CN106546991A - The device and method of audible target aerial reconnaissance under water - Google Patents

Abstract

The present invention relates to a device and method for aerial detection of underwater sound-emitting targets. The device includes: an underwater sound generation unit, a laser interference detection unit, and a data acquisition and processing unit; the underwater sound generation unit includes a signal generator and an underwater sound wave An exciter; the laser interference detection unit includes a laser, a modulation optical path, an interference optical path, and a photodetector. The aerial detection device and method for underwater sound-emitting targets of the present invention can realize the feature recognition and extraction of underwater targets through the detection of weak water surface acoustic waves. The on-board telemetry system realizes the laser interferometric detection technology, which can not only realize high-efficiency, large-area search, but also break through the limitation of detection depth.

Description

Device and method for aerial detection of underwater sound-emitting targets

technical field

The invention relates to the technical field of laser remote sensing detection, in particular to an aerial detection device and method for an underwater sound-emitting target.

Background technique

Whether in the military or civilian fields, the feature extraction and recognition of underwater targets has a wide range of needs. Especially in the military field, the detection of underwater military targets such as submarines is the key to victory in sea battles. How to achieve accurate, fast and effective anti-submarine detection has become a major issue at present.

At present, shipborne sonar is still the mainstream means of underwater target detection, but due to the poor maneuverability, flexibility and concealment of ships at sea, the application of shipborne sonar in underwater target detection has been limited. In addition, airborne blue-green lidar detection technology is also one of the research hotspots this year. It is an active, large-area and high-speed ocean detection method. It has already shown certain competitiveness in shallow water detection. However, because the transmission loss of blue-green laser in seawater is greater than that of sound transmission, the detection depth is limited.

To sum up, one of the existing technical problems to be solved urgently is: how to develop a new and efficient aerial telemetry technology for underwater sound targets based on the current status of underwater target detection technology to meet the needs of modern coastal defense.

Contents of the invention

In order to solve the above-mentioned technical problems, the present invention proposes an underwater sound-emitting target aerial detection device on the one hand, including: an underwater sound generation unit, a laser interference detection unit, and a data acquisition and processing unit;

The underwater acoustic generating unit includes a signal generator and an underwater acoustic exciter;

The signal generator is used to generate a driving signal of a preset frequency for driving the underwater acoustic wave exciter;

The underwater acoustic wave exciter is used to generate surface micro-amplitude waves with the same frequency as the acoustic signal of the sounding target on the water surface of the target water area according to the driving signal;

The laser interference detection unit includes a laser, a modulation optical path, an interference optical path, and a photodetector;

The laser is used to emit a laser beam with a preset wavelength;

The modulation optical path is used to expand and split the laser beam, and reflect the split laser beam to the water surface;

The interference optical path is used to integrate the measurement beam reflected by the water surface and the reference beam into a coaxial axis, and make the measurement beam and the reference beam interfere;

The photodetector is used to receive the light intensity signal of the interference light;

The data collection and processing unit is used for collecting and processing the light intensity signal, so as to judge and evaluate the characteristics of the sounding target according to the processing result.

Optionally, the underwater sound generating unit also includes a power amplifier;

The power amplifier is used to amplify the power of the drive signal with a preset frequency generated by the signal generator.

Optionally, the data acquisition and processing unit includes a data acquisition card and a central processing and analysis module;

The data acquisition card is used to collect and buffer the voltage signal of the light intensity signal;

The central processing and analysis module is used to perform signal processing and analysis on the voltage signal correspondingly in the time domain and frequency domain, and display the analysis results.

Optionally, the data acquisition card adopts a sampling frequency of up to 1.25 MHz and an acquisition accuracy of 16 bits.

Optionally, the central processing and analysis module includes an oscilloscope and a computer.

Optionally, the modulation optical path includes a laser beam expander, a beam splitter and a first reflector;

The laser beam emitted by the laser is first expanded by the laser beam expander, and then divided into two beams by the beam splitter, one of which is used as a reference beam, and the other beam is reflected by the first beam After reflection by the mirror, it is irradiated onto the water surface as the measurement beam.

Optionally, the interference optical path includes a second reflector, an attenuator, and a narrow-band interference filter;

The reference beam is reflected by the second mirror, passes through the attenuator, and interferes with the measurement beam scattered back from the water surface to obtain an interference beam, so that the interference beam passes through the narrow-band interference filter After the light sheet, illuminate the detection window of the photodetector.

Optionally, the interference optical path also includes an adjustable diaphragm;

The adjustable aperture is used to adjust the size of the light spot of the interference beam.

Optionally, the underwater sound wave exciter includes an underwater speaker.

On the other hand, the present invention also provides a method for aerial detection of underwater sound-emitting targets based on any of the above-mentioned devices, including:

The signal generator generates a drive signal of a preset frequency for driving the underwater acoustic wave exciter;

The underwater acoustic wave exciter generates surface micro-amplitude waves with the same frequency as the acoustic signal of the sounding target on the water surface of the target water area according to the driving signal;

The laser emits a laser beam with a predetermined wavelength;

The modulation optical path expands and splits the laser beam, and reflects the split laser beam to the water surface;

The interference optical path integrates the measurement beam reflected by the water surface and the reference beam into a coaxial axis, and causes the measurement beam and the reference beam to interfere;

The photodetector receives the light intensity signal of the interference light;

The data collection and processing unit collects and processes the light intensity signal, so as to judge and evaluate the characteristics of the sounding target according to the processing result.

The aerial detection device and method for underwater sound-emitting targets of the present invention can realize the feature recognition and extraction of underwater targets through the detection of weak water surface acoustic waves. The on-board telemetry system realizes the laser interferometric detection technology, which can not only realize high-efficiency, large-area search, but also break through the limitation of detection depth.

Description of drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following will briefly introduce the drawings that need to be used in the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description are For some embodiments of the present invention, those skilled in the art can also obtain other drawings based on these drawings without creative work.

Fig. 1 is a structural schematic diagram of an underwater acoustic target aerial detection device according to an embodiment of the present invention;

Fig. 2 is a schematic flowchart of an aerial detection method for an underwater sound-emitting target according to an embodiment of the present invention.

detailed description

In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly described below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are the Some, but not all, embodiments are invented. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the protection scope of the present invention.

Fig. 1 is a schematic structural diagram of an underwater sound-emitting target aerial detection device according to an embodiment of the present invention. As shown in Fig. 1 , the device includes: an underwater sound generation unit 100, a laser interference detection unit 200, and a data acquisition and processing unit 300;

Specifically, the underwater sound generation unit 100 includes a signal generator 110 and an underwater sound wave exciter, optionally, the underwater sound wave exciter includes an underwater speaker 130;

The signal generator 110 is used to generate a driving signal of a preset frequency for driving the underwater acoustic wave exciter 130;

The underwater acoustic wave exciter 130 is used to generate surface micro-amplitude waves with the same frequency as the acoustic signal of the sounding target on the water surface of the target water area according to the driving signal;

Further, the laser interference detection unit 200 includes a laser 210, a modulation optical path, an interference optical path, and a photodetector 290;

The laser 210 is used to emit a laser beam with a predetermined wavelength. It can be understood that the laser beam needs to have certain monochromaticity and stability to meet detection requirements.

Preferably, the laser 210 may be a single-frequency solid-state laser, which outputs linearly polarized light with a narrow linewidth and a wavelength of 532nm;

The modulation optical path is used to expand and split the laser beam, and reflect the split laser beam to the water surface;

The interference optical path is used to integrate the measurement beam reflected by the water surface and the reference beam into a coaxial axis, and make the measurement beam and the reference beam interfere;

The photodetector 290 is used to receive the light intensity signal of the interference light;

The data collection and processing unit 300 is used for collecting and processing the light intensity signal, so as to judge and evaluate the characteristics of the sounding target according to the processing result.

The aerial detection device for underwater sound-emitting targets in this embodiment can realize the feature recognition and extraction of underwater targets through the detection of weak water surface acoustic waves. It has the advantages of non-contact and high precision, and can be combined with space-borne or airborne The telemetry system implements the laser interferometric detection technology, which can not only realize efficient and large-area search, but also break through the limitation of detection depth.

Further, as a preference of the above embodiment, the underwater acoustic generating unit 100 may also include a power amplifier 120;

The power amplifier 120 is used to amplify the power of the driving signal with a preset frequency generated by the signal generator 110 .

As a preference of this embodiment, the signal generator 110 can be connected to the power amplifier 120 through a high-quality BNC-to-RCA cable. The signal generator 110 generates a sine wave signal with a preset frequency and outputs it to the power amplifier 120. The frequency and amplitude of the signal The value is adjustable;

The power amplifier 120 is connected to the 8-ohm constant resistance underwater speaker 130 through a dedicated audio signal line.

Further, as a preference of the above embodiment, the data acquisition and processing unit 300 may include a data acquisition card and a central processing and analysis module;

The data acquisition card is used to collect and buffer the voltage signal of the light intensity signal;

The central processing and analysis module is used to perform signal processing and analysis on the voltage signal correspondingly in the time domain and frequency domain, and display the analysis results.

Wherein, as a preference of this embodiment, the data acquisition card may adopt a sampling frequency of up to 1.25 MHz and an acquisition accuracy of 16 bits.

On this basis, the central processing analysis module may further include an oscilloscope 310 and a computer 320 .

Wherein, the computer 320 can be used to run preset signal acquisition and processing software.

Further, as a preference of the above embodiment, the modulation optical path may include a laser beam expander 220, a beam splitter 230 and a first reflector 240;

Specifically, the laser beam emitted by the laser 210 is first expanded by the laser beam expander 220, and then divided into two beams by the beam splitter 230, one of which is used as a reference beam, and the other is used as a reference beam. The laser beam is reflected by the first reflector 240 and irradiated onto the water surface as the measurement beam.

Further, as a preference of the above embodiment, the interference optical path may include a second mirror 250, an attenuator 260 and a narrow-band interference filter 280;

Wherein, the reference beam is reflected by the second mirror 250, passes through the attenuator 260, and interferes with the measurement beam scattered back from the water surface to obtain an interference beam, so that the interference beam passes through the After the narrow-band interference filter 280, it illuminates the detection window of the photodetector 290 (not shown in the figure).

Specifically, the reference beam is reflected by the second reflector 250 and then passes through the attenuator 260 to appropriately attenuate the light intensity of the reference beam so that it is consistent with the light intensity of the measurement beam scattered back from the water surface, so as to obtain a better effect. A good interference beam, the interference beam passes through the narrow-band interference filter 280 and irradiates the detection window of the photodetector.

It can be understood that the photodetector 290 needs to have a larger detection window to adapt to a larger beam cross section after beam expansion.

Since the measurement beam scattered back from the water surface is extremely weak, the intensity of the corresponding interference beam is also very weak, so the photodetector 290 needs to have a relatively high gain.

Further, as a preference of the above embodiment, the interference optical path may further include an adjustable diaphragm 270;

The adjustable diaphragm 270 is used to adjust the size of the light spot of the interference beam.

Specifically, the measurement light returned to the laser interference detection unit 200 interferes with the reference light on one side of the beam splitter 230, and passes through the adjustable diaphragm 270 and the optical filter 280 to adjust the spot and filter out the stray light, and finally the The photodetector 290 receives it.

On the basis of the above embodiments, the laser 210 can be a small semiconductor green solid-state laser with a wavelength of 532nm, ultra-narrow linewidth, good monochromaticity, and a coherence length of up to 100m;

Specifically, the output beam of the laser 210 first passes through the modulation optical path, and the beam is divided into two beams after passing through the beam expander 220 and the beam splitter 230 in turn, and the reference light passes through the second reflector 250, the attenuator 260, and the second reflector 250 in turn. , beam splitter 230 mirrors;

The measurement light passes through the first reflector 240, the water surface, the first reflector 240, and the beam splitter 230 in sequence; then passes through the interference optical path, and the reference light and measurement light that meet on the side of the beam splitter pass through the adjustable diaphragm 270, Optical filter 280 to obtain ideal interference light;

The obtained interference beam is irradiated on the window of the photodetector 290, and an appropriate amplification gain is set according to the power of the beam. The signal is converted from an optical signal to an electrical signal and output to the signal acquisition and processing unit 300. The connecting line is divided into two paths, One way is connected to the oscilloscope 310 through the BNC line, and the other way is connected to the data acquisition card of the data acquisition and processing computer through the BNC line.

Fig. 2 is a schematic flow chart of an aerial detection method for an underwater sound-emitting target according to an embodiment of the present invention. As shown in Fig. 2, the method includes:

A1: the signal generator generates a driving signal of a preset frequency for driving the underwater acoustic wave exciter;

A2: The underwater acoustic wave exciter generates surface micro-amplitude waves at the same frequency as the acoustic signal of the sounding target on the water surface of the target water area according to the driving signal;

A3: The laser emits a laser beam with a preset wavelength;

A4: The modulation optical path expands and splits the laser beam, and reflects the split laser beam to the water surface;

A5: The interference optical path integrates the measurement beam reflected by the water surface and the reference beam into a coaxial axis, and causes the measurement beam and the reference beam to interfere;

A6: the photodetector receives the light intensity signal of the interference light;

A7: The data collection and processing unit collects and processes the light intensity signal, so as to judge and evaluate the characteristics of the sounding target according to the processing result.

Specifically, the laser emits a beam of laser light, which is divided into measurement light and reference light by a beam splitter after being expanded by a beam expander. The light intensity of the reference light is adjusted by the attenuator; the function signal generator generates a preset The frequency driving signal drives the underwater speaker after passing through the power amplifier, and generates surface micro-amplitude waves with the same frequency as the acoustic signal on the water surface; the measurement light irradiated on the water surface is modulated by the micro-amplitude waves on the water surface, and part of it returns to the laser Interference detection unit; the measurement light returned to the laser interference detection unit interferes with the reference light on one side of the beam splitter, and passes through the adjustable diaphragm and filter to adjust the spot and filter out the stray light, and finally receives it by the photodetector ;The data acquisition card embedded in the data acquisition and processing computer reads the voltage signal output by the photoelectric detector and temporarily stores the data in the cache of the data acquisition card, and the computer controls the reading of the data in the cache through the unit host computer software; The obtained sound signal data is analyzed in the time domain and frequency domain to judge and evaluate the characteristics of the sound-emitting target under the detected water area.

This embodiment is an embodiment of a method for aerial detection of underwater sound-emitting targets using the above-mentioned embodiment of the above-mentioned aerial detection device for underwater sound-emitting targets. The principles and technical effects are similar and will not be repeated here.

The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: it can still be described in the foregoing embodiments Modifications are made to the recorded technical solutions, or equivalent replacements are made to some of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims (10)

1. one kind audible target aerial reconnaissance under water device, it is characterised in that include：Underwater sound generation unit, laser interference detection Unit and data acquisition and processing (DAP) unit；

The underwater sound generation unit includes signal generator and underwater sound wave exciter；

The signal generator is used for the drive signal for driving underwater sound wave exciter for generating predeterminated frequency；

The underwater sound wave exciter is produced and audible target for the water surface according to the drive signal in target water Acoustical signal frequency identical surface small amplitude wave；

The laser interference probe unit includes laser instrument, modulation light path, optical interference circuit and photodetector；

The laser instrument is used for the laser beam for launching preset wavelength；

The modulation light path is for carrying out expanding to the laser beam, beam splitting, and the laser beam after beam splitting is reflexed to institute State water surface；

The optical interference circuit is integrated coaxial for the measuring beam that reflects the water surface and reference beam, and makes the measurement Light beam and reference beam are interfered；

The photodetector is used for the light intensity signal for receiving the interference light；

The data acquisition and processing (DAP) unit is used to gathering and processing the light intensity signal, to be judged according to result and be assessed The characteristic of the audible target.

2. device according to claim 1, it is characterised in that the underwater sound generation unit also includes power amplifier；

The drive signal of predeterminated frequency of the power amplifier for generating to the signal generator is carried out at power amplification Reason.

3. device according to claim 1, it is characterised in that the data acquisition and processing (DAP) unit includes data collecting card Analysis module is processed with central authorities；

The data collecting card is used for the voltage signal for gathering and caching the light intensity signal；

The central authorities process analysis module for the signal processing of corresponding time domain and frequency domain being carried out to the voltage signal, being divided Analysis, and analysis result is shown.

4. device according to claim 3, it is characterised in that sampling of the data collecting card using highest 1.25MHz Frequency and 16 acquisition precisions.

5. device according to claim 3, it is characterised in that the central authorities process analysis module includes oscillograph and calculating Machine.

6. device according to claim 1, it is characterised in that the modulation light path include laser beam expanding lens, beam splitter with And first reflecting mirror；

The laser beam that the laser instrument sends first passes through the laser beam expanding lens and is expanded, then is divided into through the beam splitter , used as reference beam, another beam of laser is after first reflecting mirror reflection as the measurement for two beams, wherein beam of laser Light beam is irradiated on the water surface.

7. device according to claim 1, it is characterised in that the optical interference circuit include the second reflecting mirror, attenuator with And spike interference filter；

The reference beam through the attenuator, is returned with water surface scattering after second reflecting mirror reflection Measuring beam interfere to obtain interfering beam so that the interfering beam is after the spike interference filter, shine It is mapped to the detection window of the photodetector.

8. device according to claim 7, it is characterised in that the optical interference circuit also includes adjustable diaphragm；

The adjustable diaphragm is used for the size of the hot spot for adjusting the interfering beam.

9. device according to claim 1, it is characterised in that the underwater sound wave exciter includes pallesthesiometer.

10. a kind of aerial reconnaissance method of audible target under water based on claim 1-9 any one described device, its feature exist In, including：

The signal generator generates the drive signal for driving underwater sound wave exciter of predeterminated frequency；

Water surface of the underwater sound wave exciter according to the drive signal in target water produces the sound letter with audible target Number frequency identical surface small amplitude wave；

The laser instrument launches the laser beam of preset wavelength；

The modulation light path carries out expanding to the laser beam, beam splitting, and the laser beam after beam splitting is reflexed to the water Surface；

The measuring beam and reference beam integration that the water surface is reflected by the optical interference circuit is coaxial, and makes the measuring beam Interfere with reference beam；

The photodetector receives the light intensity signal of the interference light；

The data acquisition and processing (DAP) unit gathers and processes the light intensity signal, described to be judged according to result and be assessed The characteristic of audible target.