CN115825964A - Underwater target detection method and system based on microwave water surface vibration sensing - Google Patents

Abstract

The invention provides an underwater target detection method based on microwave water surface vibration sensing, which comprises the following steps: step S1: driving a microwave transceiver to sense water surface vibration through a carrying platform, and extracting water surface vibration information generated by underwater target underwater sound excitation; step S2: eliminating wave motion information and carrying platform motion information; and step S3: analyzing water surface vibration information generated by underwater target underwater acoustic excitation, and positioning the water surface vibration information to a target water area; and step S4: and detecting and positioning the target, and calculating the depth. The invention provides an underwater target detection method and system based on microwave water surface vibration sensing. The underwater target detection method solves the problems that maneuvering detection, remote detection, accurate target positioning and the like are difficult to realize in the existing underwater target detection method, and simultaneously solves the problems that the existing active sonar system is large in power and size, and passive sonar seriously depends on high and new materials and processes.

Description

Underwater target detection method and system based on microwave surface vibration perception

technical field

The invention relates to the technical field of underwater target detection, in particular to an underwater target detection method and system based on microwave water surface vibration perception.

Background technique

Underwater target detection is an important common application requirement in the fields of underwater environment perception, marine resource monitoring and development. At present, the detection of underwater targets mainly includes optical detection and acoustic detection.

Optical detection mainly uses imaging methods to identify targets. However, light waves attenuate exponentially underwater, and the detection distance is very limited. Acoustic detection mainly utilizes the good characteristics of sound propagation and reflection under water, including active sonar and passive sonar. Among them, the power and volume of the active sonar are large, and the passive sonar needs to be arranged in advance, and the low-frequency perception ability is weak, and the detection range is limited. In addition, the existing sonar detection methods have problems such as poor mobility and difficult detection of depth information.

Optics-based underwater target detection: Light waves are exponentially attenuated underwater, and the detection distance is limited. Acoustic-based underwater target detection: Active sonar has large power and volume, passive sonar needs to be arranged in advance, and has weak low-frequency perception ability and limited detection range. In addition, the existing sonar detection methods have problems such as poor mobility and difficult detection of depth information.

The invention proposes an underwater target detection method and system based on microwave water surface vibration perception, and uses a microwave transceiver and a carrying platform to quickly detect and locate the underwater target. It takes into account the low-frequency detection, mobile detection, and long-distance detection that are difficult to achieve in the existing underwater target detection, and solves the problems that the active sonar system has a large power and volume, and the passive sonar relies heavily on high-tech materials and processes.

Contents of the invention

In view of the defects in the prior art, the object of the present invention is to provide an underwater target detection method and system based on microwave water surface vibration perception.

An underwater target detection method based on microwave surface vibration perception provided by the present invention includes:

Step S1: Drive the microwave transceiver to sense the vibration of the water surface through the carrier platform, and extract the vibration information of the water surface generated by the underwater acoustic excitation of the underwater target;

Step S2: Eliminate wave motion information and carrier platform motion information;

Step S3: Analyze the water surface vibration information generated by the underwater acoustic excitation of the underwater target, and locate the target water area;

Step S4: Detect and locate the target, and calculate the depth.

Preferably, in the step S1:

The microwave interference radar is used to perceive the water surface vibration generated by the underwater acoustic excitation of the underwater target. The carrier platform carries the microwave interference radar so that its transmitting antenna faces the target water surface, and the microwave interference radar is controlled to emit microwave signals incident on the water surface to be detected. And receive the microwave signal to obtain the baseband signal. For the single-frequency continuous wave radar, methods including arctangent demodulation are used, and for the frequency-modulated continuous wave radar, the interferometric phase evolution tracking method is used to invert the fluctuation displacement information x(t) of the water surface:

为提取的干涉相位演变信息，t为时间；where λ is the wavelength of the microwave signal,

is the extracted interferometric phase evolution information, t is time;

The microwave transceiver includes: a continuous wave microwave signal source, a power divider, a power amplifier, a mixer, a low-pass filter, a conditioning circuit, a transceiver antenna and a processor;

The continuous wave microwave signal source is used to transmit continuous wave microwave signals, which are divided into two channels through the power divider, one is sent by the transmitting antenna through the power amplifier, and the other is input into the mixer, and the reflected signal received by the receiving antenna is mixed for processing. , the mixer is connected with the low-pass filter, the mixed frequency signal is input into the low-pass filter, the low-pass filter is connected with the conditioning circuit, and finally the baseband signal of the microwave transceiver is generated;

The transmitting and receiving antenna includes a transmitting antenna and a receiving antenna, and the number of the transmitting antenna and the receiving antenna is at least one.

Preferably, in the step S2:

According to the frequency range of sea surface waves, processing methods including high-pass filtering are used to eliminate ultra-low frequency wave motion components in water surface fluctuation displacement information;

The vibration interference component of the mobile body itself is eliminated by combining the motion information of the carrier platform with the method including vibration isolation platform and software algorithm filtering, so as to avoid the influence of the carrier platform's own vibration.

Preferably, in the step S3:

Analyze the water surface vibration information generated by underwater target underwater acoustic excitation, locate the target water area and calculate the target depth in combination with the position information of the carrier platform. The specific operations are as follows:

The water surface vibration information δ(t) generated by the underwater acoustic excitation of the underwater target will be extracted, and at the same time, methods including fast Fourier transform, short-time Fourier transform, and wavelet transform will be used for the water surface micro-amplitude vibration information for a period of time Perform analysis to obtain the frequency ω(t) of the slight vibration of the water surface;

According to the frequency range and frequency change law of the frequency characteristics ω′(t) of different underwater targets, compare the frequency ω(t) of the slight vibration of the water surface to find the target water area, and judge the underwater target category and the corresponding acoustic sound according to the prior knowledge. Source sound pressure level range P ₀ (dB).

Preferably, in said step S4:

According to the relationship between the water surface sound pressure and its excited water surface vibration, the water surface sound pressure is estimated:

P(ω,t)=ρvω(t)δ(t)

Among them, P(ω,t) represents the sound pressure near the water surface, ρ represents the density of water, v represents the propagation speed of sound underwater, ω represents the measured vibration frequency, and ω(t) is the frequency of slight vibration on the water surface ; δ(t) represents the water surface vibration information generated by the underwater acoustic excitation of the underwater target;

According to the underwater target sound source sound pressure level range P ₀ (dB) and spherical wave sound pressure attenuation law, the target distance D is obtained:

According to the present invention, an underwater target detection system based on microwave surface vibration perception includes:

Module M1: Drive the microwave transceiver through the carrier platform to sense the vibration of the water surface, and extract the vibration information of the water surface generated by the underwater acoustic excitation of the underwater target;

Module M2: Eliminate wave motion information and carrier platform motion information;

Module M3: Analyze the water surface vibration information generated by underwater target underwater acoustic excitation, and locate the target water area;

Module M4: detect and locate the target, and calculate the depth.

Preferably, in said module M1:

The microwave interference radar is used to perceive the water surface vibration generated by the underwater acoustic excitation of the underwater target. The carrier platform carries the microwave interference radar so that its transmitting antenna faces the target water surface, and the microwave interference radar is controlled to emit microwave signals incident on the water surface to be detected. And receive the microwave signal to obtain the baseband signal. For the single-frequency continuous wave radar, methods including arctangent demodulation are used, and for the frequency-modulated continuous wave radar, the interferometric phase evolution tracking method is used to invert the fluctuation displacement information x(t) of the water surface:

为提取的干涉相位演变信息，t为时间；where λ is the wavelength of the microwave signal,

is the extracted interferometric phase evolution information, t is time;

The microwave transceiver includes: a continuous wave microwave signal source, a power divider, a power amplifier, a mixer, a low-pass filter, a conditioning circuit, a transceiver antenna and a processor;

The continuous wave microwave signal source is used to transmit continuous wave microwave signals, which are divided into two channels through the power divider, one is sent by the transmitting antenna through the power amplifier, and the other is input into the mixer, and the reflected signal received by the receiving antenna is mixed for processing. , the mixer is connected with the low-pass filter, the mixed frequency signal is input into the low-pass filter, the low-pass filter is connected with the conditioning circuit, and finally the baseband signal of the microwave transceiver is generated;

The transmitting and receiving antenna includes a transmitting antenna and a receiving antenna, and the number of the transmitting antenna and the receiving antenna is at least one.

Preferably, in said module M2:

According to the frequency range of sea surface waves, processing methods including high-pass filtering are used to eliminate ultra-low frequency wave motion components in water surface fluctuation displacement information;

The vibration interference component of the mobile body itself is eliminated by combining the motion information of the carrier platform with the method including vibration isolation platform and software algorithm filtering, so as to avoid the influence of the carrier platform's own vibration.

Preferably, in said module M3:

Analyze the water surface vibration information generated by underwater target underwater acoustic excitation, locate the target water area and calculate the target depth in combination with the position information of the carrier platform. The specific operations are as follows:

The water surface vibration information δ(t) generated by the underwater acoustic excitation of the underwater target will be extracted, and at the same time, methods including fast Fourier transform, short-time Fourier transform, and wavelet transform will be used for the water surface micro-amplitude vibration information for a period of time Perform analysis to obtain the frequency ω(t) of the slight vibration of the water surface;

According to the frequency range and frequency change law of the frequency characteristics ω′(t) of different underwater targets, compare the frequency ω(t) of the slight vibration of the water surface to find the target water area, and judge the underwater target category and the corresponding acoustic sound according to the prior knowledge. Source sound pressure level range P ₀ (dB).

Preferably, in said module M4:

According to the relationship between the water surface sound pressure and its excited water surface vibration, the water surface sound pressure is estimated:

P(ω,t)=ρvω(t)δ(t)

Among them, P(ω,t) represents the sound pressure near the water surface, ρ represents the density of water, v represents the propagation speed of sound underwater, ω represents the measured vibration frequency, and ω(t) is the frequency of slight vibration on the water surface ; δ(t) represents the water surface vibration information generated by the underwater acoustic excitation of the underwater target;

According to the underwater target sound source sound pressure level range P ₀ (dB) and spherical wave sound pressure attenuation law, the target distance D is obtained:

Compared with the prior art, the present invention has the following beneficial effects:

1. The present invention proposes an underwater target detection method and system based on microwave water surface vibration perception, which utilizes a carrier platform to carry a microwave transceiver to identify and locate underwater targets by extracting water surface vibration information. Solve the difficulties in the existing underwater target detection methods that are difficult to achieve maneuver detection, long-distance detection and accurate target positioning

2. The present invention overcomes the problems that the existing active sonar system has large power and volume, and the passive sonar relies heavily on high-tech materials and techniques;

3. The present invention has strong low-frequency perception ability, wide detection range, good maneuverability and easy detection of depth information.

Description of drawings

Other characteristics, objects and advantages of the present invention will become more apparent by reading the detailed description of non-limiting embodiments made with reference to the following drawings:

Fig. 1 is a schematic diagram of the system of the present invention;

Fig. 2 is method flowchart of the present invention;

Fig. 3 is a system block diagram of the present invention.

Detailed ways

The present invention will be described in detail below in conjunction with specific embodiments. The following examples will help those skilled in the art to further understand the present invention, but do not limit the present invention in any form. It should be noted that those skilled in the art can make several changes and improvements without departing from the concept of the present invention. These all belong to the protection scope of the present invention.

Example 1:

According to an underwater target detection method based on microwave water surface vibration perception provided by the present invention, as shown in Fig. 1-Fig. 3, it includes:

Step S1: Drive the microwave transceiver to sense the vibration of the water surface through the carrier platform, and extract the vibration information of the water surface generated by the underwater acoustic excitation of the underwater target;

Step S2: Eliminate wave motion information and carrier platform motion information;

Step S3: Analyze the water surface vibration information generated by the underwater acoustic excitation of the underwater target, and locate the target water area;

Step S4: Detect and locate the target, and calculate the depth.

Preferably, in the step S1:

The microwave interference radar is used to perceive the water surface vibration generated by the underwater acoustic excitation of the underwater target. The carrier platform carries the microwave interference radar so that its transmitting antenna faces the target water surface, and the microwave interference radar is controlled to emit microwave signals incident on the water surface to be detected. And receive the microwave signal to obtain the baseband signal. For the single-frequency continuous wave radar, methods including arctangent demodulation are used, and for the frequency-modulated continuous wave radar, the interferometric phase evolution tracking method is used to invert the fluctuation displacement information x(t) of the water surface:

为提取的干涉相位演变信息，t为时间；where λ is the wavelength of the microwave signal,

is the extracted interferometric phase evolution information, t is time;

The microwave transceiver includes: a continuous wave microwave signal source, a power divider, a power amplifier, a mixer, a low-pass filter, a conditioning circuit, a transceiver antenna and a processor;

The continuous wave microwave signal source is used to transmit continuous wave microwave signals, which are divided into two channels through the power divider, one is sent by the transmitting antenna through the power amplifier, and the other is input into the mixer, and the reflected signal received by the receiving antenna is mixed for processing. , the mixer is connected with the low-pass filter, the mixed frequency signal is input into the low-pass filter, the low-pass filter is connected with the conditioning circuit, and finally the baseband signal of the microwave transceiver is generated;

The transmitting and receiving antenna includes a transmitting antenna and a receiving antenna, and the number of the transmitting antenna and the receiving antenna is at least one.

Preferably, in the step S2:

According to the frequency range of sea surface waves, processing methods including high-pass filtering are used to eliminate ultra-low frequency wave motion components in water surface fluctuation displacement information;

The vibration interference component of the mobile body itself is eliminated by combining the motion information of the carrier platform with the method including vibration isolation platform and software algorithm filtering, so as to avoid the influence of the carrier platform's own vibration.

Preferably, in the step S3:

Analyze the water surface vibration information generated by underwater target underwater acoustic excitation, locate the target water area and calculate the target depth in combination with the position information of the carrier platform. The specific operations are as follows:

The water surface vibration information δ(t) generated by the underwater acoustic excitation of the underwater target will be extracted, and at the same time, methods including fast Fourier transform, short-time Fourier transform, and wavelet transform will be used for the water surface micro-amplitude vibration information for a period of time Perform analysis to obtain the frequency ω(t) of the slight vibration of the water surface;

According to the frequency range and frequency change law of different underwater target frequency characteristics ω′(t), compare the frequency ω(t) of the slight vibration of the water surface, find the target water area, and judge the underwater target category and the corresponding acoustic sound according to the prior knowledge. Source sound pressure level range P ₀ (dB).

Preferably, in said step S4:

According to the relationship between the water surface sound pressure and its excited water surface vibration, the water surface sound pressure is estimated:

P(ω,t)=ρvω(t)δ(t)

Among them, P(ω,t) represents the sound pressure near the water surface, ρ represents the density of water, v represents the propagation speed of sound underwater, ω represents the measured vibration frequency, and ω(t) is the frequency of slight vibration on the water surface ; δ(t) represents the water surface vibration information generated by the underwater acoustic excitation of the underwater target;

According to the underwater target sound source sound pressure level range P ₀ (dB) and spherical wave sound pressure attenuation law, the target distance D is obtained:

Example 2:

Embodiment 2 is a preferred example of Embodiment 1 to describe the present invention more specifically.

Those skilled in the art can understand the underwater target detection method based on microwave water surface vibration sensing provided by the present invention as a specific implementation of the underwater target detection system based on microwave water surface vibration sensing, that is, the microwave water surface vibration sensing based The underwater target detection system can be realized by executing the steps of the underwater target detection method based on microwave water surface vibration perception.

According to the present invention, an underwater target detection system based on microwave surface vibration perception includes:

Module M1: Drive the microwave transceiver through the carrier platform to sense the vibration of the water surface, and extract the vibration information of the water surface generated by the underwater acoustic excitation of the underwater target;

Module M2: Eliminate wave motion information and carrier platform motion information;

Module M3: Analyze the water surface vibration information generated by underwater target underwater acoustic excitation, and locate the target water area;

Module M4: detect and locate the target, and calculate the depth.

Preferably, in said module M1:

The microwave interference radar is used to perceive the water surface vibration generated by the underwater acoustic excitation of the underwater target. The carrier platform carries the microwave interference radar so that its transmitting antenna faces the target water surface, and the microwave interference radar is controlled to emit microwave signals incident on the water surface to be detected. And receive the microwave signal to obtain the baseband signal. The single-frequency continuous wave radar uses methods including arctangent demodulation. For the frequency-modulated continuous wave radar, the interferometric phase evolution tracking method is used to invert the fluctuation displacement information x(t) of the water surface:

为提取的干涉相位演变信息，t为时间；where λ is the wavelength of the microwave signal,

is the extracted interferometric phase evolution information, t is time;

The microwave transceiver includes: a continuous wave microwave signal source, a power divider, a power amplifier, a mixer, a low-pass filter, a conditioning circuit, a transceiver antenna and a processor;

The continuous wave microwave signal source is used to transmit continuous wave microwave signals, which are divided into two channels through the power divider, one is sent by the transmitting antenna through the power amplifier, and the other is input into the mixer, and the reflected signal received by the receiving antenna is mixed for processing. , the mixer is connected with the low-pass filter, the mixed frequency signal is input into the low-pass filter, the low-pass filter is connected with the conditioning circuit, and finally the baseband signal of the microwave transceiver is generated;

The transmitting and receiving antenna includes a transmitting antenna and a receiving antenna, and the number of the transmitting antenna and the receiving antenna is at least one.

Preferably, in said module M2:

According to the frequency range of sea surface waves, processing methods including high-pass filtering are used to eliminate ultra-low frequency wave motion components in water surface fluctuation displacement information;

The vibration interference component of the mobile body itself is eliminated by combining the motion information of the carrier platform with the method including vibration isolation platform and software algorithm filtering, so as to avoid the influence of the carrier platform's own vibration.

Preferably, in said module M3:

Analyze the water surface vibration information generated by underwater target underwater acoustic excitation, locate the target water area and calculate the target depth in combination with the position information of the carrier platform. The specific operations are as follows:

The water surface vibration information δ(t) generated by the underwater acoustic excitation of the underwater target will be extracted, and at the same time, methods including fast Fourier transform, short-time Fourier transform, and wavelet transform will be used for the water surface micro-amplitude vibration information for a period of time Perform analysis to obtain the frequency ω(t) of the slight vibration of the water surface;

According to the frequency range and frequency change law of the frequency characteristics ω′(t) of different underwater targets, compare the frequency ω(t) of the slight vibration of the water surface to find the target water area, and judge the underwater target category and the corresponding acoustic sound according to the prior knowledge. Source sound pressure level range P ₀ (dB).

Preferably, in said module M4:

According to the relationship between the water surface sound pressure and its excited water surface vibration, the water surface sound pressure is estimated:

P(ω,t)=ρvω(t)δ(t)

Among them, P(ω,t) represents the sound pressure near the water surface, ρ represents the density of water, v represents the propagation speed of sound underwater, ω represents the measured vibration frequency, and ω(t) is the frequency of slight vibration on the water surface ; δ(t) represents the water surface vibration information generated by the underwater acoustic excitation of the underwater target;

According to the underwater target sound source sound pressure level range P ₀ (dB) and spherical wave sound pressure attenuation law, the target distance D is obtained:

Example 3:

Embodiment 3 is a preferred example of Embodiment 1 to describe the present invention more specifically.

Aiming at the problems and defects of existing underwater target detection, the present invention proposes an underwater target detection method and system based on microwave water surface vibration perception. Firstly, the carrier platform is used to carry the microwave transceiver to sense the water surface fluctuation information. By extracting the water surface vibration information generated by the underwater acoustic excitation of the underwater target, combined with the underwater acoustic characteristics of the detection target, the target detection and positioning are carried out.

The invention relates to an underwater target detection method based on microwave water surface vibration perception:

Step 1, drive the microwave transceiver to sense the vibration of the water surface through the carrier platform including the aircraft, and extract the vibration information of the water surface generated by the underwater acoustic excitation of the underwater target;

Step 2: Analyze the water surface vibration information generated by the underwater acoustic excitation of the underwater target, locate the target water area, and perform target detection and positioning.

The method for the microwave transceiver in step 1 to sense vibrations on the water surface is:

Step 1.1 utilizes the microwave transceiver to measure the water surface fluctuation information including the water surface vibration information generated by the underwater acoustic excitation of the underwater target;

Step 1.2 eliminates the wave motion component in the water surface fluctuation information;

Ultra-low frequency wave motion components are eliminated by cancellation methods including high-pass filtering.

Step 1.3 eliminates the interference information of the mobile body itself, and finally extracts the water surface vibration information generated by the underwater acoustic excitation of the underwater target.

Eliminate the vibration interference component of the carrier platform itself through methods including vibration isolation pan/tilt and software algorithm filtering.

The target water area positioning and target depth calculation methods in step 2 are:

Step 2.1: Based on the prior knowledge of the underwater acoustic characteristics of the target to be detected, the matching vibration water area is detected to realize the positioning of the target water area and the identification of the underwater target category.

The underwater acoustic characteristics of the target include frequency range, frequency variation characteristics and sound source sound pressure level.

In step 2.2, the target depth is calculated according to the attenuation relationship between the underwater sound pressure and the propagation distance.

P(ω,t)=ρvω(t)δ(t)

Among them, P(ω,t) represents the sound pressure near the water surface, ρ represents the density of water, ω represents the measured vibration frequency, v represents the propagation speed of sound underwater, and δ(t) represents the extracted underwater target water Water surface vibration information generated by acoustic excitation. According to the underwater target sound pressure level range _P0 (dB) and spherical wave sound pressure attenuation law, the target distance D can be obtained:

The invention relates to an underwater target detection system based on microwave water surface vibration perception, comprising: a carrying platform, a microwave transceiver, a water surface vibration information extraction module, a target detection and identification module and a memory.

Among them, the carrier platform is used to carry millimeter-wave radar for large-scale mobile measurement on the water surface; the microwave transceiver is used to transmit and receive continuous wave microwave signals, and generate the baseband signal of the microwave transceiver; the water surface vibration information extraction module is used to analyze the baseband signal of the microwave transceiver The time-domain information of the fluctuation displacement of the water surface is collected and processed, and the natural vibration of the microwave transceiver generated by the operation of the carrier platform is suppressed, and finally the water surface vibration information excited by the underwater target underwater is extracted. The target detection and identification module is used to invert the water surface vibration information into underwater target detection and target location information. The memory is used to store information including water surface vibration information, underwater target detection and identification information and positioning information.

The microwave transceiver includes: a continuous wave microwave signal source, a power divider, a power amplifier, a mixer, a low-pass filter, a conditioning circuit, a transceiver antenna and a processor. The continuous wave microwave signal source is used to transmit continuous wave microwave signals, which are divided into two channels through the power divider, one is sent by the transmitting antenna through the power amplifier, and the other is input into the mixer, and the reflected signal received by the receiving antenna is mixed for processing. , the mixer is connected with the low-pass filter, the mixed frequency signal is input into the low-pass filter, the low-pass filter is connected with the conditioning circuit, and finally the baseband signal of the microwave transceiver is generated.

The transmitting and receiving antenna includes a transmitting antenna and a receiving antenna, and the number of the transmitting antenna and the receiving antenna is at least one.

Example 4:

Embodiment 4 is a preferred example of Embodiment 1 to describe the present invention more specifically.

As shown in FIG. 1 , it is a schematic diagram of an underwater target detection method and system based on microwave water surface vibration sensing according to the present invention. The carrier platform is equipped with a microwave transceiver, and the underwater target identification and positioning are carried out by extracting the water surface vibration information generated by the underwater acoustic excitation of the underwater target.

As shown in Figure 2, it is a flowchart of an underwater target detection method based on microwave surface vibration perception of the present invention, including the following steps:

Step 1, use the microwave interference radar to perceive the water surface vibration generated by the underwater acoustic excitation of the underwater target, the specific operation is as follows:

Step 1.1, the carrier platform carries the microwave interference radar so that its transmitting antenna faces the target water surface, and controls the microwave interference radar to emit microwave signals incident on the water surface to be detected. The microwave transceiver transmits and receives the microwave signal to obtain the baseband signal. The single frequency continuous wave radar includes For methods including arctangent demodulation, the interferometric phase evolution tracking method can be used to invert the fluctuation displacement information of the water surface for frequency modulated continuous wave (FMCW) radar:

为提取的干涉相位演变信息。where λ is the wavelength of the microwave signal,

is the extracted interferometric phase evolution information.

Step 1.2, according to the frequency range of sea surface waves, use processing methods including high-pass filtering to eliminate ultra-low frequency wave motion components in the water surface fluctuation displacement information.

In step 1.3, the vibration interference component of the mobile body itself is eliminated by combining the motion information of the carrier platform with the method including the vibration isolation platform and software algorithm filtering, so as to avoid the influence of the carrier platform's own vibration.

Step 2: Analyze the water surface vibration information generated by the underwater acoustic excitation of the underwater target, and combine the position information of the carrier platform to locate the target water area and calculate the target depth. The specific operations are as follows:

In step 2.1, the water surface vibration information δ(t) generated by the underwater acoustic excitation of the underwater target will be extracted. The method in the paper is analyzed, and the frequency ω(t) of the slight vibration of the water surface is obtained.

Step 2.2, according to the frequency range and frequency change law of different underwater target frequency characteristics ω′(t), compare the frequency ω(t) of the slight amplitude vibration of the water surface, find the target water area, and judge the underwater target category and frequency according to the prior knowledge. Corresponding sound source sound pressure level range P ₀ (dB).

Step 2.3, according to the relationship between the water surface sound pressure and its excited water surface vibration, estimate the water surface sound pressure:

P(ω,t)=ρvω(t)δ(t)

Among them, P(ω,t) represents the sound pressure near the water surface, ρ represents the density of water, ω represents the measured vibration frequency, v represents the propagation speed of sound underwater, and δ(t) represents the underwater sound excitation of the underwater target water surface vibration information. According to the underwater target sound source sound pressure level range _P0 (dB) and spherical wave sound pressure attenuation law, the target distance D can be obtained:

As shown in Fig. 3, the present invention relates to an underwater target detection system based on microwave water surface vibration perception, including: a carrier platform, a microwave transceiver, a water surface vibration information extraction module, a target detection and identification module, and a memory. Among them, the carrier platform is used to carry millimeter-wave radar for large-scale mobile measurement on the water surface; the microwave transceiver is used to transmit and receive continuous wave microwave signals, and generate the baseband signal of the microwave transceiver; the water surface vibration information extraction module is used to analyze the baseband signal of the microwave transceiver The time-domain information of the fluctuation displacement of the water surface is collected and processed, and the natural vibration of the microwave transceiver generated by the operation of the carrier platform is suppressed, and finally the water surface vibration information excited by the underwater target underwater is extracted. The target detection and identification module is used to invert the water surface vibration information into underwater target detection and target location information. The memory is used to store information including water surface vibration information, underwater target detection and identification information and positioning information.

The microwave transceiver includes: a continuous wave microwave signal source, a power divider, a power amplifier, a mixer, a low-pass filter, a conditioning circuit, a transceiver antenna and a processor. The continuous wave microwave signal source is used to transmit continuous wave microwave signals, which are divided into two channels through the power divider, one is sent by the transmitting antenna through the power amplifier, and the other is input into the mixer, and the reflected signal received by the receiving antenna is mixed for processing. , the mixer is connected with the low-pass filter, the mixed frequency signal is input into the low-pass filter, the low-pass filter is connected with the conditioning circuit, and finally the baseband signal of the microwave transceiver is generated.

The transmitting and receiving antenna includes a transmitting antenna and a receiving antenna, and the number of the transmitting antenna and the receiving antenna is at least one.

Those skilled in the art know that, in addition to realizing the system, device and each module thereof provided by the present invention in a purely computer-readable program code mode, the system, device and each module thereof provided by the present invention can be completely programmed by logically programming the method steps. The same program is implemented in the form of logic gates, switches, application specific integrated circuits, programmable logic controllers, and embedded microcontrollers, among others. Therefore, the system, device and each module provided by the present invention can be regarded as a hardware component, and the modules included in it for realizing various programs can also be regarded as the structure in the hardware component; A module for realizing various functions can be regarded as either a software program realizing a method or a structure within a hardware component.

Specific embodiments of the present invention have been described above. It should be understood that the present invention is not limited to the specific embodiments described above, and those skilled in the art may make various changes or modifications within the scope of the claims, which do not affect the essence of the present invention. In the case of no conflict, the embodiments of the present application and the features in the embodiments can be combined with each other arbitrarily.

Claims (10)

1. An underwater target detection method based on microwave water surface vibration sensing is characterized by comprising the following steps:

step S1: driving a microwave transceiver to sense water surface vibration through a carrying platform, and extracting water surface vibration information generated by underwater target underwater sound excitation;

step S2: eliminating wave motion information and carrying platform motion information;

and step S3: analyzing water surface vibration information generated by underwater target underwater acoustic excitation, and positioning the water surface vibration information to a target water area;

and step S4: and detecting and positioning the target, and calculating the depth.

2. The method for detecting underwater targets based on microwave water surface vibration perception according to claim 1, wherein in the step S1:

the method comprises the following steps that the microwave interference radar is utilized to sense water surface vibration generated by underwater target underwater acoustic excitation, the carrying platform carries the microwave interference radar, a transmitting antenna of the microwave interference radar faces the target water surface, the microwave interference radar is controlled to transmit microwave signals to be incident on the water surface to be detected, the microwave transceiver obtains baseband signals by transmitting and receiving the microwave signals, the method including arc tangent demodulation is used for a single-frequency continuous wave radar, and the fluctuation displacement information x (t) of the water surface is inverted by an interference phase evolution tracking method for a frequency modulation continuous wave radar:

wherein lambda is the wavelength of the microwave signal,

for the extracted interferometric phase evolution information, t is time.

3. The method for detecting underwater targets based on microwave water surface vibration perception according to claim 1, wherein in the step S2:

according to the sea surface wave frequency range, eliminating the ultralow frequency wave motion component in the water surface fluctuation displacement information by using a processing method including high-pass filtering;

the vibration interference component of the body of the mobile body is eliminated by combining the motion information of the carrying platform through a method including a vibration isolation cradle head and software algorithm filtering, and the influence of the self vibration of the carrying platform is avoided.

4. The method for detecting underwater targets based on microwave water surface vibration sensing according to claim 1, wherein in the step S3:

analyzing water surface vibration information generated by underwater target underwater acoustic excitation, positioning a target water area by combining position information of a carrying platform and calculating target depth, and specifically operating as follows:

extracting water surface vibration information delta (t) generated by underwater target underwater acoustic excitation, and analyzing the water surface micro-amplitude vibration information for a period of time by using methods including fast Fourier transform, short-time Fourier transform and wavelet transform to obtain the frequency omega (t) of the water surface micro-amplitude vibration;

comparing the frequency omega (t) of the micro-amplitude vibration of the water surface according to the frequency range and the frequency change rule of the frequency characteristic omega' (t) of different underwater targets to find a target water area, and judging the underwater target type and the corresponding sound pressure level range P of the sound source according to the priori knowledge ₀ (dB)。

5. The method for detecting underwater targets based on microwave water surface vibration sensing according to claim 1, wherein in the step S4:

estimating the water surface sound pressure according to the relation between the water surface sound pressure and the excited water surface vibration:

P(ω,t)＝ρvω(t)δ(t)

wherein P (ω, t) represents the sound pressure near the water surface, ρ represents the density of water, v represents the propagation velocity of sound under water, ω represents the measured vibration frequency, and ω (t) is the frequency of the water surface micro-amplitude vibration; delta (t) represents the water surface vibration information generated by underwater target underwater acoustic excitation;

according to the sound pressure level range P of the underwater target sound source ₀ (dB) and a spherical wave sound pressure attenuation rule to obtain a target distance D:

6. an underwater target detection system based on microwave water surface vibration sensing, comprising:

a module M1: driving a microwave transceiver to sense water surface vibration through a carrying platform, and extracting water surface vibration information generated by underwater target underwater sound excitation;

a module M2: eliminating wave motion information and carrying platform motion information;

a module M3: analyzing water surface vibration information generated by underwater target underwater acoustic excitation, and positioning the water surface vibration information to a target water area;

a module M4: and detecting and positioning the target, and calculating the depth.

7. The microwave water surface vibration sensing-based underwater object detection system according to claim 6, wherein in the module M1:

the method comprises the following steps that the microwave interference radar is utilized to sense water surface vibration generated by underwater target underwater acoustic excitation, the carrying platform carries the microwave interference radar, a transmitting antenna of the microwave interference radar faces the target water surface, the microwave interference radar is controlled to transmit microwave signals to be incident on the water surface to be detected, the microwave transceiver obtains baseband signals by transmitting and receiving the microwave signals, the method including arc tangent demodulation is used for a single-frequency continuous wave radar, and the fluctuation displacement information x (t) of the water surface is inverted by an interference phase evolution tracking method for a frequency modulation continuous wave radar:

wherein lambda is the wavelength of the microwave signal,

extracting interference phase evolution information, wherein t is time;

the microwave transceiver includes: the device comprises a continuous wave microwave signal source, a power divider, a power amplifier, a mixer, a low-pass filter, a conditioning circuit, a transmitting-receiving antenna and a processor;

the continuous wave microwave signal source is used for transmitting continuous wave microwave signals, the continuous wave microwave signals are divided into two paths through the power divider, the two paths are transmitted by the transmitting antenna through the power amplifier, one path is input into the frequency mixer and is subjected to frequency mixing processing with reflected signals received by the receiving antenna, the frequency mixer is connected with the low-pass filter, the frequency mixing signals are input into the low-pass filter, the low-pass filter is connected with the conditioning circuit, and finally baseband signals of the microwave transceiver are generated;

the receiving and transmitting antenna comprises a transmitting antenna and a receiving antenna, and the number of the transmitting antenna and the receiving antenna is at least 1.

8. The microwave water surface vibration sensing-based underwater object detection system according to claim 6, wherein in the module M2:

according to the sea surface wave frequency range, eliminating the ultralow frequency wave motion component in the water surface fluctuation displacement information by using a processing method including high-pass filtering;

the vibration interference component of the body of the mobile body is eliminated by combining the motion information of the carrying platform through a method including a vibration isolation cradle head and software algorithm filtering, and the influence of the self vibration of the carrying platform is avoided.

9. The microwave water surface vibration sensing-based underwater object detection system of claim 6, wherein in the module M3:

analyzing water surface vibration information generated by underwater target underwater acoustic excitation, positioning a target water area by combining position information of a carrying platform and calculating target depth, and specifically operating as follows:

extracting water surface vibration information delta (t) generated by underwater target underwater acoustic excitation, and analyzing the water surface micro-amplitude vibration information for a period of time by using methods including fast Fourier transform, short-time Fourier transform and wavelet transform to obtain the frequency omega (t) of the water surface micro-amplitude vibration;

comparing the frequency omega (t) of the micro-amplitude vibration of the water surface according to the frequency range and the frequency change rule of the frequency characteristics omega' (t) of different underwater targets to find a target water area, and judging the underwater target type and the corresponding sound pressure level range P of the sound source according to the priori knowledge ₀ (dB)。

10. The microwave water surface vibration sensing-based underwater object detection system according to claim 6, wherein in the module M4:

estimating the water surface sound pressure according to the relation between the water surface sound pressure and the excited water surface vibration:

P(ω,t)＝ρvω(t)δ(t)

wherein P (ω, t) represents the sound pressure near the water surface, ρ represents the density of water, v represents the propagation velocity of sound under water, ω represents the measured vibration frequency, and ω (t) is the frequency of the water surface micro-amplitude vibration; delta (t) represents the water surface vibration information generated by underwater target underwater acoustic excitation;

according to the sound pressure level range P of the underwater target sound source ₀ (dB) and a spherical wave sound pressure attenuation rule to obtain a target distance D:

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