A method and device for passively positioning deep-sea targets using a horizontal array

Abstract

The present invention relates to the field of underwater acoustic engineering technology, and discloses a method and device for passively locating deep-sea targets using a horizontal array. The method comprises: using a spatial power spectrum estimation method to calculate the target azimuth angle and broadband beam output sound field intensity estimation results of the sound pressure signal collected by the horizontal array; performing spectrum analysis on the broadband beam output sound field intensity on the target azimuth angle along the frequency axis to obtain the target measured multi-path arrival delay spectrum; constructing a cost function to match the target measured multi-path arrival delay spectrum with multiple relative arrival delay template values, and estimating the distance and depth of the target based on the matching results. The method utilizes the relationship between multiple arrival delays and the target distance and depth to achieve the decoupling of the target distance and depth, and gets rid of the limitation that the existing passive positioning method based on the multi-path arrival structural characteristics requires the receiving array to have the ability to estimate the pitch angle. Compared with the traditional matching field method, the constructed cost function greatly reduces the amount of calculation, which can improve the efficiency of passive target real-time positioning.

Description

Technical Field

[0001] The present invention relates to the fields of hydroacoustic engineering, marine engineering, sonar technology, and the like, and relates to a method and a device for passively positioning a deep-sea target using a horizontal array. Background Art

[0002] Deep-sea passive target positioning has always been a hot topic in the field of underwater acoustics. The traditional matching field method matches the measured sound field with the copy sound field to estimate the target distance and depth. However, the two processes of copy field sound field calculation and matching the measured field with the copy field are computationally intensive and time-consuming. In addition, the matching field method is easily affected by the mismatch of ocean environment parameters and has poor tolerance.

[0003] There is an obvious multi-path arrival structure in the deep sea sound field, and the multi-path arrival angle and the arrival delay between the multi-paths are directly related to the distance and depth of the sound source. Compared with directly matching the received sound field, matching the multi-path arrival angle, multi-path arrival delay and multi-path interference characteristics extracted from the received sound field has a clearer physical meaning. The Chinese patent application with publication number CN 111580048A "A broadband sound source depth estimation method using a single vector hydrophone", the Chinese patent application with publication number CN116699579A "A broadband target three-dimensional passive positioning method based on a deep sea vector vertical array", and the Chinese patent application with publication number CN116609725A "A narrow-band line spectrum target depth estimation method and system using a deep sea vertical array" all achieve target depth or distance estimation by matching the deep sea multi-path arrival structure, but these methods all use the arrival angle information of the multi-path path, which requires the receiving sensor or array to have the ability to estimate the pitch angle, which requires the receiving sensor to be a vector hydrophone or a vertical array. However, as a commonly used array form in the deep sea, the horizontal array does not have the ability to estimate the pitch angle, so the above methods are not applicable.

[0004] Therefore, when using a horizontal array to passively locate deep-sea targets, the existing technology has the problems of large amount of calculation and low real-time positioning efficiency. Summary of the invention

[0005] The purpose of the present invention is to overcome the defects of the prior art, and proposes a method for passively positioning a deep-sea target using a horizontal array. The present invention also discloses a device for passively positioning a deep-sea target using a horizontal array.

[0006] On the one hand, a method for passively locating a deep-sea target using a horizontal array is provided, comprising:

[0007] Step 1: Calculate the target azimuth angle of the sound pressure signal collected by the horizontal array and the sound field intensity estimation result of the broadband beam output by using the spatial power spectrum estimation method;

[0008] Step 2: Perform spectrum analysis on the broadband beam output sound field intensity at the target azimuth along the frequency axis to obtain the target measured multipath arrival delay spectrum;

[0009] Step 3: Construct a cost function to match the measured multi-path arrival delay spectrum of the target with multiple relative arrival delay template values, and estimate the distance and depth of the target based on the matching results, wherein the multiple relative arrival delay template values ​​are calculated by a sound field calculation model based on ray theory in combination with the seawater sound speed profile, and correspond to multiple paths that mainly contribute to the sound field under different assumed target sound source distances and depths, wherein the multiple paths that mainly contribute to the sound field include part or all of the four paths of seabed reflection path, seabed-sea surface reflection path, seabed-sea surface reflection path and sea surface-seabed-sea surface reflection path.

[0010] In an improved method for passively locating deep-sea targets using a horizontal array, after step 2 and before step 3, the method further includes:

[0011] The multipath arrival delay template values ​​under different assumed sound source distances and depths are interpolated into the target measured arrival delay spectrum to obtain the measured amplitude corresponding to each delay;

[0012] The step 3 specifically includes:

[0013] The measured amplitudes of multiple time delays are multiplied by the theoretical time domain amplitudes and then added to obtain the target distance and depth estimation cost function, and the distance and depth corresponding to the maximum value of the cost function are taken as the estimated values ​​of the sound source distance and depth.

[0014] In an improved method for passively locating deep-sea targets using a horizontal array, step 1 specifically includes:

[0015] The time domain signal S(n,k,t) collected by the horizontal array is transformed by fast Fourier transform to obtain the channel signal spectrum s(n,k,f l ), where n is the horizontal array element number, n = 1, 2, ..., N, N is the number of horizontal array elements, k is the signal snapshot number, k = 1, 2, ..., K, K is the total number of signal snapshots, t represents time, l = 1, 2, ..., L, l is the frequency index, L is the number of frequency points contained in the processing frequency band f1 and f L are the upper and lower bounds of the signal processing frequency band;

[0016] Using s(n,k,f l ) determines the spectrum data vector of the entire array at the kth beat and the lth frequency point as s(k,f l )=[s(1,k,f l ),s(2,k,f l ),...,s(N,k,f l )]T , the superscript T indicates transposition;

[0017] Using the conventional beamforming spatial power spectrum estimation method, the frequency f is calculated using the following formula: l The spatial power spectrum estimation B exp (θ,f l ):

[0018] B exp (θ,f l )=a H (f l ,θ)R(f l )a(f l ,θ)

[0019] Among them, θ is the target azimuth search value, which takes a value every set angle, and the value range of θ is greater than or equal to 0° and less than or equal to 360°. a(f l ,θ) is the steering vector, d n is the distance between the nth array element and the first array element in the horizontal array, R(fl) is the frequency component f l The cross-spectral density matrix of the signal spectrum estimate is Here, the superscript H represents the conjugate transpose of the matrix;

[0020] The spatial power spectrum estimation results of multiple frequency points are summed and averaged to obtain the broadband spatial power spectrum estimation average result.

[0021]

[0022] Pick The azimuth of the peak corresponding to the target is the target azimuth estimate θ s , B exp (θ s ,f l ) is the broadband beam output sound field intensity in the estimated azimuth of the target.

[0023] In an improved method for passively locating deep-sea targets using a horizontal array, step 2 specifically includes:

[0024] The broadband beam output sound field intensity is de-averaged in the frequency domain, and the de-averaged sound field intensity spectrum is obtained using the following formula:

[0025]

[0026] Among them, θ s is the target azimuth estimate, l is the frequency index, f l is the frequency at frequency index l, f1 and fL are the upper and lower bounds of the signal processing frequency band, L is the number of frequency points contained in the processing frequency band, and B exp (θ s ,f l ) is the beam output sound field intensity at the target estimated azimuth;

[0027] The inverse Fourier transform analysis method is used to analyze the sound field intensity spectrum after de-averaging. Perform double spectrum analysis to obtain the measured multipath arrival delay spectrum

[0028]

[0029] Among them, τ is the arrival delay and f is the frequency.

[0030] In an improved method for passively locating deep-sea targets using a horizontal array, the multiple paths that mainly contribute to the sound field are four paths, and the four paths correspond to six relative arrival delay template values;

[0031] The measured amplitudes of multiple time delays are multiplied by the theoretical time domain amplitudes and then added to obtain the target distance and depth estimation cost function, and the distance and depth corresponding to the maximum value of the cost function are used as the estimated values ​​of the sound source distance and depth, specifically including:

[0032] The measured amplitudes of the six time delays are compared with the amplitude template calculated by the sound field calculation model BELLHOP Multiply and add to obtain the target distance and depth estimation cost function in, and are the assumed distance and depth of the target respectively, i is the arrival delay sequence number, and its value is 1, 2, 3, 4, 5, 6, is the measured arrival delay spectrum of the target, is the multipath arrival delay template value under different assumed sound source distances and depths, is the multipath arrival amplitude template value under different assumed sound source distances and depths, is the measured amplitude corresponding to each delay obtained.

[0033] In an improved method for passively positioning deep-sea targets using a horizontal array, the depth of the deep sea is greater than or equal to 1000 m and less than or equal to 6000 m.

[0034] In an improved method for passively locating deep-sea targets using a horizontal array, the deployment depth range of the horizontal array is greater than or equal to 10 m and less than or equal to 6000 m.

[0035] On the other hand, a device based on the above-mentioned deep-sea target passive positioning method using a horizontal array is provided, comprising:

[0036] Azimuth angle and sound field intensity estimation module: used to calculate the target azimuth angle of the sound pressure signal collected by the horizontal array and the sound field intensity estimation result of the broadband beam output by using the spatial power spectrum estimation method;

[0037] A spectrum analysis module, used to perform spectrum analysis on the broadband beam output sound field intensity at the target azimuth along the frequency axis to obtain the target measured multipath arrival delay spectrum; and

[0038] A matching module is used to construct a cost function to match the target's measured multi-path arrival delay spectrum with multiple relative arrival delay template values, and estimate the target's distance and depth based on the matching result, wherein the multiple relative arrival delay values ​​are calculated by a sound field calculation model based on ray theory in combination with the seawater sound velocity profile, and correspond to multiple paths that mainly contribute to the sound field under different assumed target sound source distances and depths, wherein the multiple paths that mainly contribute to the sound field include part or all of the four paths of the seabed reflection path, the seabed-sea surface reflection path, the seabed-sea surface reflection path, and the sea surface-seabed-sea surface reflection path.

[0039] Compared with the prior art, the advantages of the present invention are:

[0040] 1. Through the sound field calculation model based on ray theory, the six arrival delays corresponding to the four paths that mainly contribute to the sound field under different assumed target sound source distances and depths are calculated. The relationship between the six arrival delays and the target distance and depth is used to achieve the decoupling of the target distance and depth, thereby getting rid of the limitation that the existing passive positioning method based on multi-path arrival structural characteristics requires the receiving sensor or receiving array to have the ability to estimate the pitch angle;

[0041] 2. A cost function is constructed to match the measured arrival delay spectrum with the arrival delay spectrum at different assumed sound source distances and depths. Compared with the traditional matching field method, this cost function greatly reduces the amount of calculation and is expected to improve the efficiency of real-time positioning of passive targets. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] Figure 1 This is one of the flow charts for passive positioning of a target using a horizontal array in Example 1;

[0043] Figure 2 This is the second flow chart of passive positioning of a target using a horizontal array in Example 1;

[0044] Figure 3 is a schematic diagram of multi-path propagation paths of target sound sources received by the horizontal array in Example 1;

[0045] Figure 4 The simulation ocean environment parameters and the target sound source and receiving array motion situation diagram in Example 1;

[0046] Figure 5 is the target position estimation process diagram in Example 1;

[0047] Figure 6 The target azimuth beam output interference fringes and arrival delay spectrum in Example 1;

[0048] Figure 7 are six multipath arrival delay template values ​​under different assumed sound source distances and depths calculated by the sound field calculation model BELLHOP in Example 1; wherein, (a) is the SBR and BR path; (b) is the SBSR and SBR path; (c) is the SBSR and BR path; (d) is the BSR and SBR path; (e) is the BSR and BR path; (f) is the SBSR and BSR path;

[0049] Figure 8 is the distance and depth estimation ambiguity map when the target distance is 31.7 km in Example 1;

[0050] Fig. 9 is the target depth and distance estimation result in Example 1;

[0051] Fig.10 It is a schematic diagram of the structure of a deep-sea target passive positioning device using a horizontal array in Example 2. DETAILED DESCRIPTION

[0052] The present invention proposes a method for passive positioning of deep-sea targets using a horizontal array. First, the target azimuth and broadband beam output sound field intensity estimation results of the sound pressure signal collected by the horizontal array are calculated using a spatial power spectrum estimation method; then, the broadband beam output sound field intensity on the target azimuth is spectrally analyzed along the frequency axis to obtain the target measured multi-path arrival delay spectrum; then, a cost function is constructed to match the target measured multi-path arrival delay spectrum with multiple relative arrival delay template values ​​calculated by the sound field calculation model, and the distance and depth of the target are estimated based on the matching results. Compared with the traditional matching field method, since only the arrival delay template value that makes the main contribution is calculated and matched, and the copy sound field is not calculated and the measured field is matched with the copy field, relatively speaking, the amount of calculation is greatly reduced, which can improve the efficiency of passive target real-time positioning. Among them, the multiple paths that make the main contribution to the sound field include part or all of the following paths: seabed reflection path, seabed-sea surface reflection path, seabed-sea surface reflection path and sea surface-seabed-sea surface reflection path. And because the target arrival angle is not used, but the multi-path arrival delay information is used, it can be used for horizontal array to locate the target. Furthermore, the present invention also provides a specific cost function, that is, firstly interpolating the multi-path arrival delay template value under different assumed sound source distances and depths into the target measured arrival delay spectrum, obtaining the measured amplitude corresponding to each delay, and then multiplying the multiple measured amplitudes of the delays with the theoretical time domain amplitudes and adding them together to obtain the target distance and depth estimation cost function, and taking the distance and depth corresponding to the maximum value of the cost function as the sound source distance and depth estimation values.

[0053] The technical solution of the present invention is described in detail below with reference to the accompanying drawings and embodiments.

[0054] Example 1

[0055] This embodiment 1 takes the simulated data of radiation signals of target sound sources in the shadow area received by a horizontal array towed by a deep-sea surface vessel as an example. Figure 1 The flow chart of passive positioning of deep-sea targets using horizontal array is given. Figure 3 A schematic diagram of the multi-path propagation path of the target sound source received by the horizontal array in the embodiment is given. Figure 3 The sound rays in are the four sound rays that mainly contribute to the received sound field, namely the bottom reflected path (BR), the surface-bottom reflected path (SBR), the bottom-surface reflected path (BSR), and the surface-bottom-surface reflected path (SBSR). The ocean environment parameters used in the simulation are as follows: Figure 4As shown in the left figure, the seawater sound velocity profile is the actual sound velocity profile of a South China Sea marine test, with a sea depth of 4300m. The target sound source speed is 5m / s, moving toward the north, and the sound source depth is 150m. The receiving array is a towed array with 256 elements and a spacing of 1m. The towing speed is 4m / s, moving toward the east, and the towed array depth is 70m. The simulation time is 60 minutes, and a total of 100 sets of data are simulated. The distance of the target relative to the receiving array increases from 10km to 32km. The situation map of the target and the receiving ship is shown in Figure 4 Right. After the horizontal array receives the sound source signal, it estimates the distance and depth of the target sound source through Fourier transform, target azimuth spectrum estimation and beam output, inverse Fourier transform, calculation of multipath arrival delay template values ​​under different assumed sound source distances and depths, and multipath arrival delay matching. Figure 1 As shown, the process is divided into the following steps:

[0056] Step 101: The horizontal array receives the time domain signal radiated by the target sound source.

[0057] Specifically, the horizontal array is placed in water to collect the time domain waveform S(n,k,t) of the target sound source radiation signal, where n=1,2,...,N is the horizontal array element number, N is the number of horizontal array elements, k is the signal snapshot number, k=1,2,...,K, K is the total number of signal snapshots, and t represents time; the sampling rate of the signal is f s , its value range is 100Hz-100kHz.

[0058] Step 102: Perform Fourier transform on the time domain signal to obtain the frequency spectrum of the received time domain signal.

[0059] Specifically, the time domain signal collected by the horizontal array is subjected to fast Fourier transform to obtain the channel signal spectrum s(n,k,f l ), l=1,2,…,L, f1 and f L are the upper and lower bounds of the signal processing frequency band, and L is the number of frequency points contained in the processing frequency band. Then, the spectrum data vector of the entire array at the kth beat and the lth frequency point is obtained as s(k,f l )=[s(1,k,f l ),s(2,k,f l ),...,s(N,k,f l )] T , where the superscript T represents the transpose of a matrix or vector.

[0060] In this embodiment, the upper and lower limits of the signal processing frequency band are 50 Hz and 700 Hz respectively.

[0061] Step 103: Perform spatial power spectrum estimation on the time domain signal received by the horizontal array to obtain the target azimuth.

[0062] Specifically, the spatial power spectrum estimation method is used to process the signal spectrum received by the horizontal array respectively to obtain the spatial power spectrum estimation result B exp (θ,f l ), θ is the target azimuth search value, θ ranges from 0° to 360°, and takes a value at a set angle interval, and the set angle interval can be greater than or equal to 0.1° and less than or equal to 2°. Taking conventional beamforming, a classic spatial power spectrum estimation method, as an example, the frequency is f l The spatial power spectrum estimation formula at is:

[0063] B exp (θ,f l )=a H (f l ,θ)R(f l )a(f l ,θ)

[0064] Among them, a(f l ,θ) is the steering vector, d n is the distance between the nth array element and the first array element in the horizontal array. R(fl) is the frequency component f l The cross-spectral density matrix (CSDM) of the signal spectrum estimation, The superscript H represents the conjugate transpose of the matrix. In this embodiment, the interval of θ is 1°.

[0065] Step 104: Utilize the multi-frequency point spatial power spectrum estimation results to obtain broadband target azimuth and beam output sound field intensity estimation results.

[0066] Specifically, the spatial power spectrum estimation results of multiple frequency points are summed and averaged to obtain the broadband spatial power spectrum estimation average result.

[0067] The broadband spatial power spectrum estimation results of this embodiment are shown in Figure 5 ,It can be seen from the figure that as the relative position of the target and the receiving array changes, The azimuth angle at the mid-peak, i.e., the estimated value of the target azimuth angle, also changes accordingly. After estimating the target azimuth angle, combined with the result of step 103, the broadband beam output sound field intensity B at the target estimated azimuth angle is obtained. exp (θ s ,f l ). Figure 6 The left figure shows the broadband beam output sound field intensity diagram, from which obvious interference fringes can be seen, and as the distance from the sound source increases, the interference fringes become sparse.

[0068] Step 105: Target azimuth θ s The broadband beam output acoustic field intensity on the target is spectrally analyzed along the frequency axis to obtain the measured multipath arrival delay spectrum of the target.

[0069] Specifically, the sound field intensity of the broadband beam output is firstly de-averaged in the frequency domain, and the de-averaged sound field intensity spectrum is obtained using the following formula:

[0070]

[0071] Then, the sound field intensity spectrum of multiple frequency points is analyzed by using spectrum analysis methods such as inverse Fourier transform and MUSIC. Perform double spectrum analysis to obtain the measured multipath arrival delay spectrum

[0072] Taking the inverse Fourier transform as an example,

[0073] Figure 6 The figure on the right shows the arrival delay spectrum estimation result. Due to the limitation of time resolution and the fact that two of the six multipath arrival delays are close, there are only four distinct arrival delay curves in the figure. At the same time, as time goes by, each multipath arrival delay gradually decreases.

[0074] Step 106: Obtain the seawater sound velocity profile of the deployment sea area by searching in the historical database or measuring on site.

[0075] Step 107: Using the sound field calculation model based on ray theory, calculate six arrival delay template values ​​corresponding to the four paths that mainly contribute to the sound field under different assumed target sound source distances and depths. in, represents the delay of the two paths SBR and BR, represents the delay of the two paths SBSR and SBR, represents the delay of the two paths SBSR and BR, Represents the delay of the BSR and SBR paths. Represents the delay of the BSR and BR paths Represents the delay of the SBSR and BSR paths. and are the assumed distance and depth of the target respectively, i is the arrival delay sequence number, and the four paths that mainly contribute to the sound field are SBR, BR, SBSR and BSR.

[0076] In this embodiment, the BELLHOP sound field calculation model is used to calculate the multipath arrival delay.

[0077] Figure 7Six multipath arrival delay template values ​​calculated by BELLHOP under different assumed sound source distances and depths are given. It can be seen that the six arrival delays are related to the sound source distance and depth.

[0078] It should be noted that the timing relationship between step 106 to step 107 and step 101 to step 105 can also be performed in sequence, that is, first perform step 101 to step 105, then perform step 106 to step 107, and then perform step 108. Figure 1 As shown. Or first perform step 106 to step 107, then perform step 101 to step 105. It can also be performed simultaneously, such as Figure 2 As shown, after simultaneous execution, step 105 is executed followed by step 108.

[0079] Step 108: Multipath arrival delay template values ​​under different assumed sound source distances and depths Interpolation to the measured arrival delay spectrum In the above example, we can obtain the measured amplitude corresponding to each delay.

[0080] Step 109: Compare the measured amplitudes corresponding to the six time delays with the amplitude template values ​​corresponding to the six time delays Multiply and add to obtain the target distance and depth estimation cost function Delay amplitude template value It can be calculated by the sound field calculation model BELLHOP. In this embodiment, the differences between the seabed reflection coefficients of the four paths can be ignored, and the sea surface reflection coefficient is approximately -1, and the six time delay amplitude template values ​​can be approximately taken as [A1, A2, A3, A4, A5, A6] ≈ [-1 -1 1 1 -1-1].

[0081] Step 110: Use the distance and depth corresponding to the maximum value of the cost function as the estimated distance and depth of the target sound source Right now

[0082] Figure 8 The target distance and depth positioning ambiguity map obtained by matching multi-path arrival delays when the target distance is 31.7 km is given, where the white square represents the actual target position and the red asterisk represents the estimated target position. It can be seen that the two are in good agreement. Fig. 9 The target distance and depth estimation results during the entire simulation are given. The red dashed line in the figure is the actual distance and depth of the target. Fig. 9 It can be seen that this method can estimate the distance and depth of the target more accurately.

[0083] The depth of the above deep sea ranges from greater than or equal to 1000m to less than or equal to 6000m.

[0084] The deployment depth range of the above horizontal array is greater than or equal to 10m and less than or equal to 6000m.

[0085] In the scheme of the embodiment of the present invention, a horizontal array configured as a receiving horizontal array is placed in water to receive the sound signal radiated by the target sound source, and the frequency domain beam output sound field of the target orientation is obtained by using a spatial power spectrum estimation method such as conventional beamforming, and then the target measured multi-path arrival delay spectrum is obtained by inverse Fourier transform. The six relative arrival delay template values ​​corresponding to the four paths that play a major role in the sound field under different assumed target sound source distances and depths are calculated by using a sound field calculation model based on ray theory, and finally a cost function is constructed to match the measured multi-path arrival delay spectrum with the six arrival delay template values ​​under different assumed target sound source distances and depths to estimate the distance and depth of the target. Starting from the multi-path arrival structural characteristics of deep-sea sound field propagation, the present invention proposes a target passive positioning method adapted for a deep-sea horizontal array, which mainly utilizes the relationship between the six arrival delays between the four paths that play an important role in the sound field and the target distance and depth to achieve target passive positioning.

[0086] Example 2

[0087] Based on the same inventive concept as that of Embodiment 1, Embodiment 2 of the present invention provides a deep-sea target passive positioning device using a horizontal array, such as Fig.10 As shown, including:

[0088] Azimuth angle and sound field intensity estimation module 1001, used to calculate the target azimuth angle and broadband beam output sound field intensity estimation results of the sound pressure signal collected by the horizontal array by using the spatial power spectrum estimation method;

[0089] The spectrum analysis module 1002 is used to perform spectrum analysis on the broadband beam output sound field intensity at the target azimuth along the frequency axis to obtain the target measured multipath arrival delay spectrum; and

[0090] The matching module 1003 is used to construct a cost function to match the target's measured multi-path arrival delay spectrum with a plurality of relative arrival delay template values, and estimate the target's distance and depth based on the matching result, wherein the plurality of relative arrival delay values ​​are calculated by a sound field calculation model based on ray theory in combination with the seawater sound velocity profile, and correspond to a plurality of paths that mainly contribute to the sound field under different assumed target sound source distances and depths, wherein the plurality of paths that mainly contribute to the sound field include part or all of the four paths of a seabed reflection path, a seabed-sea surface reflection path, a seabed-sea surface reflection path, and a sea surface-seabed-sea surface reflection path.

[0091] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit the present invention. Although the present invention is described in detail with reference to the embodiments, it should be understood by those skilled in the art that any modification or equivalent replacement of the technical solutions of the present invention does not depart from the spirit and scope of the technical solutions of the present invention and should be included in the scope of the claims of the present invention.

Claims

1. A method for passively locating deep-sea targets using a horizontal array, comprising: Step 1: Calculate the target azimuth angle of the sound pressure signal collected by the horizontal array and the sound field intensity estimation result of the broadband beam output by using the spatial power spectrum estimation method; Step 2: Perform spectrum analysis on the broadband beam output sound field intensity at the target azimuth along the frequency axis to obtain the target measured multipath arrival delay spectrum; Step 3: Construct a cost function to match the measured multi-path arrival delay spectrum of the target with a plurality of relative arrival delay template values, and estimate the distance and depth of the target based on the matching result, wherein the plurality of relative arrival delay template values ​​are calculated by combining the seawater sound velocity profile through an acoustic field calculation model based on ray theory, and correspond to a plurality of paths that mainly contribute to the acoustic field under different assumed target sound source distances and depths, wherein the plurality of paths that mainly contribute to the acoustic field include part or all of the four paths of a seabed reflection path, a seabed-sea surface reflection path, a seabed-sea surface reflection path, and a sea surface-seabed-sea surface reflection path; After step 2 and before step 3, the method further includes: The multipath arrival delay template values ​​under different assumed sound source distances and depths are interpolated into the target measured arrival delay spectrum to obtain the measured amplitude corresponding to each delay; The step 3 specifically includes: The measured amplitudes of multiple time delays are multiplied by the theoretical time domain amplitudes and then added to obtain the target distance and depth estimation cost function, and the distance and depth corresponding to the maximum value of the cost function are used as the estimated values ​​of the sound source distance and depth; The multiple paths that mainly contribute to the sound field are four paths: the seabed reflection path, the seabed-sea surface reflection path, the seabed-sea surface reflection path, and the sea surface-seabed-sea surface reflection path. The four paths correspond to six relative arrival delay template values. The measured amplitudes of multiple time delays are multiplied by the theoretical time domain amplitudes and then added to obtain the target distance and depth estimation cost function, and the distance and depth corresponding to the maximum value of the cost function are used as the estimated values ​​of the sound source distance and depth, specifically including: The measured amplitudes of the six time delays are compared with the amplitude template calculated by the sound field calculation model BELLHOP Multiply and add to obtain the target distance and depth estimation cost function in, and are the assumed distance and depth of the target respectively, i is the arrival delay sequence number, and its value is 1, 2, 3, 4, 5, 6, is the measured arrival delay spectrum of the target, is the multipath arrival delay template value under different assumed sound source distances and depths, is the multipath arrival amplitude template value under different assumed sound source distances and depths, is the measured amplitude corresponding to each delay obtained.

2. The method for passively positioning deep-sea targets using a horizontal array according to claim 1, characterized in that: The step 1 specifically includes: The time domain signal S(n,k,t) collected by the horizontal array is transformed by fast Fourier transform to obtain the channel signal spectrum s(n,k,f l ), where n is the horizontal array element number, n = 1, 2, ..., N, N is the number of horizontal array elements, k is the signal snapshot number, k = 1, 2, ..., K, K is the total number of signal snapshots, t represents time, l = 1, 2, ..., L, l is the frequency index, L is the number of frequency points contained in the processing frequency band f1 and f L are the upper and lower bounds of the signal processing frequency band; Using s(n,k,f l ) determines the spectrum data vector of the entire array at the kth beat and the lth frequency point as s(k,f l )=[s(1,k,f l ),s(2,k,f l ),...,s(N,k,f l )] T , the superscript T indicates transposition; Using the conventional beamforming spatial power spectrum estimation method, the frequency f is calculated using the following formula: l The spatial power spectrum estimation B exp (θ,f l ): B exp (θ,f l )=a H (f l ,θ)R(f l )a(f l ,i) Among them, θ is the target azimuth search value, which takes a value every set angle, and the value range of θ is greater than or equal to 0° and less than or equal to 360°. a(f l ,θ) is the steering vector, d n is the distance between the nth array element and the first array element in the horizontal array, R(f l ) is composed of a frequency component f l The cross-spectral density matrix of the signal spectrum estimate is Here, the superscript H represents the conjugate transpose of the matrix; The spatial power spectrum estimation results of multiple frequency points are summed and averaged to obtain the broadband spatial power spectrum estimation average result. Pick The azimuth of the peak corresponding to the target is the target azimuth estimate θ s , B exp (θ s ,f l ) is the broadband beam output sound field intensity in the estimated azimuth of the target.

3. The method for passively positioning deep-sea targets using a horizontal array according to claim 1, characterized in that: The step 2 specifically includes: The broadband beam output sound field intensity is de-averaged in the frequency domain, and the de-averaged sound field intensity spectrum is obtained using the following formula: Among them, θ s is the target azimuth estimate, l is the frequency index, f l is the frequency at frequency index l, f1 and f L are the upper and lower bounds of the signal processing frequency band, L is the number of frequency points contained in the processing frequency band, and B exp (θ s ,f l ) is the beam output sound field intensity at the target estimated azimuth; The inverse Fourier transform analysis method is used to analyze the sound field intensity spectrum after de-averaging. Perform double spectrum analysis to obtain the measured multipath arrival delay spectrum Among them, τ is the arrival delay and f is the frequency.

4. The method for passively locating deep-sea targets using a horizontal array according to any one of claims 1 to 3, characterized in that: The depth of the deep sea is greater than or equal to 1000m and less than or equal to 6000m.

5. The method for passively locating deep-sea targets using a horizontal array according to any one of claims 1 to 3, characterized in that: The deployment depth range of the horizontal array is greater than or equal to 10m and less than or equal to 6000m.

6. A device based on the method for passively locating deep-sea targets using a horizontal array according to claim 1, characterized in that: include: Azimuth angle and sound field intensity estimation module: used to calculate the target azimuth angle of the sound pressure signal collected by the horizontal array and the sound field intensity estimation result of the broadband beam output by using the spatial power spectrum estimation method; The spectrum analysis module is used to perform spectrum analysis on the broadband beam output sound field intensity at the target azimuth along the frequency axis to obtain the target measured multipath arrival delay spectrum; and A matching module, used for constructing a cost function to match the measured multi-path arrival delay spectrum of the target with a plurality of relative arrival delay template values, and estimating the distance and depth of the target based on the matching result, wherein the plurality of relative arrival delay values ​​are calculated by a sound field calculation model based on ray theory in combination with the seawater sound velocity profile, and correspond to a plurality of paths that mainly contribute to the sound field under different assumed target sound source distances and depths, wherein the plurality of paths that mainly contribute to the sound field include part or all of the four paths of a seabed reflection path, a seabed-sea surface reflection path, a seabed-sea surface reflection path, and a sea surface-seabed-sea surface reflection path; The spectrum analysis module is further used to interpolate the multipath arrival delay template values ​​under different assumed sound source distances and depths into the target measured arrival delay spectrum to obtain the measured amplitude corresponding to each delay; The matching module is specifically used for: The measured amplitudes of multiple time delays are multiplied by the theoretical time domain amplitudes and then added to obtain the target distance and depth estimation cost function, and the distance and depth corresponding to the maximum value of the cost function are used as the estimated values ​​of the sound source distance and depth; The multiple paths that mainly contribute to the sound field are four paths: the seabed reflection path, the seabed-sea surface reflection path, the seabed-sea surface reflection path, and the sea surface-seabed-sea surface reflection path. The four paths correspond to six relative arrival delay template values. The measured amplitudes of multiple time delays are multiplied by the theoretical time domain amplitudes and then added to obtain the target distance and depth estimation cost function, and the distance and depth corresponding to the maximum value of the cost function are used as the estimated values ​​of the sound source distance and depth, specifically including: The measured amplitudes of the six time delays are compared with the amplitude template calculated by the sound field calculation model BELLHOP Multiply and add to obtain the target distance and depth estimation cost function in, and are the assumed distance and depth of the target respectively, i is the arrival delay sequence number, and its value is 1, 2, 3, 4, 5, 6, is the measured arrival delay spectrum of the target, is the multipath arrival delay template value under different assumed sound source distances and depths, is the multipath arrival amplitude template value under different assumed sound source distances and depths, is the measured amplitude corresponding to each delay obtained.

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