detection hydrophone is provided. The hydrophone is designed using the design method described above and then manufactured and assembled in modules to achieve its structural composition and working method. The resonant high-sensitivity sound pressure detection hydrophone includes a mechanically sensitive resonator 1, a force-to-electric converter 2, an electrical signal extraction module 3, a damping encapsulation structure 4, an electrical signal processing module 5, a housing structure 6, leads 7, and an output structure 8.

[0030] The mechanically sensitive resonator 1 is positioned above the electrical signal processing module 5. A force-to-electric converter 2 is mounted on the mechanically sensitive resonator 1, and an electrical signal extraction module 3 is mounted on the force-to-electric converter 2. The electrical signal extraction module 3 is connected to the electrical signal processing module 5, and the electrical signal processing module 5 is connected to the output structure 8 via lead wires 7. A damping encapsulation structure 4 is filled between the mechanically sensitive resonator 1 and the housing structure 6.

[0031] Furthermore, the damping encapsulation structure 4 is used to suppress the amplitude of the sharp resonant peak at the frequency point of the acquired feature information to be detected, while simultaneously widening the bandwidth.

[0032] The mechanically sensitive resonator 1 is used to receive acoustic signals at characteristic frequency points of underwater information to be detected.

[0033] The force-to-electric converter 2 is used to convert the mechanical changes of the mechanically sensitive resonator 1 into charge signals through the piezoelectric effect;

[0034] The electrical signal extraction module 3 is used to extract the charge signal output by the force-to-electric converter 2;

[0035] The electrical signal processing module 5 filters and amplifies the charge signal extracted by the electrical signal extraction module 3.

[0036] The lead 7 is used to transmit the information extracted by the electrical signal extraction module 3 to the electrical signal processing module 5, and to transmit the electrical signal processed by the electrical signal processing module 5 to the output structure 8.

[0037] The output structure 8 is used to output the information received by the resonant high-sensitivity detection acoustic pressure hydrophone.

[0038] The housing structure 6 is used to ensure the stability of the internal structure of the resonant high-sensitivity sound pressure hydrophone, so that it can work normally underwater.

[0039] Furthermore, the signal forms processed by the electrical signal processing module 5 include, but are not limited to, charge signals, and can also be voltage, resistance, or capacitance signals;

[0040] The electrical signal processing module 5 filters, amplifies, and outputs signals of different forms, such as converted charges.

[0041] Furthermore, the resonant high-sensitivity sound pressure hydrophone can be implemented by using sensitive elements such as piezoelectric ceramics through electromechanical structure design, or it can be designed and implemented on a chip using MEMS technology. Multiple resonant high-sensitivity sound pressure hydrophones can also be integrated using MEMS integration technology.

[0042] This means that multiple sensitive resonators can be integrated and manufactured simultaneously on the same sensitive chip. When there are multiple resonators, each resonator needs to be equipped with an information extraction signal processing module. Therefore, the electrical signal processing module 5 can be implemented by integrating N independent information extraction signal processing modules to achieve simultaneous acquisition of multiple underwater feature information.

[0043] Furthermore, the working method involved in the sound field feature information sensing principle is as follows: when there is sound field feature information containing a certain feature frequency underwater, if the frequency of the feature information matches the working frequency band of the resonant high-sensitivity detection hydrophone, the resonance of the internal sensitive structure of the high-sensitivity detection sound pressure hydrophone is excited.

[0044] When resonance occurs, the sensitive structure generates charge or voltage signals through force-to-electricity conversion. After signal processing, the signals are output, achieving high-sensitivity sensing of narrow-band characteristic signals near the hydrophone's resonant frequency. When there are no characteristic signals, the hydrophone output is the background noise.

[0045] The beneficial effects of this invention are:

[0046] This invention detects only specific acoustic field characteristics and utilizes a resonance-sensitive mechanism, which is completely different from the detection methods used in the industry.

[0047] This invention is more sensitive, has better detection results, and faster information processing speed, saving a lot of time and resources for subsequent work. Attached Figure Description

[0048] Figure 1 This is a flowchart of the design method of the present invention.

[0049] Figure 2 This is a schematic diagram of the structure of the present invention.

[0050] Figure 3 This is a radial deflection response distribution diagram of the first-order resonant flat diaphragm with peripheral fixed support according to the present invention.

[0051] Figure 4 This is a schematic diagram of the amplitude response and bandwidth of the damped adjustable acoustic pressure hydrophone of the present invention. Detailed Implementation

[0052] 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.

[0053] This embodiment describes a high-sensitivity hydrophone designed using the resonant characteristics of a sensitive structure. Specifically, it utilizes the inherent resonant characteristics of the sensitive structure and designs the intrinsic frequency points and structural damping of the sensitive structure to achieve a high-sensitivity detection hydrophone with a certain bandwidth and high-sensitivity response near a predetermined characteristic frequency point.

[0054] A resonant high-sensitivity sound pressure detection hydrophone utilizes a resonant sensitivity mechanism to perform narrowband high-sensitivity resonant sensing only for specific sound field feature information. It has narrowband high-sensitivity characteristics. When combined with a broadband hydrophone to obtain background noise and set a threshold, it can effectively detect specific sound field feature information.

[0055] By utilizing the inherent resonant characteristics of the hydrophone's sensitive structure and taking the inherent resonant frequency of the sensitive structure as the operating frequency of the hydrophone, narrowband filtering sensing and high-sensitivity resonant response characteristics near the predetermined characteristic frequency point are achieved through the design of the intrinsic frequency point of the sensitive structure and the design of structural damping.

[0056] A design method for a resonant, high-sensitivity sound pressure hydrophone, the design method comprising the following steps:

[0057] Step 1: Select frequency points for specific underwater acoustic field characteristics based on the detection requirements;

[0058] Step 2: Select the sensitive mode and sensitive structure of the hydrophone according to the characteristic frequency point, and take the sensitive structure that senses the sound information as resonator 1, and take the frequency of the characteristic information to be detected as the resonant frequency of the sensitive structure, so that the resonant frequency of the sensitive structure is the same as the characteristic frequency.

[0059] Step 3: Based on the operating frequency of the resonant hydrophone in Step 2, design the parameters of the acoustic pressure hydrophone resonator 1, that is, design the parameters of the sensitive structure.

[0060] Step 4: Based on the sensitive structure obtained in Step 2 and the parameters of the sensitive structure obtained in Step 3, design the mechanical response of the sensitive structure, and design the force-to-electric converter accordingly to obtain the sensitivity response of the hydrophone.

[0061] Step 5: Damping design. Based on the bandwidth requirements of the hydrophone, the damping coefficient is designed, and the acoustic encapsulation structure is selected as the damping structure according to the structural characteristics to obtain the overall structure of the resonant high-sensitivity sound pressure detection hydrophone.

[0062] Furthermore, the specific operating frequency of the resonant hydrophone in step 2 involves designing a sound pressure hydrophone with high sensitivity response by utilizing the inherent resonant characteristics of the sensitive structure; using the sensitive structure as a resonator and its inherent resonant frequency as the operating frequency of the hydrophone, so that the hydrophone operates within a narrow frequency range centered on the inherent resonant frequency of the sensitive structure; and designing the resonant frequency of the sensitive structure according to the frequency points of the characteristic information to be detected, so that the resonant frequency of the sensitive structure is the same as the characteristic frequency.

[0063] Furthermore, the sensitive structure that senses acoustic information is used as a resonator. The frequency design of the resonator is achieved by designing the intrinsic frequency point of the sensitive structure. The mechanical sensitive structure resonator 1 of the acoustic bar hydrophone includes, but is not limited to, a peripherally fixed flat diaphragm. Since the resonant frequency of bending vibration is relatively low, the frequency design method is illustrated by taking the natural frequency design of a high-sensitivity acoustic bar hydrophone using a bending vibration mode with a peripherally fixed flat diaphragm sensitive structure as an example:

[0064] Taking a peripherally fixed flat diaphragm, according to the thin-plate theory of elasticity (Sensor Technology Handbook), the natural frequency expression of the peripherally fixed flat diaphragm sensing structure is:

[0065]

[0066] Where k is the stiffness of the elastic sensing element of the flat membrane structure, in N / m; m is the equivalent vibrating mass of the flat membrane structure, in kg; E is the elastic modulus of the flat membrane structure material, in Pa; μ is the Poisson's ratio of the flat membrane structure material; and ρ is the density of the flat membrane structure material, in kg / cm³. 3 ;

[0067] By selecting the material, radius, and thickness of the flat diaphragm, its inherent resonant frequency is made consistent with the frequency of the underwater measured characteristic information.

[0068] Furthermore, step 4 specifically involves designing the acoustic pressure mechanical response sensitivity of the resonant high-sensitivity acoustic pressure hydrophone based on the dynamic response theory of elasticity, specifically including the following steps:

[0069] Step 4.1: Assume the circular plate is fixed around its perimeter. When it is not subjected to external pushing force, it will generate free vibration after being initially excited. Through force analysis, the mechanical equations are established based on the theory of elasticity.

[0070]

[0071] Where ζ is the instantaneous displacement distribution function; σ0 = hρ0 is the mass per unit area; D is the cylindrical deflection of the plate.

[0072] Step 4.2: Solve the equations based on the thin-plate theory of elasticity;

[0073]

[0074] In the formula ω and Let be the angular frequency and amplitude distribution function of the normal vibration, and let the amplitude distribution function be...

[0075]

[0076] Step 4.3: Based on the solution of the obtained equation, take the first-order resonant frequency to obtain the mechanical response expression;

[0077] Ignoring circumferential resonance, when n = 0, the response is the first radial resonant frequency.

[0078]

[0079] in

[0080]

[0081] Step 4.4: Based on the mechanical response expression in Step 4.3, obtain the mechanical response distribution diagram of the sensitive structure;

[0082] Step 4.5: Based on the distribution diagram of the mechanical response of the sensitive structure, design the force-to-electric converter. Specifically, design the type, distribution location, and area of ​​the force-to-electric converter according to the characteristics of the stress concentration area.

[0083] When R(a) = 0, the sensitive structure is in a resonant state, and the amplitude tends to be infinite.

[0084] When acoustic field characteristics are present, the sound pressure is incident perpendicularly through the acoustic encapsulation structure onto the upper surface of the flat diaphragm sensitive structure, which is equivalent to applying a uniform acoustic pressure load p0 on the flat diaphragm structure. When the characteristic frequency of the acoustic field characteristics is the same as the natural frequency of the sensitive diaphragm, the sensitive structure will resonate, undergo bending deformation, and generate internal strain and stress changes, resulting in displacement deflection. When the first-order resonant frequency in the free state is excited, the resonant deflection response distribution at the first-order resonant frequency can be obtained, such as... Figure 3 As shown.

[0085] Furthermore, step 5 specifically involves taking a peripherally fixed flat diaphragm sensitive structure as an example. When a sound field is applied, the sound pressure is perpendicularly incident on the upper surface of the flat diaphragm sensitive structure through the damping encapsulation structure 4, which is equivalent to applying a damper to the flat diaphragm structure. Without a damping structure, the diaphragm is easily damaged due to large amplitude. Therefore, a damping structure is needed to limit the amplitude. The damping encapsulation structure 4 suppresses the sharp resonance peak amplitude and broadens the frequency band. By designing a damping coefficient between 0 and 0.7, a high-sensitivity sound pressure hydrophone with different response amplitudes and a -3dB frequency band width can be achieved.

[0086] A resonant high-sensitivity sound pressure detection hydrophone is designed using the design method described above, and its structure and operation are achieved through modular manufacturing and assembly. The resonant high-sensitivity sound pressure detection hydrophone includes a mechanically sensitive resonator 1, a force-to-electric converter 2, an electrical signal extraction module 3, a damping encapsulation structure 4, an electrical signal processing module 5, a housing structure 6, leads 7, and an output structure 8.

[0087] The mechanically sensitive resonator 1 is positioned above the electrical signal processing module 5. A force-to-electric converter 2 is mounted on the mechanically sensitive resonator 1. An electrical signal extraction module 3 is mounted on the force-to-electric converter 2. The electrical signal extraction module 3 is connected to the electrical signal processing module 5 and the electrical signal processing module 5 is connected to the output structure 8 via lead wires 7. A damping encapsulation structure 4 is filled between the mechanically sensitive resonator 1 and the housing structure 6.

[0088] Furthermore, the damping encapsulation structure 4 is used to suppress the amplitude of the sharp resonant peak at the frequency point of the acquired feature information to be detected, while simultaneously widening the bandwidth.

[0089] The mechanically sensitive resonator 1 is used to receive acoustic signals at characteristic frequency points of underwater information to be detected.

[0090] The force-to-electric converter 2 is used to convert the frequency received by the mechanically sensitive structure resonator 1 into a signal change that can be electrically extracted. In this embodiment, aluminum nitride piezoelectric thin film material is used to convert the mechanical changes of the sensitive structure into charge signals through the piezoelectric effect.

[0091] The information extraction module 3 is used to extract the change in the electrical signal converted by the force-to-electric converter 2;

[0092] The electrical signal processing module 5 filters and amplifies the charge signal extracted by the electrical signal extraction module 3.

[0093] The lead 7 is used to transmit the information extracted by the electrical signal extraction module 3 to the electrical signal processing module 5, and to transmit the electrical signal processed by the electrical signal processing module 5 to the output structure 8.

[0094] The output structure 8 is used to output the information received by the resonant high-sensitivity detection acoustic pressure hydrophone.

[0095] The housing structure 6 is used to ensure the stability of the internal structure of the resonant high-sensitivity sound pressure hydrophone, so that it can work normally underwater.

[0096] Furthermore, the signal forms processed by the information processing module 5 include, but are not limited to, charge signals, voltage, resistance, or capacitance;

[0097] The information processing module 5 performs extraction, filtering, amplification, and output processing on the converted signals in different forms.

[0098] Furthermore, the resonant high-sensitivity sound pressure hydrophone can be implemented by using sensitive elements such as piezoelectric ceramics through electromechanical structure design, or it can be designed and implemented on a chip using MEMS technology. Multiple resonant high-sensitivity sound pressure hydrophones can also be integrated using MEMS integration technology.

[0099] This means that multiple sensitive resonators can be integrated and manufactured simultaneously on the same sensitive chip. When there are multiple resonators, each resonator needs to be equipped with an information extraction signal processing module. Therefore, the electrical signal processing module 5 can be implemented by integrating N independent information extraction signal processing modules to achieve simultaneous acquisition of multiple underwater feature information.

[0100] The present invention also provides a working method for a resonant high-sensitivity sound pressure hydrophone. The working method based on the sound field feature information sensing principle is as follows: when there is sound field feature information containing a certain feature frequency underwater, if the frequency of the feature information matches the working frequency band of the resonant high-sensitivity sound pressure hydrophone, the resonance of the internal sensitive structure of the high-sensitivity sound pressure hydrophone is excited.

[0101] When resonance occurs, the sensitive structure generates charge or voltage signals through force-to-electricity conversion. After signal processing, the signals are output, achieving high-sensitivity detection of narrowband characteristic signals near the hydrophone's resonant frequency. When there are no characteristic signals, the hydrophone output is the background noise.

[0102] This invention detects only the characteristic information of sound pressure, making the entire detection process more sensitive, the detection effect better, and the information processing speed faster, saving a lot of time and signal processing resources for subsequent work.

Claims

1. A design method for a resonant high-sensitivity sound pressure hydrophone, characterized in that, The resonant high-sensitivity sound pressure hydrophone utilizes a resonant sensitivity mechanism, performing narrowband high-sensitivity resonant sensing only for specific sound field feature information. It has narrowband high-sensitivity characteristics and, in conjunction with a broadband hydrophone, obtains background noise for threshold setting to achieve effective detection of specific sound field feature information. By utilizing the inherent resonant characteristics of the sensitive structure of a hydrophone, the inherent resonant frequency of the sensitive structure is used as the operating frequency of the hydrophone. Through the design of the intrinsic frequency point of the sensitive structure and the structural damping matching design, narrowband filtering sensing and high resonant response characteristics near the predetermined characteristic frequency point are achieved. The design method includes the following steps: Step 1: Select frequency points for specific underwater acoustic field characteristics based on the detection requirements; Step 2: Select the sensitive mode and sensitive structure of the hydrophone according to the characteristic frequency point. The sensitive structure that senses the sound information is the resonator (1). The frequency of the characteristic information to be detected is taken as the resonant frequency of the sensitive structure, so that the resonant frequency of the sensitive structure is the same as the characteristic frequency. Step 3: Based on the operating frequency of the resonant hydrophone in Step 2, design the parameters of the resonator (1) of the acoustic pressure hydrophone, that is, design the parameters of the sensitive structure. Step 4: Based on the sensitive structure obtained in Step 2 and the parameters of the sensitive structure obtained in Step 3, design the mechanical response of the sensitive structure, and design the force-to-electric converter accordingly to obtain the sensitivity response of the hydrophone. Step 4.1: Assume the circular plate is fixed around its perimeter. When it is not subjected to external pushing force, it will generate free vibration after being initially excited. Through force analysis, the mechanical equations are established based on the theory of elasticity. （1） in, Let be the instantaneous displacement distribution function; , Mass per unit area; For the cylindrical surface deflection of the plate, ; Step 4.2: Solve the equations based on the thin-plate theory of elasticity; （2） In the formula and Let be the angular frequency and amplitude distribution function of the normal vibration. The amplitude distribution function is: （3） Step 4.3: Based on the solution of the obtained equation, take the first-order resonant frequency to obtain the mechanical response expression; Neglecting resonance in the circumferential direction, when When , it is the response at the first radial resonant frequency; （4） in , (5) （6） Step 4.4: Based on the mechanical response expression in Step 4.3, obtain the mechanical response distribution diagram of the sensitive structure; Step 4.5: Based on the distribution diagram of the mechanical response of the sensitive structure, design the force-to-electric converter. Specifically, design the type, distribution location, and area of ​​the force-to-electric converter according to the characteristics of the stress concentration area. Step 5: Damping design. Based on the bandwidth requirements of the hydrophone, the damping coefficient is designed, and the acoustic encapsulation structure is selected as the damping structure according to the structural characteristics to obtain the overall structure of the resonant high-sensitivity sound pressure detection hydrophone.

2. The design method of a resonant high-sensitivity sound pressure hydrophone according to claim 1, characterized in that, The method of designing sensitive structure parameters based on characteristic frequencies, according to elasticity theory, yields the following expression for the natural frequency of the sensitive structure: (0) in, k The stiffness of the elastic sensitive element; m Equivalent vibration mass; By selecting parameters for the sensitive structure, its inherent resonant frequency is made consistent with the frequency of the underwater measured characteristic information.

3. The design method of a resonant high-sensitivity sound pressure hydrophone according to claim 1, characterized in that, Specifically, step 5 involves the sound pressure acting perpendicularly onto the upper surface of the flat diaphragm sensitive structure through the damping encapsulation structure (4) when there is a sound field. The damping encapsulation structure (4) broadens the frequency band. By designing the damping coefficient between 0 and 0.7, a resonant high-sensitivity sound pressure hydrophone with different response amplitudes and a -3dB frequency band width can be realized.

4. A resonant high-sensitivity hydrophone for detecting acoustic pressure, characterized in that, The resonant high-sensitivity sound pressure detection hydrophone is obtained by the design method of the resonant high-sensitivity sound pressure detection hydrophone as described in claim 1. The hydrophone includes a mechanically sensitive resonator (1), a force-to-electric converter (2), an electrical signal extraction module (3), a damping encapsulation structure (4), an electrical signal processing module (5), a housing structure (6), leads (7), and an output structure (8). The mechanically sensitive resonator (1) is positioned above the electrical signal processing module (5). A force-to-electric converter (2) is mounted on the mechanically sensitive resonator (1). An electrical signal extraction module (3) is mounted on the force-to-electric converter (2). The electrical signal extraction module (3) and the electrical signal processing module (5) are connected by leads (7) to each other and to the output structure (8). A damping encapsulation structure (4) is filled between the mechanically sensitive resonator (1) and the shell structure (6).

5. The resonant high-sensitivity sound pressure hydrophone according to claim 4, characterized in that, The damping encapsulation structure (4) is used to suppress the amplitude of the sharp resonant peak at the frequency point of the acquired feature information to be detected, while widening the bandwidth. The mechanically sensitive resonator (1) is used to receive the acoustic signal at the characteristic frequency point of the underwater information to be detected. The force-to-electric converter (2) is used to convert the mechanical changes of the mechanically sensitive resonator (1) into charge signals through the piezoelectric effect; The electrical signal extraction module (3) is used to extract the charge signal output by the force-to-electric converter (2); The electrical signal processing module (5) filters and amplifies the charge signal extracted by the electrical signal extraction module (3); The lead wire (7) is used to transmit the information extracted by the electrical signal extraction module (3) to the electrical signal processing module (5) and to transmit the electrical signal processed by the electrical signal processing module (5) to the output structure (8). The output structure (8) is used to output the information received by the resonant high-sensitivity detection acoustic pressure hydrophone. The shell structure (6) is used to ensure the stability of the internal structure of the resonant high-sensitivity sound pressure hydrophone, so that it can work normally underwater.

6. A resonant high-sensitivity sound pressure hydrophone according to claim 4 or 5, characterized in that, The electrical signal processing module (5) processes signals including but not limited to charge signals, and may also be voltage, resistance or capacitance signals. The electrical signal processing module (5) filters, amplifies, and outputs signals of different forms of converted charge.

7. The resonant high-sensitivity sound pressure hydrophone according to claim 4, characterized in that, The resonant high-sensitivity sound pressure hydrophone can be implemented by using piezoelectric ceramic sensing elements through electromechanical structure design, or by designing and implementing it on a chip using MEMS technology. Multiple resonant high-sensitivity sound pressure hydrophones can also be integrated using MEMS integration technology. That is, multiple sensitive resonators can be integrated and manufactured on the same sensitive chip at the same time; when there are multiple resonators, each resonator needs to be equipped with an information extraction signal processing module. Therefore, the electrical signal processing module (5) can be implemented by the integration of N independent information extraction signal processing modules to achieve the simultaneous acquisition of multiple underwater feature information.

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