JP3049260B2 - Target signal detection method and device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a target signal detecting method and a target signal detecting apparatus for transmitting sound waves into water, receiving the reverberation sound thereof, and automatically detecting and classifying the reverberation sound from a target.

[0002]

2. Description of the Related Art In general, this kind of target signal detecting device is
It is used to support the target signal detection work that has been performed based on the experience and intuition of the operator. In other words, the target signal detection device is used as an aid when the operator visually confirms the output image of the display device or directly hears the reverberation sound to perform a target signal detection operation.

[0003] A conventional target signal detecting device includes a transducer, a signal processing unit, a signal detecting unit, a target detecting unit, a target classifying unit, a weighting table, and a display unit.
A plurality of electroacoustic transducers are provided, and these electroacoustic transducers are arranged in a predetermined arrangement. The transmitter / receiver transmits sound waves into the water and receives echoes from the target.

[0004] A signal processing unit inputs a received signal received by the transmitter / receiver, improves an S / N ratio, emphasizes a plurality of characteristics of the received signal, and generates an amplitude-based signal (amplitude, azimuth). ), Phase error variance signal (phase error variance, azimuth), and Doppler analysis signal (spectrum)
Is output.

[0005] The signal detection unit extracts a signal that seems to be a target for each of the three time-series signals output from the signal processing unit to obtain a target signal. Further, the signal is extracted from a section of the extracted target signal. The feature amount of the feature element is calculated.

The target detection unit integrates the target signals for each of the three systems extracted by the signal detection unit based on the positions calculated in the respective systems, calculates an integrated position, and calculates the integrated position. The characteristic element of the target signal of each system is output.

[0007] The target classifying section weights each of the integrated feature elements of each system output from the target detecting section with reference to a weighting table created in advance, and further performs weighting. A certainty factor is calculated from each of the obtained feature elements, it is determined whether or not the received signal is a signal from the target based on the certainty factor, and the position of the target signal and the like are output to the display unit.

As described above, the target detection rate is improved by displaying the position of the target signal and the like.

[0009]

By the way, an amplitude system signal (amplitude, direction), a phase error dispersion system signal (phase error dispersion value, direction), and a Doppler analysis system used as characteristic elements in a conventional target signal detecting apparatus. It is generally known that a signal (spectrum) changes based on a target aspect. For this reason, even if the target is detected under the same condition, if the aspect of the target is different, there is a problem that the certainty of the target changes according to the aspect and stable detection cannot be performed.

An object of the present invention is to provide a target signal detection method and apparatus capable of stably detecting a target.

[0011]

According to the present invention, there is provided a target signal detecting method for transmitting a sound wave into water and detecting a received signal obtained by receiving a reverberation sound from a target. A time-series signal representing the amplitude value and direction of the received signal, a time-series signal representing the phase error variance value and direction of the received signal, and a time-series signal representing the spectrum and direction of the received signal are extracted from the received signal. Extracting a time-series signal representing an amplitude value and a direction of the received signal, and extracting a signal whose amplitude value exceeds a preset first threshold value. A first step of detecting the signal as a target-like signal,
According to the time series continuity of the signal which seems to be the target,
Calculating the signal length of the target-like signal as a first signal length, and detecting the first target-like signal as a first target signal when the first signal length is within a predetermined range. And applying an arbitrary straight line to the time series-azimuth coordinate distribution of the amplitude of the first target signal section based on the time series amplitude and azimuth of the first target signal section, The amplitude value at the point is regarded as the mass of the mass point, the slope of the straight line where the moment of each amplitude or the rotational moment applied to the straight line becomes zero is calculated, and the slope is calculated as the target aspect representing the relative direction of the target. A third step of calculating a target detection position indicated by an azimuth and a distance of the first target signal and a maximum value of the amplitude value;
An amplitude-based signal detection step comprising the steps of: inputting a time-series signal representing a phase error variance value and an azimuth of the received signal, and generating a signal in which the phase error variance value falls below a second threshold set in advance; A fifth step of detecting as a second target-like signal; and calculating a signal length of the second target-like signal as a second signal length in accordance with the time-series continuity of the second target-like signal. When the second signal length is within a predetermined range, the second target-like signal is converted to a second signal.
And a seventh step of calculating a target detection position indicated by an azimuth and a distance of the second target signal and a minimum value of the phase error variance value. System signal detection step, an eighth step of inputting a time-series signal representing the spectrum of the received signal and the azimuth of the received signal and removing a reverberation signal from the spectrum of the received signal, and the same time in the spectrum of the received signal. A ninth step of extracting the maximum spectrum value from the spectrum group of the above, and a tenth step of detecting a signal having the maximum spectrum value exceeding a third threshold value set as a third target-like signal And the third
The signal length of the third target-like signal is calculated as a third signal length based on the time-series continuity and frequency continuity of the target-like signal, and the third signal length is predetermined. An eleventh step of detecting the third target-like signal as a third target signal when it is within the range; a target detection position indicated by an azimuth and a distance of the third target signal; a maximum value of the spectrum; A Doppler analysis signal detection step comprising: a twelfth step of calculating a frequency corresponding to the spectrum showing the maximum value; and a target position by integrating the first to third target signals to calculate a target position. Calculating a target information as information; and performing weighting on the target information based on a relative direction of the target to obtain a target of the integrated target signal based on the target information as weighted target information. Target signal detecting method characterized by having a confidence factor calculation step of calculating a confidence factor indicating the degree of Rashi is obtained.

Further, according to the present invention, in a target signal detecting device for transmitting a sound wave into water and detecting a received signal obtained by receiving a reverberation sound from a target, the target sound signal is transmitted and the received signal is detected. A transmitter / receiver to receive, an amplitude system signal indicating an amplitude and a direction according to the reception signal, a phase error dispersion system signal indicating a phase error variance value and a direction, and a Doppler analysis system signal indicating a spectrum of the reception signal And a signal processing unit that extracts a signal that seems to be a target for each system according to the amplitude system signal, the phase error variance system signal, and the Doppler analysis system signal, and sets the extracted signals as first to third target signals, respectively. To output the time series data of the amplitude and the azimuth corresponding to the target section detected in the amplitude system while calculating and outputting the characteristic amount of the feature element from the section of the third target signal. A detection unit that integrates the first to third target signals based on the positions calculated in the respective systems to calculate an integrated position, and from time-series data of amplitude and azimuth corresponding to a target section; A target detection unit that calculates a target aspect and outputs a position of each system, a target aspect, and a feature element of a target signal of each integrated system, and a feature amount of the feature element of each integrated system. With reference to a weighting table for each predetermined target aspect based on the target aspect, weighting is performed, a certainty factor is calculated from each weighted feature element, and a received signal is targeted based on the certainty factor. And a target classifying unit that determines whether or not the signal is a signal from the target, and outputs the position of the target signal to a display unit. The target detection unit calculates the aspect of the target by using the first target signal section. of An arbitrary straight line is applied to the distribution of the time series-azimuth coordinates of the amplitude of the first target signal section based on the amplitude and the azimuth of the series, and the amplitude value at the coordinate point of each amplitude is regarded as the mass of the mass point. A target signal detection device, wherein the inclination of a straight line where the moment or the rotational moment of each amplitude added to the straight line is zero is calculated and the inclination is calculated as a target aspect representing a relative direction of the target. can get.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the drawings.

Referring to FIG. 1, the illustrated target signal detecting apparatus extracts and integrates a plurality of characteristic elements, for example, amplitude and phase error variance values of a received signal based on a reverberation sound from a target. By calculating the likelihood of a reverberant sound (hereinafter referred to as a certainty factor) from the characteristic elements of the above, it is determined whether or not the signal is a signal from the target.

The transducer 1 has a plurality of electroacoustic transducers, and these electroacoustic transducers are arranged in a predetermined arrangement. The transmitter / receiver 1 transmits a sound wave into the water and receives a reverberation sound from the target as a reception signal. The signal processing unit 2 receives the received signal received by the transmitter / receiver 1 to improve the S / N ratio and emphasize a plurality of characteristics of the received signal, thereby obtaining an amplitude-based signal (amplitude, direction). , A phase error variance system signal (phase error variance value, direction), and a Doppler analysis system signal (spectrum).

The signal detection unit 3 extracts a signal that seems to be a target for each of the three time-series signals output from the signal processing unit 2 to obtain a target signal, and further extracts a target signal section from the extracted target signal section. It calculates and outputs the characteristic amount of the feature element included in the signal, and outputs time series data of the amplitude and the azimuth corresponding to the target section detected in the amplitude system.

The target detection unit 4 integrates the target signals for each of the three systems extracted by the signal detection unit 3 based on the position calculated in each system, calculates the integrated position, and calculates the target position. The target aspect is calculated from the time series data of the amplitude and the azimuth corresponding to the section, and the position, the target aspect, and the characteristic element of the integrated target signal of each system are output.

The target classifying unit 5 is configured to generate, for each of the integrated feature elements of the respective systems output from the target detecting unit 4, a target aspect created in advance based on the calculated aspect. Weighting is performed with reference to the weighting table 6, a certainty factor is calculated from each weighted feature element, and it is determined whether the received signal is a signal from a target based on the certainty factor. Display part 7
Output to

Next, the signal processing section 2 will be described in detail with reference to FIG.

The signal processing unit 2 includes a split beam forming unit 2
01, and the split beam forming unit 201 includes:
The output signals of the plurality of electroacoustic transducers from the transmitter / receiver 1 are phased to form a plurality of left and right receiving beams (split beams) each having the same receiving directivity in an arbitrary direction.

The band rejection filter 202 extracts a signal in a frequency band that can be specified in advance from use conditions and the like from the two left and right reception beams obtained by the split beam forming unit 201. The correlation operation unit 203 includes the band element filter 2
A correlation operation is performed between two reception beam signals on the left and right sides of a specific frequency band extracted in step S02.

The phase difference calculating section 204 includes a correlation calculating section 203
Is used to calculate the phase difference between the left and right reception beam outputs, and converts this phase difference into the reception signal azimuth (phase). The output detection unit 205 converts the amplitude output together with the received signal azimuth calculated by the phase difference detection unit 204 into an absolute amplitude, and outputs the received signal azimuth and the absolute amplitude (hereinafter simply referred to as amplitude) to the signal detection unit 3. Output. Hereinafter, a system that outputs the direction and amplitude of the received signal is referred to as an amplitude system.

The phase error variance calculation unit 206 calculates a phase variation (dispersion value) within a time interval that can be specified in advance from use conditions and the like, based on the azimuth of the received signal from the phase difference detection unit 204, and receives this. The signal is output to the signal detector 3 together with the signal direction. Hereinafter, a system that outputs the azimuth and the phase error dispersion value of the received signal is referred to as a phase error dispersion system.

The configuration of the amplitude system and the phase error dispersion system described above is described in, for example, Japanese Patent Application Laid-Open No. 59-72073.

On the other hand, the preformed bead forming section 207
Phasing the output signals of a plurality of electroacoustic transducers of the transducer 1 to form a plurality of single receiving beams (preformed beams) each having the same receiving directivity in an arbitrary direction. I do. The band rejection filter 208 extracts a signal in a frequency band that can be specified in advance by use conditions or the like from the single received beam output obtained by the preformed beam forming unit 207. The FFT 209 sequentially receives the reception signals output from the bandpass filter 208,
This is sampled in a time section that can be specified in advance from use conditions and the like, and a fast Fourier transform operation is performed for each time section to obtain a spectrum for each time. Then, the result is output to the signal detection unit 3 together with the direction of the reception beam. Hereinafter, a system that outputs the azimuth of the received signal and its spectrum is referred to as a Doppler analysis system.

Next, the signal detector 3 will be described in detail with reference to FIG. Here, description will be given for each of the amplitude system, the phase error variance system, and the Doppler analysis system.

First, in the amplitude-based signal detection processing, the amplitude threshold processing section 301 receives the azimuth and amplitude of the received signal output from the output detection section 205 shown in FIG. Threshold processing is performed for each sampling.

The signal length threshold value processing unit 302 calculates the length of a signal which seems to be a target exceeding the threshold value, using the amplitude subjected to the threshold value processing by the amplitude threshold value processing unit 301. Further, the signal length threshold processing unit 302 performs threshold processing on the calculated signal length by using a minimum value and a maximum value of a target length range that can be arbitrarily set in advance according to use conditions and the like. If the signal length is within this range, the signal section is set as a target signal section, and the amplitude, azimuth, number of times of sampling, and signal length of the received signal in this section are output to the aspect calculation section 303. Here, the number of times of sampling is a value indicating the number of times of sampling from a reference point (corresponding to a distance of 0 m) of the received signal.

The aspect calculation section 303 calculates a target aspect based on the amplitude, azimuth, number of samplings, and signal length of the signal in the target signal section output from the signal length threshold processing section 302, and outputs the signal in the target signal section. , The azimuth, the target aspect, the number of times of sampling, and the signal length are output to the position calculator 304.

Here, the method of calculating the aspect will be specifically described with reference to FIGS.

Now, consider the distribution of the signal amplitude in the target section on the azimuth axis and the sampling frequency axis (FIG. 4). Next, when the maximum value of the amplitude is extracted and the origin is used as the origin, a straight line Y = AX passing through this point is given. When the amplitude value of the amplitude is regarded as the mass, each point of the amplitude (each mass point) (Fig. 5). Then, the slope A of the straight line that minimizes the sum of the rotational moments defined for each mass point of each amplitude is regarded as the target aspect.

That is, the target aspect has the maximum value of the amplitude as the rotation center, and the sum of the rotation moments by the respective amplitudes acting on the straight line Y = AX taking this point corresponds to the slope A of the straight line at which it becomes the minimum.

Now, assuming that the rotational moment for each mass point is Mi and the inclination of the straight line is A, the target aspect will be A that satisfies Equation 1.

[0034]

(Equation 1) Here, Mi is calculated by Expression 2.

[0035]

(Equation 2) In Equation 2, Wi is an amplitude value of each amplitude, L1i, L2i.
Indicates the distance defined in FIG. The direction in which the force of each rotational moment Mi acts is the direction defined in FIG. 7 in each quadrant, where the origin is the maximum value of the amplitude and the Y axis is a straight line Y = AX.

The point P necessary for calculating L2i and L1i is
The coordinate positions Xi and Yi of 1i are the angles defined in FIG.
It is calculated using Equation 3 based on the side and the coordinate position.

[0037]

(Equation 3) Here, xi and yi, which are the position coordinates of each amplitude, are given by Equation 4
Use

[0038]

(Equation 4) Referring again to FIG. 3, position calculating section 304 determines the amplitude, azimuth, target aspect, number of samplings, and the like of the signal in the target signal section output from aspect calculating section 303.
And the maximum value of the amplitude based on the signal length. Further, the sampling number and the azimuth corresponding to the maximum value of the amplitude are extracted, the distance is calculated from the sampling number, and the azimuth is corrected for the azimuth. After the above processing,
The position calculation unit 304 outputs the target direction, the distance, the target aspect, the maximum value of the amplitude (hereinafter, referred to as signal S / N), and the signal length to the target detection unit 4.

Next, in the signal detection processing of the phase error dispersion system, the phase error dispersion threshold processing section 305 inputs the azimuth and the phase error dispersion value of the received signal output from the phase error calculation section 206 shown in FIG. Then, threshold processing is performed on the successively input phase error variance values for each sampling.

The signal length threshold value processing unit 306 calculates the length of a signal that is likely to be below the threshold value using the phase error variance value subjected to the threshold value processing by the phase error variance value threshold value processing unit 305. Further, the signal threshold processing unit 306 performs threshold processing on the calculated signal length with a minimum value and a maximum value of a target length range that can be arbitrarily set in advance according to use conditions and the like. If the signal length is within this range, the signal section is set as a target signal section, and the phase error variance, the azimuth, the number of samplings, and the signal length of the received signal in this section are output to the position calculation section 307.

The position calculation unit 307 is a signal length threshold processing unit 3
A minimum value of the phase error variance value is detected based on the phase error variance value, the direction, the number of times of sampling, and the signal length of the signal in the target signal section output from 06. Further, the sampling number and the azimuth corresponding to the minimum value of the phase error variance are extracted, the distance is calculated from the sampling number, and the azimuth is corrected for the azimuth. After the above processing, the position calculator 307 outputs the target azimuth, the distance, and the minimum value of the phase error variance to the target detector 4.

Next, in the signal detection processing of the Doppler analysis system, the reverberation processing unit 308 uses the FFT 209 shown in FIG.
, The received signal spectrum and the received signal beam direction for each time are sequentially input, and the spectrum of the reverberation band is removed by a band rejection filter having a characteristic that the band changes with time over the transmission frequency.

The peak detecting section 309 includes a reverberation processing section 308
, The maximum value of the spectrum is detected from the spectrum of the received signal for each sampling time output one after another.
The Doppler threshold processing section 310 performs threshold processing on the spectrum level based on the spectrum of the received signal for each sampling time output from the peak detection section 309 one after another.

The signal length threshold processing section 311 uses the spectrum of the received signal for each sampling time, which is thresholded by the Doppler threshold processing section 310 and is output one after another.
Calculate the length of the signal which seems to be the target exceeding the threshold. Further, the signal threshold processing unit 311 performs threshold processing on the calculated signal length with a minimum value and a maximum value of a target length range that can be arbitrarily set in advance according to use conditions and the like. If the signal length is within this range, the signal section is set as a target signal section, and the spectrum (frequency, frequency,
The spectrum level), the beam direction, and the number of times of sampling are output to the frequency variation threshold processing unit 312.

Based on the spectrum (frequency, spectrum level), beam direction, and sampling frequency of the target signal output from the signal length threshold processing unit 311, the frequency variation threshold processing unit 312 A frequency is extracted and threshold processing is performed on the absolute value of the difference between the two frequencies. 313.

The position calculator 313 detects the maximum value of the spectrum based on the spectrum (frequency, spectrum level) of the target signal, the beam direction, and the number of times of sampling. Furthermore, the frequency corresponding to the maximum value of this spectrum,
The sampling number and the beam direction are extracted, the Doppler deviation is calculated from the frequency, the distance is calculated from the sampling number, and the beam direction is corrected for the direction. After the above processing, the position calculation unit 313 determines the target direction,
The distance, the maximum value of the spectrum (hereinafter, referred to as Doppler S / N), and the Doppler deviation are output to the target detection unit 4.

Next, the target detecting section 4 will be described in detail with reference to FIG.

As described above, the target detection unit 4 integrates the target signals of each of the three systems extracted by the signal detection unit 3 based on the positions of the target signals detected in each system, and integrates the signals. In addition to calculating the position, the position and the characteristic element of the target signal of each integrated system are output.

The target integration unit 401 outputs the target direction, distance, target aspect, and feature element (signal S / N, signal length) output from the position calculation unit 304 shown in FIG. Target azimuth, distance, and feature element (phase error variance), and the target azimuth, distance, and feature element (Doppler S / N, Doppler deviation) output from the position calculation unit 313. On the other hand, by using the error (distance error, azimuth error) of the detection position for each system that can be specified in advance from the use conditions and the like, the target integration gate is set for the target position (distance, azimuth) detected for each system. Distance ± distance error,
Set in the form of azimuth ± azimuth error.

Next, the target integration unit 401 searches for the presence / absence of overlap of the target integration gates set individually for each system, and searches for a plurality of target integration gates (amplitude system, phase error dispersion system,
If the Doppler analysis system overlaps even a little, the targets detected by the overlapped systems are determined to be the same target, and they are integrated. Of the output information from the target detection unit 4, the integrated detection system Is output as the target feature element.

The position detection unit 402 is detected by at least two systems integrated by the target integration unit 401,
Further, one of the systems outputs an amplitude-based target detection position, a target aspect, and an integrated target feature element of the integrated target in which one of the systems is an amplitude system.

Next, the target classifying section 5 will be described in detail with reference to FIG.

As described above, the target classifying unit 5 calculates the individual characteristic amounts of the feature elements of each system output from the target detecting unit 4 based on the calculated target aspect.
Weighting is performed with reference to the weighting table 6 created in advance, further, a certainty factor is calculated from each of the weighted feature elements, and it is determined whether the received signal is a signal from the target based on the certainty factor, The position of the target signal is output to the display unit.

The weighting section 501 outputs the position (azimuth, distance), target aspect, and feature element (eg, signal S / N, signal length, phase error variance, Doppler) for each target output from the target detection section 4. S / N and Doppler deviation) are input, each feature element is weighted for each feature element and each aspect, and the weight and target position for each feature element are output to the certainty factor calculation unit 502. The weighting for each feature element is a weighting table in which the relationship between the input feature quantity and the weight coefficient of each feature element (input: feature quantity Xi, output: weight coefficient (0 to 1)) is registered in advance for each target representative aspect. 6 is performed. Since only the target representative aspect is registered in the weighting table, when referring to the weighting table, the weighting table closest to the calculated target aspect is selected and referred to. For the feature elements not output from the target detection unit 4, the weights of the feature elements are output as 0.

The certainty calculating unit 502 includes a weighting processing unit 5
The confidence level of the target is calculated based on the target position and the weight for each feature element, which are output from step 01, and the confidence level and the target position are output to the confidence threshold processing section 503. For calculation of the target certainty factor, a two-input MYCIN OR operation, which is one of simple expert systems, is used.

In this example, as shown in FIG.
MYCIN OR four times sequentially for five input feature elements
The calculation is performed to calculate the target certainty factor.

The certainty threshold processing unit 503 receives the target position and the target certainty output from the certainty calculating unit 502 and applies a threshold determined in advance by statistical processing or the like to the target certainty. , And outputs a position or the like to the display unit with a target having a certainty factor exceeding the threshold as a target.

[0058]

As described above, according to the present invention, the aspect of a target is calculated at a detection position where each target is integrated, and each of the feature amounts of the characteristic elements of each system is integrated in advance. Weighting is performed with reference to the created weighting table for each aspect, and furthermore, certainty is calculated from each weighted feature element, so that stable target classification accuracy can always be realized. effective.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an example of a target signal detection device according to the present invention.

FIG. 2 is a block diagram illustrating a configuration of a signal processing unit illustrated in FIG. 1;

FIG. 3 is a block diagram illustrating a configuration of a signal detection unit illustrated in FIG. 1;

FIG. 4 is a diagram for describing aspect calculation in a signal detection unit shown in FIG. 3;

FIG. 5 is a diagram for describing aspect calculation in a signal detection unit shown in FIG. 3;

FIG. 6 is a diagram for describing aspect calculation in a signal detection unit shown in FIG. 3;

FIG. 7 is a diagram for explaining aspect calculation in the signal detection unit shown in FIG. 3;

FIG. 8 is a diagram for explaining aspect calculation in the signal detection unit shown in FIG. 3;

FIG. 9 is a block diagram illustrating a configuration of a target detection unit illustrated in FIG. 1;

FIG. 10 is a block diagram illustrating a configuration of a target classifying unit illustrated in FIG. 1;

[Explanation of symbols]

 Reference Signs List 1 transmitter / receiver 2 signal processing unit 3 signal detection unit 4 target detection unit 5 target classification unit 6 weighting table 201 split beam forming unit 202 band rejection filter 203 correlation operation unit 204 phase difference detection unit 205 output detection unit 206 phase error dispersion operation Unit 207 preformed beam forming unit 208 band rejection filter 209 FFT 301 amplitude threshold processing unit 302 signal length threshold processing unit 303 aspect calculation unit 304 position calculation unit 305 phase error dispersion threshold processing unit 306 signal length threshold processing unit 307 position calculation unit 308 Reverberation processing unit 309 Peak detection unit 310 Doppler threshold processing unit 311 Signal length threshold processing unit 312 Frequency variation threshold processing unit 313 Position calculation unit 401 Target integration unit 402 Position calculation unit 501 Weighting processing unit 502 Confidence calculation unit 503 Confidence Threshold Processing unit

──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Akira Kaneda 632 Edelheim 1102, Tsukui, Yokosuka City, Kanagawa Prefecture (56) References JP-A-9-145834 (JP, A) JP-A-5-87909 (JP, A) JP-A-4-134284 (JP, A) JP-A-4-1586 (JP, A) JP-A-8-220226 (JP, A) JP-A-6-102345 (JP, A) JP-A-5-52940 (JP, A) (58) Fields surveyed (Int. Cl. ⁷ , DB name) G01S 3/80-3/86 G01S 5/18-5/30 G01S ⁷ /52-7/64 G01S 15/00- 15/96

Claims (3)

(57) [Claims] 1. A target signal detecting method for transmitting a sound wave into water and detecting a received signal obtained by receiving a reverberation sound from a target, comprising the steps of: receiving the received signal; A time-series signal representing the azimuth, a time-series signal representing the phase error variance and the orientation of the received signal, and a time-series signal extracting step of extracting and outputting a time-series signal representing the spectrum and the orientation of the received signal. A first signal for inputting a time-series signal representing an amplitude value and an azimuth of the received signal and detecting a signal whose amplitude value exceeds a preset first threshold value as a signal likely to be a first target. Step, and changing the signal length of the first target-like signal to a first value in accordance with the time-series continuity of the first target-like signal.
A second step of detecting the first target signal as a first target signal if the first signal length is within a predetermined range, and calculating the first target signal if the first signal length is within a predetermined range. An arbitrary straight line is applied to the time series-direction coordinate distribution of the amplitude of the first target signal section based on the time series amplitude and direction of the section, and the amplitude value at the coordinate point of each amplitude is calculated as the mass of the mass point. A third step of obtaining a slope of a straight line in which the moment of each amplitude or the rotational moment applied to the straight line is zero, and calculating the slope as a target aspect representing a relative direction of the target; A fourth step of calculating a target detection position indicated by a direction and a distance of the target signal and a maximum value of the amplitude value; and a time series representing a phase error variance value and a direction of the reception signal. Faith A fifth step of receiving a signal whose phase error variance value is smaller than a second threshold value set in advance as a signal likely to be a second target, and a time-series continuation of the signal likely to be the second target. The signal length of the second target-like signal is calculated as a second signal length in accordance with the characteristic, and if the second signal length is within a predetermined range, the second target-like signal is converted to a second signal length. A phase error dispersion system comprising: a sixth step of detecting as a target signal; and a seventh step of calculating a target detection position indicated by an azimuth and a distance of the second target signal and a minimum value of the phase error variance value. A signal detecting step, an eighth step of inputting a time-series signal representing the spectrum of the received signal and the azimuth of the received signal and removing a reverberation signal from the spectrum of the received signal, A ninth step of extracting a maximum spectral value from the group of spectra, and a tenth step of detecting a signal whose maximum spectral value exceeds a third threshold value set in advance as a signal likely to be a third target; Calculating the signal length of the third target signal as a third signal length based on the time series continuity and the frequency continuity of the third target signal; An eleventh step of detecting the third target-like signal as a third target signal when the signal is within a predetermined range, a target detection position indicated by an azimuth and a distance of the third target signal, and the spectrum Twelfth for calculating the maximum value of the frequency and the frequency corresponding to the spectrum indicating the maximum value
A Doppler analysis signal detection step comprising: a target information calculation step of integrating the first to third target signals to calculate a target position to obtain target information; A confidence calculation step of performing a weighting based on the relative orientation of the target and calculating a confidence indicating the degree of the target likelihood of the integrated target signal based on the target information as the weighted target information. Characteristic target signal detection method. 2. The target signal detection method according to claim 1, wherein in the certainty factor calculating step, a weighting coefficient corresponding to a target aspect is registered in advance for each target position in target information of the target signal. A first sub-step in which weighting is performed with reference to the weighting table to be used as weighting target information, and a certainty factor indicating the degree of target likelihood of the integrated target signal is calculated from the weighting target information using MYCINOR operation. And a second sub-step of calculating. 3. A target signal detecting device for transmitting a sound wave into water and detecting a received signal obtained by receiving a reverberation sound from a target, comprising: a transducer for transmitting the sound wave and receiving the received signal; A signal processing unit that outputs an amplitude-based signal indicating an amplitude and a direction according to the received signal, a phase error variance-based signal indicating a phase error variance value and a direction, and a Doppler analysis system signal indicating a spectrum of the received signal. A signal which seems to be a target is extracted for each system in accordance with the amplitude system signal, the phase error variance system signal, and the Doppler analysis system signal to obtain first to third target signals, respectively, and the first to third target signals A signal detection unit that calculates and outputs a feature amount of a feature element from the section and outputs time-series data of amplitude and azimuth corresponding to the target section detected in the amplitude system; The third target signal is integrated based on the position calculated in each system to calculate an integrated position and calculate the target aspect from the time-series data of the amplitude and the azimuth corresponding to the target section, A target detection unit that outputs a position of each system, a target aspect, and a feature element of an integrated target signal of each system; and a feature amount of each of the integrated feature elements of each system based on the target aspect. Weighting is performed by referring to a predetermined weighting table for each target aspect, a certainty factor is calculated from each of the weighted feature elements, and whether the received signal is a signal from the target is determined based on the certainty factor. A target classification unit that outputs the position of the target signal to a display unit, and the target detection unit calculates the aspect of the target by using the time-series amplitude and azimuth of the first target signal section. Base Said had first
The time series of the amplitude of the target signal section of-the arbitrary moment is applied to the distribution of the azimuth coordinate, and the amplitude value at the coordinate point of each amplitude is regarded as the mass of the mass point. A target signal detecting device, wherein a slope of a straight line that becomes zero is obtained, and the slope is calculated as a target aspect representing a relative direction of the target.