Sound pressure and water pressure signal integrated receiving device

Abstract

The invention discloses a sound pressure and water pressure signal integrated receiving device which comprises an upper piezoelectric ceramic ring of a sound pressure sensor, a lower piezoelectric ceramic ring of a water pressure sensor and a supporting body. The upper piezoelectric ceramic ring and the lower piezoelectric ceramic ring are stacked on the support body up and down, the upper piezoelectric ceramic ring and the lower piezoelectric ceramic ring are encapsulated on the support body and form an integrated structure with the support body, and the acoustic sensor sensitive element is positioned above the water pressure sensor sensitive element. Therefore, the sound signal receiving surface of the sound sensor is relatively far away from the instrument cabin body, the influence of sound wave reflection on the installation end surface of the instrument cabin is reduced, the baffle effect is reduced, and the directivity of the sound sensor in the actual use environment is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of underwater signal reception, and particularly relates to an integrated receiving device for sound pressure and water pressure signals. Background Art

[0002] Under normal circumstances, the perception and reception of underwater acoustic signals and water pressure signals are realized by using piezoelectric ceramic sensors. Both the acoustic sensor and the water pressure sensor of the piezoelectric ceramic type receive underwater acoustic and water pressure signals by sensing the pressure change acting on the surface of the piezoelectric sensitive element. According to the division of the underwater acoustics research field, the water pressure signal generally refers to the low-frequency signal in the frequency band of 0.1 Hz to 0.25 Hz, and the underwater acoustic signal generally refers to the medium and high-frequency signal above 16 Hz. It can be seen that although both are mechanical pressure waves, there are obvious differences in the working frequency bands. Therefore, in the field of underwater acoustics, underwater acoustic signals and water pressure signals are usually distinguished. Generally, multi-physical field signal acquisition devices also collect underwater acoustic signals and water pressure signals as different physical quantities separately.

[0003] To achieve the synchronous and co-point reception of underwater acoustic and water pressure signals, the acoustic sensor and the water pressure sensor usually need to be installed adjacent to each other on the underwater platform instrument cabin of the multi-physical field signal acquisition device. Among them, for the acoustic sensor, the instrument cabin itself and the adjacent water pressure sensor installed nearby have a baffle effect, which affects the receiving directivity of the acoustic sensor. On the other hand, for the water pressure sensor, the acoustic sensor is installed adjacent to the instrument cabin and protrudes from the surface of the instrument cabin. When there is water flow, it causes non-uniform changes in the underwater flow field, thereby interfering with and affecting the reception of water pressure signals. Summary of the Invention

[0004] In view of this, the present invention provides an integrated receiving device for sound pressure and water pressure signals, which can efficiently complete the integrated reception of sound pressure and water pressure signals.

[0005] The specific technical solution adopted by the present invention is as follows:

[0006] An integrated receiving device for sound pressure and water pressure signals, comprising: an upper piezoelectric ceramic ring of a sound pressure sensor, a lower piezoelectric ceramic ring of a water pressure sensor, and a support body; the upper piezoelectric ceramic ring and the lower piezoelectric ceramic ring are stacked on the support body up and down; the upper piezoelectric ceramic ring and the lower piezoelectric ceramic ring are potted on the support body and form an integrated structure with the support body.

[0007] Further, a latex gasket is arranged between the upper piezoelectric ceramic ring and the lower piezoelectric ceramic ring.

[0008] Further, the support body includes: an upper cover plate, a lower cover plate, and a base; annular grooves are provided on the upper cover plate, the lower cover plate, and the base; the upper piezoelectric ceramic ring is disposed between the annular grooves of the upper cover plate and the annular grooves of the lower cover plate, and the lower piezoelectric ceramic ring is disposed between the annular grooves of the lower cover plate and the base.

[0009] Further, the annular groove is filled with polyurethane or a latex gasket.

[0010] Further, the upper cover plate is connected to the lower cover plate, and the lower cover plate is connected to the base by screws.

[0011] Further, the base is a hollow cavity structure, and a signal conditioning circuit board is disposed in the cavity of the base, and the signal conditioning circuit board is used to condition the sound pressure signal and the water pressure signal.

[0012] Further, the support body further includes a rear cover plate, and the rear cover plate is connected to the base by screws.

[0013] Further, the material of the base is metal.

[0014] Further, it further includes: an upper wire and a lower wire, the upper wire is used to lead out the positive and negative electrodes of the upper piezoelectric ceramic ring, and the lower wire is used to lead out the positive and negative electrodes of the lower piezoelectric ceramic ring.

[0015] Further, the negative electrodes of the upper piezoelectric ceramic ring and the lower piezoelectric ceramic ring are connected to the ground in common with the base; the positive electrodes of the upper piezoelectric ceramic ring and the lower piezoelectric ceramic ring are connected to the dual-channel input end of the signal conditioning circuit board.

[0016] Advantageous effects:

[0017] (1) The present invention provides an integrated receiving device for sound pressure and water pressure signals, including: an upper piezoelectric ceramic ring of a sound pressure sensor, a lower piezoelectric ceramic ring of a water pressure sensor, and a support body; the upper piezoelectric ceramic ring and the lower piezoelectric ceramic ring are stacked on the support body up and down, and the upper piezoelectric ceramic ring and the lower piezoelectric ceramic ring are potted on the support body to form an integrated structure with the support body. The sound sensor sensitive element is located above the water pressure sensor sensitive element. In this way, the sound signal receiving surface of the sound sensor is relatively far from the instrument cabin body, reducing the influence of the sound wave reflection on the installation end surface of the instrument cabin, which is beneficial to reducing the baffle effect and improving the directivity of the sound sensor in the actual use environment.

[0018] (2) The upper cover plate, the lower cover plate and the base are all provided with annular grooves. The upper piezoelectric ceramic ring is arranged between the annular groove of the upper cover plate and the annular groove of the lower cover plate, and the lower piezoelectric ceramic ring is arranged between the annular grooves of the lower cover plate and the base. A damping washer made of damping material is used for decoupling and vibration isolation, so that the two ceramic rings are in the boundary conditions of free vibration, and the coupling interference between the ceramic rings is reduced.

[0019] (3) The base is a hollow cavity structure, and a signal conditioning circuit board is arranged in the cavity of the base. The sound and water pressure sensitive elements, the signal conditioning circuit board and the base form a closed mechatronic structure, which shortens the length of the grounding loop and the signal transmission line, and moreover, the metal base forms electromagnetic shielding for the signal conditioning circuit board, reducing the interference and noise of the signal conditioning circuit. Description of the Drawings

[0020] Figure 1 is a schematic structural installation diagram of the sound and water pressure integrated receiver according to an embodiment of the present invention;

[0021] Figure 2 is a schematic diagram of the piezoelectric ceramic ring sensitive device of the sound channel according to an embodiment of the present invention;

[0022] Figure 3 is a schematic diagram of the piezoelectric ceramic ring sensitive device of the water pressure channel according to an embodiment of the present invention;

[0023] Figure 4 is a schematic circuit diagram of the sound pressure channel according to an embodiment of the present invention;

[0024] Figure 5 is a schematic circuit diagram of the water pressure channel according to an embodiment of the present invention. Detailed Embodiments

[0025] The following are specific embodiments of the present invention with reference to the accompanying drawings, and the present invention will be described in detail.

[0026] An embodiment of the present invention provides a sound pressure and water pressure signal integrated receiving device, including: an upper piezoelectric ceramic ring of a sound pressure sensor, a lower piezoelectric ceramic ring of a water pressure sensor, and a support body; the upper piezoelectric ceramic ring and the lower piezoelectric ceramic ring are stacked on the support body up and down; the upper piezoelectric ceramic ring and the lower piezoelectric ceramic ring are potted on the support body and form an integrated structure with the support body.

[0027] In an exemplary embodiment, a latex washer is arranged between the upper piezoelectric ceramic ring and the lower piezoelectric ceramic ring.

[0028] In an exemplary embodiment, the support body includes: an upper cover plate, a lower cover plate, and a base; the upper cover plate, the lower cover plate, and the base are all provided with annular grooves, the upper piezoelectric ceramic ring is disposed between the annular grooves of the upper cover plate and the lower cover plate, and the lower piezoelectric ceramic ring is disposed between the annular grooves of the lower cover plate and the base.

[0029] In an exemplary embodiment, the annular groove is filled with polyurethane or a latex gasket.

[0030] In the actual implementation process, the piezoelectric ceramic sensitive elements of the acoustic and water pressure sensors are installed using an integrated structure: the piezoelectric ceramic sensitive elements of the acoustic and water pressure sensors are stacked up and down and installed on the same support substrate. The sensitive element of the acoustic sensor is located above the sensitive element of the water pressure sensor. In this way, the sound signal receiving surface of the acoustic sensor is relatively far from the instrument cabin body, reducing the influence of the acoustic wave reflection on the installation end surface of the instrument cabin, which is beneficial to reducing the baffle effect and improving the directivity of the acoustic sensor in the actual use environment. Secondly, the acoustic sensor is located directly above the water pressure sensor. Compared with the installation method of lateral separation for direction measurement, the influence on the underwater flow field is relatively uniform, which is beneficial to the reception of the water pressure signal. At the same time, after the acoustic and water pressure sensors adopt an integrated structure, the two mounting hole seats are combined into one, reducing the sealing link, which is of great significance for the use, maintenance, and maintenance of underwater products.

[0031] In the actual implementation process, since both the acoustic sensor and the water pressure sensor use piezoelectric ceramic elements as sensitive structures, an integrated structure is adopted. The piezoelectric sensitive elements of the acoustic and water pressure sensors are installed on the same substrate, and through decoupling and vibration isolation measures, the coupling between the acoustic and water pressure sensitive elements is suppressed, achieving the purpose of synchronously and co-point receiving and perceiving the acoustic and water pressure signals in the underwater sound field and water pressure field.

[0032] In an exemplary embodiment, the upper cover plate is connected to the lower cover plate, and the lower cover plate is connected to the base by screws.

[0033] In an exemplary embodiment, the base is a hollow cavity structure, and a signal conditioning circuit board is disposed in the cavity of the base. The signal conditioning circuit board is used to condition the sound pressure signal and the water pressure signal.

[0034] In an exemplary embodiment, the support body further includes a rear cover plate, and the rear cover plate is connected to the base by screws.

[0035] In an exemplary embodiment, the material of the base is metal.

[0036] In an exemplary embodiment, it further includes: an upper wire and a lower wire. The upper wire is used to lead out the positive and negative electrodes of the upper piezoelectric ceramic ring, and the lower wire is used to lead out the positive and negative electrodes of the lower piezoelectric ceramic ring.

[0037] In an exemplary embodiment, the negative electrodes of the upper piezoelectric ceramic ring and the lower piezoelectric ceramic ring are connected to the ground in common with the base; the positive electrodes of the upper piezoelectric ceramic ring and the lower piezoelectric ceramic ring are connected to the dual-channel input end of the signal conditioning circuit board.

[0038] In the actual implementation process, since the piezoelectric ceramic type sensor sensitive device has high resistance and capacitance, its output impedance is related to the static capacitance and operating frequency of the piezoelectric element: the lower the static capacitance of the piezoelectric element and the lower the operating frequency, the higher the output impedance. Since the frequency of the water pressure signal is much lower than the frequency of the acoustic signal, the sensitive element of the water pressure sensor should select a piezoelectric ceramic element with a static capacitance much larger than that of the acoustic sensor; considering the integrity of signal acquisition, according to Thevenin's theorem, the high output impedance of the sensor itself means that the input impedance of the subsequent conditioning circuit is required to be higher. Usually, the input impedance of the subsequent conditioning circuit is required to reach more than 10 times the output impedance of the previous-stage sensor. At the same time, in order to take into account the purpose of controlling the thermal noise of the input-stage resistor, the signal conditioning circuits matched with the acoustic and water pressure sensors are respectively designed according to the impedance characteristics of their sensitive elements.

[0039] Similarly, since the piezoelectric sensitive element is a capacitive device, the distributed capacitance on the signal transmission line connecting the sensitive element and the signal conditioning circuit causes loss of the sensor sensitivity when amplifying the output signal of the sensitive element. Therefore, it is necessary to shorten the length of the signal transmission line as much as possible to reduce the distributed capacitance on the line.

[0040] In view of these situations, taking advantage of the working principle that the piezoelectric ceramic type acoustic sensor and water pressure sensor receive acoustic and water pressure signals by sensing the pressure change on the surface of the piezoelectric sensitive element, and the characteristic that the signal frequency bands are extremely different, the piezoelectric ceramic sensitive elements of the acoustic and water pressure sensors are stacked and installed on the same support substrate up and down, and vibration damping washers are used between the sensitive elements for decoupling and vibration isolation to achieve the purpose of synchronously receiving and sensing acoustic and water pressure signals underwater; the signal conditioning circuit board is installed in the cavity of the sensitive element support substrate to form a mechatronic structure, shortening the length of the signal transmission line and reducing the sensitivity loss caused by the distributed capacitance on the line. The output signals of the piezoelectric ceramic sensitive elements of the acoustic and water pressure sensors are respectively conditioned by medium and low frequency signals and then output to the subsequent stage to obtain acoustic and water pressure signals respectively.

[0041] The object of the present invention is to reduce the interference between the acoustic and water pressure sensors when they are separately installed, reduce the influence of the baffle effect of the instrument cabin of the underwater installation platform on the directivity of the acoustic sensor, reduce the installation hole seats and watertight joints. After decoupling and vibration isolation of the piezoelectric ceramic sensitive elements of the acoustic and water pressure sensors through vibration damping washers, they are integrally vulcanized and sealed to the support substrate with rubber to form an integrated structure; a signal conditioning circuit board is installed in the cavity of the metal base of the support substrate to form an electromechanical integrated structure, reducing the loss of signal transmission lines and shielding electromagnetic interference; the signal conditioning circuit simultaneously completes the impedance matching and frequency division processing of the high output impedance of the acoustic and water pressure sensitive elements through an integral feedback loop, and outputs the acoustic and water pressure signals to the subsequent stage respectively.

[0042] According to the characteristics that the static capacitance of the piezoelectric ceramic element is relatively higher and the output impedance is relatively lower, and aiming at the requirement of the water pressure sensor to work in the extremely low frequency band of 0.1 Hz to 0.25 Hz, a thin-walled piezoelectric ceramic ring with large size and low resonance frequency is made of PMgN-51 type piezoelectric material with high dielectric constant as the sensitive element of the water pressure signal receiving channel, so as to increase the static capacitance of the element itself and further reduce the output impedance of the sensitive element; a thick-walled piezoelectric ceramic ring with small size and high resonance frequency is used as the sensitive element of the acoustic signal receiving channel to expand the working bandwidth of the acoustic receiving channel.

[0043] The piezoelectric ceramic ring of the water pressure channel and the piezoelectric ceramic ring of the acoustic channel are stacked up and down, and a vibration damping washer made of damping material is used for decoupling and vibration isolation, so that the two ceramic rings are in the boundary condition of free vibration, reducing the coupling interference between the ceramic rings. The sensitive elements of the two piezoelectric ceramic rings are potted on the base with polyurethane or vulcanized rubber. The base is made of light alloy material. The negative electrodes of the sensitive elements of the two piezoelectric ceramic rings are in contact with the alloy base to form a common ground wire; the signal conditioning circuit board is fixed in the cavity at the lower part of the base, and the signal reference ground of the circuit board is also connected to the alloy base - since the acoustic and water pressure sensitive elements, the signal circuit board and the base form a closed electromechanical integrated structure, the length of the grounding loop and the signal transmission line is shortened, and the metal base forms electromagnetic shielding for the signal conditioning circuit, reducing the interference and noise of the signal conditioning circuit.

[0044] Figure 1 It is a structural installation schematic diagram of the acoustic and water pressure integrated receiver according to the embodiment of the present invention, as Figure 1As shown, the small cover plate 1 (i.e., the upper cover plate in the above-mentioned embodiment) gently presses and fixes the upper piezoelectric ceramic ring 2 of the sound channel on the lower cover plate 4. Both the small cover plate 1 and the lower cover plate 4 are processed with annular grooves, and elastic latex gaskets or polyurethane are filled in the annular grooves as vibration isolation and decoupling materials. The upper piezoelectric ceramic ring 2 is placed on the vibration isolation and decoupling materials. On the one hand, it is in a free vibration boundary condition when receiving underwater sound signals. On the other hand, the vibration coupling interference between the upper piezoelectric ceramic ring 2 and the lower piezoelectric ceramic ring 5 is reduced. The upper wire 3 is a twisted pair wire, which leads out the positive and negative poles of the upper piezoelectric ceramic ring 2, etc. The lower cover plate 4 gently presses and fixes the lower piezoelectric ceramic ring 5 of the water pressure channel on the base 8. The base 8 is also processed with an annular groove and vibration isolation and decoupling materials, so that the lower piezoelectric ceramic ring 5 of the water pressure channel works under free vibration boundary conditions and reduces coupling interference. The lower wire 7 is a twisted pair wire, which leads out the positive and negative poles of the upper piezoelectric ceramic ring 2, etc. Among them, the negative lead wire ends of the lower wire 7 and the upper wire 3 are fastened to the base 8 with screws. The base 8 is made of lightweight alloy. Thus, the negative poles of the upper piezoelectric ceramic ring 2 and the lower piezoelectric ceramic ring 5 are connected to the ground in common with the base 8. The preamplifier circuit board 9 (i.e., the signal conditioning circuit board in the above-mentioned embodiment) is fixed on the rear cover plate 10 made of lightweight alloy. The copper-clad grounding layer of the preamplifier circuit board 9 is connected to the rear cover plate 10 through tightened metal screws. After the rear cover plate 10 is connected to the base 8 with screws, the copper-clad grounding layer of the preamplifier circuit board 9 is also connected to the ground in common with the base 8.

[0045] The positive poles of the upper piezoelectric ceramic ring 2 and the piezoelectric ceramic ring 5 are respectively connected to the dual-channel input ends of the preamplifier circuit board 9 through the positive lead wires of the lower wire 7 and the upper wire 3. The positive pole of the upper piezoelectric ceramic ring 2 is connected to the sound channel of the preamplifier circuit board 9, and the positive pole of the lower piezoelectric ceramic ring 5 is connected to the water pressure channel of the preamplifier circuit board 9. When the upper piezoelectric ceramic ring 2 and the lower piezoelectric ceramic ring 5 sense the water pressure signal, they are respectively Figure 2 Schematic diagram of the sound channel piezoelectric ceramic ring sensor device according to the embodiment of the present invention. After being respectively conditioned by the sound and water pressure channel signals of the preamplifier circuit board 9, they are converted into voltage signals for output.

[0046] Figure 2 Schematic diagram of the sound channel piezoelectric ceramic ring sensor device according to the embodiment of the present invention. The sound channel piezoelectric ceramic ring sensor device is the upper piezoelectric ceramic ring in the above-mentioned embodiment. As Figure 2 shown, the sound channel uses a receiving type P-51 piezoelectric material and a circular ring structure with dimensions of Φ40XΦ34X15 as the sensitive receiving element to design the sound sensor.

[0047] The P-51 piezoelectric ceramic material meets the following technical requirements;

[0048] Piezoelectric strain constant d 31 ≥186×10 -12 m / V;

[0049] Dielectric constant

[0050] Piezoelectric coupling coefficient K 31 ≥0.36;

[0051] Elastic compliance constant

[0052] Piezoelectric ceramic density value ρ≥7.6×10 3 kg / m 3

[0053] (1) Radial resonance frequency

[0054]

[0055] (2) Received sound pressure sensitivity

[0056] The acoustic sensor operates from 16 Hz to 8 kHz. Its upper limit frequency is far from the radial resonance frequency of 24148 Hz. After model calculation, the frequency response of its received sound pressure sensitivity has become flat. Its received sound pressure sensitivity in this frequency band can be calculated by the following formula:

[0057]

[0058] That is, SML (acoustic sensor)=-195.1 dB (0 dB = 1 V / μPa)

[0059] (3) Static capacitance

[0060]

[0061] (4) Output impedance

[0062] The low-frequency output impedance of the acoustic transducer is mainly determined by the low-frequency capacitance C T , and its approximate value can be calculated by the following formula:

[0063]

[0064] Taking the lower limit of the operating frequency as 16 Hz, then there is

[0065]

[0066] Figure 3 is a schematic diagram of a piezoelectric ceramic ring sensitive device for a water pressure channel according to an embodiment of the present invention. The piezoelectric ceramic ring sensitive device for a water pressure channel is the lower piezoelectric ceramic ring in the above embodiment, as Figure 3 shown,

[0067] The hydrostatic pressure receiver operates at extremely low frequencies. To obtain a relatively low impedance output, a piezoelectric material of type PMgN-51 with a high dielectric constant and a toroidal structure with dimensions of Φ72XΦ67X27 is used as the sensitive receiving element to design the hydrostatic pressure sensor.

[0068] The parameters of the PMgN-51 type piezoelectric ceramic material are as follows:

[0069] d 31 ≥270×10 -12 C / N; K 31 ≥0.35

[0070] ρ = 7.6×10 3 kg / m 3

[0071] The performance parameters of the piezoelectric vibrator are calculated as follows:

[0072] (1) Radial resonance frequency f r

[0073] The operating characteristics of the hydrostatic pressure receiver are determined by the piezoelectric vibrator. The radial resonance frequency can be calculated using the classical formula. When the operating frequency band is far from the resonance frequency, the received frequency response is flat.

[0074]

[0075] (2) Low-frequency capacitance C T

[0076]

[0077] (3) Output impedance Z

[0078] The low-frequency output impedance of the hydrostatic pressure receiver is mainly determined by the low-frequency capacitance C T , and can be approximately calculated according to the formula :

[0079]

[0080] When the lower limit of the operating frequency is taken as 0.1 Hz, then

[0081]

[0082] (4) Low-frequency hydrostatic pressure receiving sensitivity

[0083] When the hydrostatic pressure sensor operates in the frequency band of 0.1 Hz to 0.25 Hz, its upper limit frequency is already far from the radial resonance frequency of 12315 Hz. Based on the receiving model of the piezoelectric transducer, the sound pressure receiving sensitivity response is flat at the low-frequency end far from the resonance frequency.

[0084] The received sound pressure sensitivity is estimated according to the formula and M = 302.9 (μV / Pa) can be obtained, that is, the open-circuit hydrostatic pressure receiving sensitivity level SML = -190.4 dB (0 dB = 1 V / μPa).

[0085] Figure 4 is the schematic diagram of the sound pressure channel circuit according to the embodiment of the present invention,[ Figure 5 is the schematic diagram of the hydrostatic pressure channel circuit according to the embodiment of the present invention. As Figure 4 and Figure 5 shown, the sound and hydrostatic pressure channel circuits respectively adopt the integral feedback type high input impedance amplifier structure with the same structure, and different matching impedance values are adopted according to the different output impedances of the sound and hydrostatic pressure sensitive elements. According to Thevenin's theorem, considering the integrity of signal acquisition, the input impedance of the circuit should reach more than 20 times the internal resistance of the sensor. From the low-frequency output impedance of 880 kΩ of the piezoelectric sensitive element in the front sound channel, it can be known that the input impedance of the matching circuit should reach more than 10 times, that is, more than 8.8 MΩ; from the low-frequency output impedance of 22 MΩ of the piezoelectric sensitive element in the hydrostatic pressure channel, it can be known that the input impedance of the matching circuit should reach more than 10 times, that is, more than 220 MΩ.[

[0086] 1) The sound channel as Figure 4 shown: The pin 1 of the sound channel sensitive device is grounded, and the pin 2 enters the forward amplifier composed of operational amplifier U3A, resistor R11, resistor R10, capacitor C3, resistor R9, etc. after impedance matching through the matching resistor R12: Among them, R12 takes a resistance value of more than 8.8 MΩ, and the nominal value is selected as 9.1 MΩ; in order to balance the positive and negative input terminals (pins 3 and 2) of the operational amplifier U3A, R10 is also taken as 9.1 MΩ, and the capacitance value of the capacitor C3 is taken as a value close to the static capacitance of 11315 pF of the sound sensitive device, and the nominal value is taken as 11 nF.[

[0087] The gain of the forward amplifier is determined by the resistance values of resistors R9 and R11:[

[0088] Gain Au = 1 + R11 / R9

[0089] The sound signal output terminal of the forward amplifier passes through the integrator composed of resistor R15, capacitor C4, resistor R16, and operational amplifier U4B, and then after being limited by resistor R14, it is input to one end of the matching resistor R12 to form a bootstrap circuit, which improves the potential of the lower end of the matching resistor R12, thereby equivalently increasing the input impedance of the positive input terminal of the amplifier, that is, the equivalent input impedance is greater than the resistance value of R12, which is 9.1 MΩ.[

[0090] After introducing integral feedback into the circuit, the frequency response of the entire loop also changes, and its frequency response is approximately a high-pass filter, and the low-end cut-off frequency is:[

[0091]

[0092] If R15 is taken as 1 MΩ and C4 is taken as 10 nF, then:

[0093]

[0094] 2) The water pressure channel as Figure 5 shown: The pin 1 of the water pressure channel sensor device is grounded, and the pin 2 enters the positive amplifier composed of operational amplifier U1A, resistor R1, resistor R2, capacitor C1, resistor R39, etc. after impedance matching through the matching resistor R4: where R4 is taken as a resistance value of more than 220 MΩ, and the nominal value is selected as 360 MΩ; in order to balance the positive and negative input pins 3 and 2 of the operational amplifier U1A, R2 is also taken as 360 MΩ, and the capacitance value of capacitor C3 is taken as a value close to the static capacitance of the acoustic sensor device, which is 73042 pF, and the nominal value is taken as 0.68 uF.

[0095] The gain of the positive amplifier is determined by the resistance values of resistors R1 and R3:

[0096] The gain Au = 1 + R3 / R1

[0097] The acoustic signal output terminal of the positive amplifier passes through an integrator composed of resistor R5, capacitor C2, resistor R8, and operational amplifier U4B, and then after current limiting through resistor R6, it is input to one end of the matching resistor R4 to form a bootstrap loop, which increases the potential at the lower end of the matching resistor R4, thereby equivalently increasing the input impedance of the positive input terminal of the amplifier, that is, the equivalent input impedance is greater than the resistance value of R4, which is 360 MΩ.

[0098] After introducing integral feedback into the circuit, the frequency response of the entire loop also changes, and its frequency response is approximately a high-pass filter, and the low-end cut-off frequency is:

[0099]

[0100] If R5 is taken as 10 MΩ and C4 is taken as 0.16 uF, then:

[0101]

[0102] Thus, the signal conditioning circuit also differs in the cut-off frequency.

[0103] In summary, the embodiment of the present invention provides an integrated receiving device for sound pressure and water pressure signals. In order to reduce the interference between the sound and water pressure sensors when they are separately installed, reduce the influence of the baffle effect of the instrument cabin of the underwater installation platform on the directivity of the sound sensor, and reduce the installation hole seats and watertight joints, the piezoelectric ceramic sensitive elements of the sound and water pressure sensors are decoupled and vibration-isolated through vibration damping gaskets, and then vulcanized and sealed as a whole to the support substrate to form an integrated structure; a signal conditioning circuit board is installed in the cavity of the metal base of the support substrate to form a mechatronic structure, reducing signal transmission line losses and shielding electromagnetic interference; the signal conditioning circuit simultaneously completes the impedance matching and frequency division processing of the high output impedance of the sound and water pressure sensitive elements through an integral feedback loop, and outputs the sound and water pressure signals to the subsequent stage respectively.

[0104] The above specific embodiments only describe the design principle of the present invention. The shapes and names of the components in this description can be different and are not limited. Therefore, those skilled in the art of the present invention can modify or equivalently replace the technical solutions recorded in the foregoing embodiments; and these modifications and replacements do not depart from the purpose and technical solutions of the present invention, and shall fall within the protection scope of the present invention.

Claims

1. An integrated receiving device for sound pressure and water pressure signals, characterized in that, Including: The upper piezoelectric ceramic ring of the sound pressure sensor, the lower piezoelectric ceramic ring of the water pressure sensor, and the support body; The upper piezoelectric ceramic ring and the lower piezoelectric ceramic ring are stacked on the support body, one above the other; The upper piezoelectric ceramic ring and the lower piezoelectric ceramic ring are potted on the support body to form an integral structure with the support body.

2. The device according to claim 1, characterized in that, Among them, A latex gasket is provided between the upper piezoelectric ceramic ring and the lower piezoelectric ceramic ring.

3. The device according to claim 1, characterized in that, Among them, The support body includes: an upper cover plate, a lower cover plate, and a base; The upper cover plate, the lower cover plate, and the base are all provided with annular grooves. The upper piezoelectric ceramic ring is disposed between the annular grooves of the upper cover plate and the annular grooves of the lower cover plate, and the lower piezoelectric ceramic ring is disposed between the annular grooves of the lower cover plate and the base.

4. The device according to claim 2 or 3, characterized in that, Among them, The annular grooves are filled with polyurethane or latex gaskets.

5. The device according to claim 3, characterized in that, Among them, The upper cover plate is connected to the lower cover plate, and the lower cover plate is connected to the base by screws.

6. The device according to claim 3, characterized in that, Among them, The base is a hollow cavity structure, and a signal conditioning circuit board is disposed in the cavity of the base. The signal conditioning circuit board is used for conditioning the sound pressure signal and the water pressure signal.

7. The device according to claim 3, characterized in that, Among them, The support body further includes a rear cover plate, and the rear cover plate is connected to the base by screws.

8. The device according to claim 3, characterized in that, Among them, The material of the base is metal.

9. The device according to claim 1, characterized in that, Also including: An upper wire and a lower wire, The upper wire is used to lead out the positive and negative poles of the upper piezoelectric ceramic ring, and the lower wire is used to lead out the positive and negative poles of the lower piezoelectric ceramic ring.

10. The device according to claim 9, characterized in that, Among them, The negative poles of the upper piezoelectric ceramic ring and the lower piezoelectric ceramic ring are connected to the base in common ground; The positive poles of the upper piezoelectric ceramic ring and the lower piezoelectric ceramic ring are connected to the dual-channel input ends of the signal conditioning circuit board.

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