CN104375134A - Universal underwater acoustic measurement system - Google Patents

Abstract

The invention discloses a universal underwater acoustic measurement system which mainly comprises a transmitting transducer group, a transmitting extension, a receiving extension and a display control extension, wherein the display control extension is respectively connected with the transmitting extension and the receiving extension, the transmitting extension is connected with the transmitting transducer group and used for driving the transmitting transducer group, the transmitting transducer group is used for completing underwater transmission of acoustic signals in a working frequency band, the transmitting extension is used for completing underwater acoustic measurement signal generation and driving the transmitting transducer group, the receiving extension is used for completing receiving, conditioning, collecting and storing of the underwater acoustic signals, and the display control extension completes parameter setting, transmitting and receiving control, state monitoring, received waveform display and target intensity calculation. The system has strong universality and high cost performance, is favorable for portable use, has modular design, and can be independently used by each subsystem.

Description

Universal underwater acoustic measurement system

technical field

The invention relates to the technical field of acoustics, in particular to a general measurement system for underwater acoustics.

Background technique

The existing underwater acoustic measuring instruments in China can be divided into two categories: noise measuring instruments and echo measuring instruments, both of which belong to the exclusive measuring frequency band, and cannot be reused in terms of hardware and software resources, which brings waste of cost to users. At the same time, the special use of measurement frequency bands and the dispersion of functions have brought inconvenience to users.

Contents of the invention

Aiming at the technical problems in the above-mentioned prior art, the present invention provides a general underwater acoustic measurement system for measuring the target strength of an underwater target to be measured and capable of function expansion. The universal underwater acoustic measurement system of the present invention has strong versatility, high cost performance, is convenient for portable use, and has a modular design, so that each sub-system can be used independently.

In order to achieve the above object, the technical scheme that the present invention takes is as follows:

A general underwater acoustic measurement system, mainly composed of a transmitting transducer group, a transmitting extension, a receiving extension and a display control extension, the display control extension is respectively connected to the transmitting extension and the receiving extension, and the transmitting extension is connected to the The transmitting transducer group is used to drive the transmitting transducer group. The transmitting transducer group mainly completes the underwater transmission of the acoustic signal in the working frequency band, and the transmitting extension mainly completes the generation and driving of the underwater acoustic measurement signal. The transmitting transducer group, the receiving sub-unit mainly completes the reception, conditioning, acquisition and storage of underwater acoustic signals, and the display control sub-unit completes parameter setting, transmission and reception control, status monitoring, received waveform display and target strength calculation.

The transmitting extension, receiving extension and display control extension are integrated in an industrial computer including a main control board, a signal conditioning board, an A/D acquisition board and a D/A conversion board.

The transmitting extension, receiving extension and display control extension are integrated into an industrial computer including a main control board, a signal conditioning board, and an A/D acquisition board, and an industrial computer including a main control board and a D/A conversion board.

The transmitting transducer group includes 3 sets of transducers to complete signal transmission within the frequency band of 1kHz-60kHz.

The three groups of transducers are:

Transducer 1: a curved disc transducer, which completes signal transmission in the frequency band of 1kHz to 3kHz;

Transducer 2: an inlaid ring transducer with a baffle, which completes signal transmission within the frequency band of 3kHz to 10kHz;

Transducer 3: Inlaid ring transducer with baffle + circular tube transducer with baffle + longitudinal oscillator transducer with matching layer to complete signal transmission in the 10kHz-60kHz frequency band.

The transmitting extension is mainly composed of a signal source, a digital-to-analog conversion device, a power amplifier, and a matching network.

The receiving extension is mainly composed of signal conditioning equipment, signal acquisition equipment, and signal storage equipment.

The signal conditioning equipment is composed of a low-noise pre-amplification circuit, a filter circuit, and a post-amplification circuit. The pre-amplification circuit is a low-noise instrument amplifier with adjustable magnification. The filter circuit adopts a low-pass plus high-pass Formal design, the filtered amplifier circuit can flexibly adjust the gain of the whole circuit.

The display control extension includes a transmitting extension interface for completing signal source related parameter setting, power amplifier working state control, parameter control, working state monitoring, and channel gating of the matching network, and for completing signal source receiving signal monitoring, Parameter setting of signal conditioning equipment, channel gating, and receiving extension interface that can give target strength calculation results

The general underwater acoustic measurement system provided by the present invention has a main function of measuring the target strength of an underwater target, and can expand the function to perform general underwater acoustic measurement. It is capable of transmitting underwater active detection signals and receiving underwater acoustic signals. Strong versatility, easy to carry, and modular design, each subsystem can be used independently.

This system adopts common shelf-type products on the market to complete the signal processing and display control tasks of this system, adopts full-band receiving transducers to solve the problem of common frequency bands, adopts portable design for user convenience, and adopts modular and combined design , to realize the split and combined use of the system. The specific manifestation is as follows:

●High versatility:

1) Universal function: it can measure both the noise of the target and the echo of the target;

2) Common frequency band: the frequency band is 1kHz ~ 60kHz, covering almost all frequency bands in the commonly used underwater acoustic measurement field;

●High cost performance:

While ensuring product performance and measurement accuracy, the following design methods are used to reduce production costs:

1) The hydrophones and processors are produced with shelf-type products, which are easy to maintain and reduce production costs;

2) The transducer base array adopts the integrated design of frequency bands, which saves production materials and reduces production costs;

●Easy to carry:

The system is divided into host, base array and hydrophone, which are placed in three boxes with wheels, which is very convenient for transportation and portability.

●Modular design:

The system adopts a modular design, and each device can be used independently.

Description of drawings

Fig. 1 is a system composition block diagram provided by the present invention;

Fig. 2 is a topological structure diagram of the first embodiment of the system of the present invention;

Fig. 3 is a topological structure diagram of the second embodiment of the system of the present invention;

Fig. 4 is the actual measurement diagram of the pointing characteristics of an embodiment of the mosaic ring transducer with a baffle;

Fig. 5 is the display control interface of the transmitting extension;

Figure 6 is the display control interface of the receiving extension.

Detailed ways

The technical solution of the present invention will be described in detail below in conjunction with the accompanying drawings and specific embodiments.

As shown in Figure 1, the general underwater acoustic measurement system provided by the present invention is mainly composed of a transmitting transducer group, a transmitting extension, a receiving extension and a display control extension. The composition and functions of each part are as follows:

Transmitting transducer group: It consists of 3 sets of transducers, which mainly complete the underwater transmission of acoustic signals in the working frequency band;

Transducer 1: a curved disc transducer, which completes signal transmission in the frequency band of 1kHz to 3kHz;

Transducer 2: an inlaid ring transducer with a baffle, which completes signal transmission within the frequency band of 3kHz to 10kHz;

Transducer 3: Inlaid ring transducer with baffle + circular tube transducer with baffle + longitudinal oscillator transducer with matching layer to complete signal transmission in the 10kHz-60kHz frequency band.

Transmitting extension: The transmitting extension is composed of signal source, digital-to-analog conversion equipment, power amplifier, and matching network. It mainly completes the functions of generating underwater acoustic measurement signals and driving the transmitting transducer group. Among them:

Signal source: generate the required acoustic measurement signal according to the test plan;

Digital-to-analog conversion equipment: convert the digital signal generated by the signal source into an analog signal, and amplify it as the input signal of the power amplifier;

Power amplifier: amplifies the power of the signal generated by the signal source, drives the transmitting transducer group through the matching network, and completes the transmission of the measurement signal;

Matching network: perform impedance matching between the power amplifier and the transducer group to ensure the electroacoustic conversion efficiency.

Receiving extension: The receiving extension is composed of signal conditioning equipment, signal acquisition equipment, and signal storage equipment. It mainly completes the functions of receiving, conditioning, collecting and storing underwater acoustic signals.

Signal conditioning equipment: complete the amplification and filtering function of the signal received by the 8105 standard hydrophone;

Signal acquisition equipment: complete the A/D sampling function of analog signals;

Signal storage device: complete the storage function of digital signals.

Display control extension: complete parameter setting, transmission and reception control, status monitoring, reception waveform display, target strength calculation and other functions.

The topology diagram of the general underwater acoustic measurement system is shown in Fig. 2 and Fig. 3. 2 shows the configuration of the first embodiment, and FIG. 3 shows the configuration of the second embodiment.

In Embodiment 1, the transmitting transducer group includes: 3 sets of transmitting transducers; one industrial computer, including: 1 main control board, 2 signal conditioning boards, 1 A/D acquisition board, and D/A conversion 1 board; 1 power amplifier; 1 system power supply.

In the second embodiment, the transmitting transducer group includes: 3 sets of transmitting transducers; two industrial computers, and the industrial computer 1 includes: 1 main control board, 2 signal conditioning boards, 1 A/D acquisition board; Machine 2 includes: 1 main control board, 1 D/A conversion board; 1 power amplifier; 1 system power supply.

Below is the detailed technical design scheme of each extension of the system of the present invention:

Transmitting transducer set:

The underwater transmitting transducer is a functional module of the general underwater acoustic measurement system, mainly for underwater transmitting of acoustic signals. When in use, a certain voltage excitation is applied to the underwater transmitting transducer at a certain frequency or frequency band through a power amplifier and other equipment to realize the conversion from an electrical signal to an acoustic signal and generate an acoustic signal of a given form and intensity. Water spreads outward.

The working principle of the underwater transmitting transducer is that the voltage signal output by the signal source is modulated by the equalization circuit and input to the power amplifier. The output electrical signal of the power amplifier drives the transducer after passing through the matching circuit, and the transducer converts the input electrical signal It is specially converted into a mechanical vibration signal, so as to radiate the acoustic signal to the water, and complete the conversion of the electrical signal to the underwater acoustic signal. The matching and equalizing circuit changes the frequency response characteristics of the transducer, so that the transmission voltage response fluctuation in the working frequency band is reduced to within the index requirement, and a certain electro-acoustic conversion efficiency is guaranteed.

The underwater transmitting transducer group includes 3 sets of transducers, and the working frequency range covers 1-60kHz. Among them, the transducer 1 is a curved disc transducer, which completes the signal transmission in the 1kHz-3kHz frequency band; the transducer 2 is a mosaic circular ring transducer with a baffle, and completes the signal transmission in the 3kHz-10kHz frequency band; Transducer 3 is an inlaid ring transducer with a baffle + a circular tube transducer with a baffle + a longitudinal oscillator transducer with a matching layer to complete signal transmission in the 10kHz-60kHz frequency band.

(1) 1kHz～3kHz frequency band transducer

The transducer in this frequency band adopts the curved disk transducer component transducer, which has low frequency, small size, light weight, and relatively wide bandwidth, and is very suitable for use as a lightweight sound source. This solution can achieve a sound source level of 195dB within the frequency range. Omnidirectional in the horizontal direction, directivity in the vertical direction is greater than 90°. Physical size≤Ф180mm×1000mm, weight≤25kg.

(2) 3kHz～10kHz low frequency transducer design scheme

This frequency band adopts the mosaic ring transducer form with a baffle. This type of transducer is small in size, high in efficiency, high in power and light in weight. The transducer parameters in the embodiment of the present invention are as follows in Table 1:

Table 1

After the baffle is added, the horizontal directivity can be better formed. Figure 4 is a measured diagram of the pointing characteristic of an embodiment of the baffle transducer. The higher the frequency, the better the pointing characteristic.

3kHz horizontal directivity: main lobe width 93.8°, back radiation -12dB;

6kHz horizontal directivity: main lobe width 68.7°, back radiation -18dB;

10kHz horizontal directivity: main lobe width 71.3°, back radiation -22dB.

(3) 10kHz～20kHz transducer

The transducer in this frequency band adopts a circular tube transducer with a baffle. The circular tube transducer is the most common type of underwater acoustic transducer. It has a simple structure and high efficiency. It is omnidirectional in the horizontal direction. , You can also use the anti-acoustic baffle for directional transceiver. The transducer parameters in the embodiment of the present invention are as follows in Table 2:

Table 2

(4) 20kHz～40kHz transducer

The transducer in this frequency band also adopts a circular tube transducer with a baffle. The transducer parameters of different specifications are shown in Table 3:

table 3

(5) 40kHz～60kHz transducer

The transducer in this frequency band is implemented by a longitudinal oscillator transducer with a matching layer. This type of transducer has a simple structure, convenient processing, high efficiency, and high power. After adding a matching layer, the bandwidth is further expanded. It is currently used as a strong The power sound source is widely used in underwater acoustic and ultrasonic engineering, and its operating frequency is generally around tens of kHz. The transducer parameters of different specifications are shown in Table 4:

Table 4

Transmitting extension:

The transmitting extension is composed of signal source, digital-to-analog conversion equipment, power amplifier, and matching network. It mainly completes the functions of generating underwater acoustic measurement signals and driving the transmitting transducer group.

(1) Signal source

The function of the signal source is to generate the required acoustic measurement signals according to the test protocol. According to the test requirements of this project, the signal generated by the signal source is mainly realized through programming, and can also be entered into a data file. The user can control the parameters of the signal source through the display and control interface. The main parameters of the signal source are as follows:

Signal form: CW pulse;

Pulse width: can be set;

Launch cycle: can be set;

Center frequency: 1KHz, 5KHz, 10KHz, 20KHz, 30KHz, 60KHz, others (can be set manually within the working frequency band).

(2) Digital to analog conversion equipment:

It is mainly used to convert the digital signal generated by the signal source into an analog signal and amplify it as the input signal of the power amplifier.

(3) Power amplifier:

The main function is to amplify the power of the signal generated by the signal source, drive the transmitting transducer group through the matching network, and complete the transmission of the measurement signal.

The transmitting circuit of the power amplifier is composed of a power amplifier power supply and a power amplifier module. The power amplifier part is powered by AC220V, and the power supply module is used to convert the power required by the amplifier module. The user selects the frequency, form and size of the signal to be transmitted on the display and control interface, and the corresponding waveform is generated by the signal source, and output to the power amplifier module through the analog-to-digital conversion device. The user can monitor the working status of the power amplifier and control the output power on the display and control interface.

In the embodiment of the present invention, according to the emission sound source level requirements of different emission transducers, the main parameters of the power amplifier are determined as follows:

Power supply: AC power supply: AC220V;

Working frequency range: 20Hz～60kHz;

Output a) Continuous transmission power (under the condition of good heat dissipation): ≥2000W;

b) Dynamic range: ≥60dB; SNR: ≥66dB;

c) Power amplifier efficiency: ≥90%;

d) Distortion ≤ 1%;

Reliability, maintainability, testability, safety requirements

a) Signal input and output are electrically isolated from peripheral equipment;

b) With short-circuit, over-current and over-heat protection and automatic reset function;

c) There are power indicator light and working status indicator light;

d) There are obvious safety signs on all high-voltage dangerous parts;

(4) Matching network:

The main function is to perform impedance matching between the power amplifier and the transducer group to ensure the electroacoustic conversion efficiency. The matching network is composed of a power switch and a power amplifier matching network.

On the display and control interface, the power switch can be controlled by the main control board, and the corresponding matching network can be selected to open, so that the signal output by the power amplifier module can be added to the corresponding transducer.

In the embodiment of the present invention, its main parameters are: matching network efficiency: average ≥ 80%.

Receive extension:

The receiving extension is composed of signal conditioning equipment, signal acquisition equipment, and signal storage equipment. It mainly completes the functions of receiving, conditioning, collecting and storing underwater acoustic signals.

(1) Signal conditioning equipment

It mainly completes the frequency band amplification and filtering function of the 8105 standard hydrophone receiving signal. Its main working principle is that the signal conditioning equipment receives the signal of the hydrophone 8105, amplifies, filters, and amplifies again, and then collects it by the signal acquisition equipment.

The signal conditioning equipment is composed of a low-noise pre-amplification circuit, a filter circuit, and a post-amplification circuit. In order to reduce circuit noise, the pre-amplification circuit adopts a low-noise instrumentation amplifier with adjustable magnification, and the filter part is designed in the form of low-pass plus high-pass. The filtered amplifying circuit can flexibly adjust the gain of the entire circuit. The user can select the filter channel through the display and control software.

The signal conditioning equipment is mainly realized by boards. In this embodiment, its main parameters are as follows:

Gain: 20dB, 40dB, 60dB (adjustable);

Working bandwidth: 1k～3kHz, 3k～10kHz, 10k～20kHz, 20k～40kHz, 40k～60kHz;

Channel noise: <5uV;

Number of channels: 2.

(2) Signal acquisition equipment

It mainly completes the A/D sampling function of the analog signal output by the signal conditioning equipment. Use the relatively mature 16bit, multi-channel A/D board on the market to realize. In this embodiment, its main parameters are as follows:

AD collection resolution: 16bit;

Sampling frequency: 240kHz;

Channel noise: <5uV;

Number of channels: 2.

(3) Signal storage device

It mainly completes the storage function of digital signals. Use the hard disk of the industrial computer to realize it through the programming of the display control software. And can complete the playback function of stored data.

Show controlling extension:

Complete parameter setting, transmission and reception control, status monitoring, reception waveform display, target strength calculation and other functions. The reference interface is shown in Figure 5 and Figure 6.

(1) Transmitting extension interface

Through this interface, the user can complete signal source related parameter setting, power amplifier working state control, parameter control, and working state monitoring, and can perform channel gating of the matching network.

(2) Receive extension interface

Through this interface, the user can monitor the received signal of the hydrophone, set the parameters of the signal conditioning equipment, select the channel, and give the calculation result of the target strength.

The above-mentioned embodiments are only used to illustrate the present invention, but are not used to limit the protection scope of the claims. All equivalent transformations and improvements made on the basis of the technical solution of the present invention shall not be excluded from the protection scope of the present invention.

Claims (9)

1. a general underwater sound measuring system, it is characterized in that, primarily of transmitting transducer group, launch extension set, receive extension set and display and control extension set composition, described display and control extension set connects described transmitting extension set respectively and receives extension set, described transmitting extension set connects described transmitting transducer group, for driving described transmitting transducer group, described transmitting transducer group is for the underwater emission of acoustic signal in frequency band of finishing the work, described transmitting extension set has been used for underwater sound measuring-signal and has generated and drive transmitting transducer group, described reception extension set is for completing the reception of underwater sound signal, conditioning, gather and store, described display and control extension set has been used for optimum configurations, launch and accept controls, condition monitoring, receive waveform display and target strength calculating.

2. general underwater sound measuring system according to claim 1, is characterized in that, described transmitting extension set, reception extension set and display and control extension set are integrated in an industrial computer comprising master control borad, signal regulating panel, A/D collection plate and D/A change-over panel.

3. general underwater sound measuring system according to claim 1, it is characterized in that, described transmitting extension set, receive extension set and display and control extension set and be integrated in that one comprises master control borad, signal regulating panel, the industrial computer of A/D collection plate and one comprises in the industrial computer of master control borad, D/A change-over panel.

4. general underwater sound measuring system according to claim 1, is characterized in that, described transmitting transducer group comprises 3 cover transducers, and the signal completed in 1kHz ~ 60kHz frequency band is launched.

5. general underwater sound measuring system according to claim 4, is characterized in that, described 3 groups of transducers respectively:

Transducer 1: adopt bending disk transducer, the signal completed in 1kHz ~ 3kHz frequency band is launched;

Transducer 2: adopt the edge of band baffle to spell annulus transducer, the signal completed in 3kHz ~ 10kHz frequency band is launched;

Transducer 3: adopt the edge of band baffle to spell the vertical resonator transducer of the pipe transducer+employing band matching layer of annulus transducer+employing band baffle, the signal completed in 10kHz ~ 60kHz frequency band is launched.

6. general underwater sound measuring system according to claim 1, is characterized in that, described transmitting extension set is primarily of signal source, digital-to-analogue conversion equipment, power amplifier, matching network composition.

7. general underwater sound measuring system according to claim 1, is characterized in that, described reception extension set is primarily of signal condition equipment, signal collecting device, signal storage equipment composition.

8. general underwater sound measuring system according to claim 7, it is characterized in that, described signal condition equipment adopts low noise pre-amplification circuit, filtering circuit, rearmounted amplifying circuit and composition, described pre-amplification circuit adopts low noise instrument amplifier, enlargement factor is adjustable, described filtering circuit adopts low pass to add the form design of high pass, and filtered amplifying circuit can the gain of the whole circuit of flexible.

9. general underwater sound measuring system according to claim 1, it is characterized in that, described display and control extension set comprises for settling signal source relative parameters setting, power amplifier working state control, state modulator, Working Status Monitoring, carries out the transmitting extension set interface of the passage gating of matching network, and for the monitoring of settling signal source Received signal strength, the optimum configurations of signal condition equipment, passage gating, and provide the reception extension set interface of target strength result of calculation.