JP2002071784A - Method and device for orienting track from sailing body radiant noise - Google Patents

Abstract

PROBLEM TO BE SOLVED: To orient the track of a sailing body from the radiant noise of the sailing body on the basis that the reception of the radiant noise of the sailing body of unknown synchronous absolute time by three receivers or more allows the detection of the arrival time difference of the radiant noise to each receiver. SOLUTION: The radiant noise of the sailing body is received by the three receivers S1-SN or more, and each reception signal after FFT processing is processed at a sailing noise frequency band by band pass filter processors 13-1 to 13-N and then subjected to Doppler correction. Cross-correlation processing is performed on the reception signals subjected to Doppler correction by cross-correlation at an assumed arrival time difference detector 17 on each combination of two receivers among the receivers to compute an assumed arrival time difference curve. Then variation in the location of the sailing body and variation in unknown bias are obtained at a computing unit 18 for computing variation in the location of the sailing body and variation in unknown bias. From them, the real arrival time difference of the radiant noise is detected at a detector 19 for detecting the real arrival time difference of the radiant noise. The location of the sailing body is computed at an orienting device 20 for orienting the track of the sailing body to orient the track.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for locating a track from radiated noise of a vehicle, which uses the radiation noise of the vehicle to locate the wake of the vehicle.

[0002]

2. Description of the Related Art A conventional acoustic trajectory locating apparatus is described in "Ocean Acoustics (Basic and Applied)", Japan Society of Ocean Acoustics, P209-P213 (hereinafter referred to as "Publication 1"), and Japanese Patent No. 2723866. (Hereinafter, known document 2), and the principle of both devices is called an LBL positioning system (Long Base-Line System).
The principle and the like will be described with reference to FIGS. FIG. 10 shows a configuration of a conventional technique disclosed in the known document 2.

In FIG. 8, an eye navigating underwater or above water is shown.
The position P (x, y, z) of the marked vehicle and the
Wave position S₁(x₁, y₁, z₁), S₂(x₂, y₂,
z₂), S ₃(x₃, y₃, z₃),…, S_i(x_i, y_i, z
_i) And range R₁, R₂, R₃, ..., R_iThe relationship is
It is represented by equation (1).

[0004]

(Equation 1) Here, the arrival time difference τ to each receiver from the measurement result of the pinger sound from the pinger sound transmitter attached to the craft
Is obtained, the relationship between the arrival time difference τ and the range R is expressed by the following equation (2), where W is the sound wave propagation velocity in water. R _i −R _j = τ _ij W (2) (where τ _ij is the arrival time difference between the ranges R _i and R _j ) Consider three receivers shown in FIG. 8 to solve a three-dimensional equation. The following equation (3) is obtained.

[0005]

(Equation 2) By solving this for i receivers, the range R
Is calculated.

The arrival time difference τ of the pinger sound to each receiver
Can be directly detected from the received signal of each receiver when the pinger sound is transmitted in synchronization with the absolute time. When the pinger sound is of the asynchronous system, the cross-correlation coefficient between the received signals of the respective receivers is calculated, and the range R can be detected from the arrival time difference at which the value becomes maximum. Further, the cruising depth can be obtained by transmitting the cruising body depth as a double ping interval.

FIG. 9 shows an outline of a double pinger transmitted / received signal. The symbols in the figure are described below. ts ₁ , ts
₂ , tm ₁ and tm ₂ are the absolute synchronization times of the transmission and reception times of the pingers, td ₁ is the interval between double pings, L is the transmission cycle, and δt is the time from transmission to reception. Therefore, the formula for calculating the range R is given by the following formula (4). R = δt × W (4) where δt = tm ₁ -ts ₁ (5) where tm ₁ -ts ₁ <L

[0008] Known Document 2 uses broadband noise including radiated noise of a vehicle in place of the pinger sound in the principle disclosed in Patent Document 1, and is received by receivers arranged at two different places. The present invention relates to a signal detection device that corrects the influence of the Doppler effect accompanying the movement of a sound source generated in the broadband noise. That is, a plurality of Doppler correction units that time-compress or time-expand one input signal of the signal received at the two locations at a plurality of predetermined ratios,
A plurality of cross-correlation units for respectively obtaining the cross-correlation between the outputs of the plurality of Doppler correction units and the other signal, and a maximum selection unit for selecting a maximum value from the output of each cross-correlation unit; It is assumed that it is possible to correct the effect of the Doppler effect accompanying the movement of the sound source generated in the noise.

[0009] In FIG.
The operation status of each component of the device will be described. In the figure, 1 is water
2 indicates the water surface and 3 indicates the sea floor. Navigate underwater 1 or surface 2
When the running body 4 is running, the running noise from the running body 4
Has occurred and the receiver S₁, S ₂, ..., S_NReceived by
, 5-N at a fixed level.
A / D converters 6-1 and 6-
2, ..., 6-N. A / D converters 6-1 and 6
-2, ..., 6-N, analog signals are digital signals
Signal from each two receivers as a pair.
The one digital signal obtained by the
Input to the cross-correlation calculator 8 via the
The signal is directly input to the cross-correlation calculator 8. Doppler supplement
In the positive part 7, one of the received signals received by the two receivers is reserved.
Doppler by time compression or stretching at specified ratios
The correction is performed and output to the cross-correlation calculation unit 8. Cross-correlation calculation
In part 8, one of the received waves that has been Doppler corrected by a plurality of ratios
The signal and the other directly input signal
By calculating the correlation coefficient and detecting its maximum value
The arrival time difference is determined and output to the display unit 9. Display 9 is on
From the input arrival time difference,
Position and display the result. θ = cos^-1(τW / d) (6) FIG. 11 shows a principle diagram for measuring the direction of the target sound source.
Θ in (6) indicates a plurality of receivers A and B as shown in FIG.
Azimuth angle between the arrangement direction of
Is an arrangement interval between adjacent receivers, and r = τW.
FIG. 12 shows the principle of measuring the azimuth and position of the target sound source.
And the arrangement direction of the receivers A and B, the arrival direction of the sound wave,
Azimuth θ₁, The direction of arrangement of the receivers C and D and the arrival of sound waves
Azimuth θ with incoming direction₂From the target position (source position
Position) can be obtained.

[0010]

However, the problem of the invention disclosed in the prior art document 1 is that it is necessary to attach a pinger sound transmitter to the target vehicle in advance, so that the target vehicle is limited. is there.

The problems of the invention disclosed in the known document 2 are as follows.
In the vehicle radiation noise signal measured by each receiver,
Range difference between the respective receivers from the time difference of arrival該航Hashikarada radiation noise of the radiation noise to the wave receiver S _l and receivers S ₂ of two because there is no data of the absolute synchronization emitted time ( R ₁ −R ₂ ) is obtained, but the range R, which is the distance from each receiver to the sound source, is not obtained. Further, according to the invention of the known document 2, in order to detect the azimuth of the target vehicle, the distance between each two receivers has to be determined depending on the distance to the target vehicle. Further, the trajectory locating by detecting the target azimuth from the radiating noise of a vehicle having a very wide frequency range and a complicated change in sound pressure level has a disadvantage that the accuracy is extremely low.

[0012] In view of the above, the present invention provides a method for transmitting signals to each receiver even if there is no data on the synchronous absolute time at which the radiation noise is emitted in the vehicle radiation noise signal measured by each receiver. It is possible to determine the range from the arrival time difference of the radiated noise, and thus without depending on the equipment conditions of the vehicle
It is an object of the present invention to provide a trajectory locating method and a trajectory from a radiating noise of a vehicle capable of accurately locating a trajectory of a target.

Other objects and novel features of the present invention will be clarified in embodiments described later.

[0014]

In order to achieve the above object, according to the first aspect of the present invention, a radiating noise of a vehicle is received by three or more receivers, and an interval between received reception signals is obtained. In the trajectory locating method based on the radiated noise of the vehicle, which determines the position of the sound source by taking the cross-correlation of the signals, after the bandpass filter processing of each received signal in the frequency band of the navigation noise caused by the natural vibration characteristics of the vehicle Doppler correction is performed, and for each combination of two or more of the three or more receivers, cross-correlation processing is performed on the Doppler-corrected received signal to calculate a correlation coefficient for each frequency analysis interval dt and radiate. A hypothetical arrival time difference curve with the arrival time difference at the noise measurement start time t ₀ being 0 is calculated, and using the initial i out of n sample signals of each received signal, the vehicle body position fluctuation amount and the unknown bias Find the amount of variation, The method is characterized by detecting the true radiation noise arrival time difference from the vehicle position fluctuation amount and the unknown bias fluctuation amount, calculating the position of the vehicle over the entire radiation noise measurement time, and locating the wake.

[0015] The invention of claim 2 of the present application relates to the navigation of claim 1.
In the method of locating a wake from running body radiation noise, (a) the method of (3)
Of the two or more receivers,
The vane noise frequency band caused by the natural vibration characteristics of the vehicle
Doppler corrected after Doppler filtering
Received signal X for radiation noise measurement time T_i(t) and X_jF of (t)
The FT processing signal is read and the frequency analysis interval dt
N samples (T = n × dt) subjected to inverse FFT processing
Signal_in(t) and χ_jnCross-correlation coefficient C of (t)_ijn
Is calculated, and the real part of the cross-correlation coefficient is
Divided by the maximum value of the real part of 相 対 d_ijnso
Calculating the displayed time-relative correlation coefficient signal
And (b) the relative cross-correlation coefficient △ d_ijnRead signal
The radiation noise measurement start time t₀Receiver S at_iAnd S_j
The time difference of arrival of the vehicle's radiation noise is 0, and the sample signal χ
_in(t) and χ_jnThe first relative mutual relation for (t)
Number △ d_ij1And the second relative correlation coefficient △ d_ij2Correlation of
Is calculated and the deviation width △ w_ij1And likewise,
Eye relative correlation coefficient △ d_ij2And the third relative correlation coefficient △
d_ij3The deviation width w from the correlation_ij2And △ d
_ij2And △ d_ij3The deviation width w from the correlation_{i j3},this
Sequentially, △ d_ijiAnd △ d_{iji + 1}Deviation width of w
_ijiTo the assumed arrival time difference curve τ_ij’= W
_ij(t) determining; and (c) receiving the three or more waves.
Sampled signals of each received signal measured by the detector
₁(t), χ₂(t), χ₃(t),…, χ_nInitial within (t)
Assumed arrival time difference τ obtained for i_iji’And sailing
The body moves on a straight line for a short time (t-1) to (t + 1).
Laplacian filter is applied to the position P (k)
-Based nonlinear least-squares method applied to the position fluctuation of a vehicle
And the step of obtaining the unknown bias fluctuation amount;
Navigation on the basis of the
Arbitrary setting initial position P of running body₀About Laplacia
From the position P (0) of the hull where the filter residuals are minimized
Determine P (i) and detect true arrival time difference from its value
Steps and (e) the true radiating noise of the vehicle to each receiver
Arrival time difference and position S of each receiver_N(X _N, y_N, z_N)
And the initial position P of the vehicle₀(X₀, y₀,
z₀) And the unknown bias variation △ B_ijAs 0
Range R, which is the distance between the target and the receiver _ijThree-dimensional
By solving the equation, the total radiation noise measurement time T
Determining the position P (t) of the cruising vehicle
It is characterized by:

According to a third aspect of the present invention, there is provided a navigation system for determining the position of a sound source by receiving radiation noise of a navigation body by three or more receivers and calculating a cross-correlation between the received reception signals. In a trajectory locating device based on radiated noise from a vehicle, receivers S ₁ , S ₂ ,..., _SN which receive radiated noise from a vehicle are used (where N:
A receiving circuit (5-1, 5-) which amplifies the received signal from the receiver to a certain level.
2,..., 5-N) and A / D converters (6-1, 6-2,..., 6-N) for respectively converting analog received signals from the receiving circuit into digital received signals. An FFT processor (11-1, 11) that performs FFT processing on each of the digital received signals from the A / D converter and converts them into time-frequency signals.
,..., 12-N), storage devices (12-1, 12-2,..., 12-N) for storing the time-frequency signals subjected to the FFT processing by the FFT processor, respectively. A detector (14) for detecting a running noise frequency band caused by the natural vibration characteristic, and a band for performing a band-pass filter process on the signal from the storage device in the running noise frequency band caused by the natural vehicle vibration characteristic. Pass filter processor (13-
, 13-N), a traveling vehicle speed detector (15) for detecting the speed of the traveling vehicle based on the Doppler frequency of the received signal, and the traveling vehicle speed detector. A Doppler correction calculator (16) for Doppler correcting the received signal according to the speed of the traveling vehicle, and a combination of two or more of the three or more receivers for the Doppler corrected received signal. A cross-correlation assumed arrival time difference detector (17) for performing a cross-correlation process on the Doppler-corrected received signal and calculating an assumed arrival time difference curve with the arrival time difference at the radiation noise measurement start time t0 being ₀ ; Vessel position to determine the vehicle position variation and unknown bias variation using the initial i of n sampled signals of each received signal from the assumed arrival time difference calculated by the assumed arrival time difference detector Fluctuation and not A knowledge bias variation calculator (18);
A true arrival time difference detector (19) for detecting a true radiation noise arrival time difference from the vehicle position fluctuation amount and the unknown bias fluctuation amount calculated by the navigation body position fluctuation amount and the unknown bias fluctuation amount calculator; A trajectory tracker (2) for a trajectory for a trajectory that finds the position of the trajectory over the total radiation noise measurement time from the true arrival time difference detected by the true time difference detector and locates the wake.
0), and when the sailboat sails underwater or on the water, the time difference between the received signals received by three or more receivers and the arrival time difference of the radiated noise of the sailboat to each receiver is calculated. It is characterized in that it detects and locates the position of the ship.

[0017] The invention according to claim 4 of the present application is the navigation system according to claim 3.
In a trajectory locating device from running body radiation noise,
Cross-Correlation for Cross-Correlation Processing of Error Corrected Received Signal
(A) N receivers
Based on the combination of each of the two wavers,
Bandpass fill in frequency band caused by natural vibration characteristics
Is processed by the Doppler correction calculator (16).
Received signal X of total radiation noise measurement time T corrected for puller_i
(t) and X_jRead the FFT processing signal of (t), and
Is n times (T = n × dt) inverse FFs every frequency analysis interval dt
N sample signals obtained by T processing_in(t) and χ
_jnCross-correlation coefficient C of (t)_ijnAnd calculate the cross-correlation
Divide the real part of the coefficient by the maximum value of the real part of the cross-correlation coefficient.
Relative cross-correlation coefficient △ d_ijnThe time indicated in −-relative phase
Means for calculating a relation number signal, and (b) the relative mutual phase relation
Number △ d_ijnRead the signal and start the radiation noise measurement
t₀Receiver S at_iAnd S_jTime difference of the vehicle's radiation noise
Is set to 0, and the sample signal χ_in(t) and χ_jnAbout (t)
The first relative cross-correlation coefficient △ d_ij1And the second relative
Correlation coefficient △ d_ij2Is calculated and the deviation width △ w
_ij1, And similarly, the second relative correlation coefficient △ d
_ij2And the third relative correlation coefficient △ d_ij3From the correlation of
レ width △ w_ij2And △ d_ij3And △ d_ij4Correlation of
Deviation width w_{i j3}, Sequentially, △ d_ijiAnd △ d
_{iji + 1}Deviation width of w_ijiCalculated to reach the assumption
Time difference curve τ_ij’= W_ijmeans for determining (t)
And the aircraft body position fluctuation amount and the unknown bias fluctuation amount calculator
(18) shows each of the three or more receivers measured.
N sample signals of the received signal X (t)₁(t), χ
₂(t), χ₃(t),…, χ_nFor the initial i of (t)
Time difference τ_iji’And the airframe is very small
Between (t-1) and (t + 1), a straight line was assumed to advance.
Non-linear with Laplacian filter at Vessel position P (k)
Shape variation and unknown vias by applying the shape least squares method
Means for determining the amount of change in
The output unit (19) calculates the position change amount of the vehicle
Arbitrary setting initial position P of the vehicle based on the amount of bias fluctuation₀
Sequentially, the Laplacian filter residuals are minimized.
P (i) is determined from the position P (0) of the vehicle
Means for detecting a true arrival time difference, wherein
The track locator (20) is a receiver for each of the above-mentioned radiating noises of the vehicle.
True arrival time difference and the position S of each receiver_N(X_N, y
_N, z_N) And arbitrarily set vehicle initial position P₀(X
₀, y_O, z₀) And the unknown bias variation △ B_ijTo 0
The range R, which is the distance between the target and the receiver,_ijAbout
By solving the three-dimensional equation, the total radiation noise measurement time
Equipped with means for determining the position P (t) of the vehicle over T
It is characterized by that.

The principle of a method and an apparatus for locating a track based on the radiation noise of a vehicle according to the present invention will be described below.

The definitions of the symbols used in the following description of the principle are as follows. P (k): Position of the vehicle dP (k): Positional variation of the vehicle S _i : Position of the receiver (acoustic sensor) R _i : Distance between the vehicle and the receiver f (t) : Vessel radiation noise signal x (t): Vessel radiation noise reception signal of receiver W: Underwater sound wave propagation velocity c: Underwater sound wave attenuation coefficient [dB / m] ｛x (t) =
^{_{(R i) c f (t}} )} X (t): Wataru of receivers after the Doppler correction Hashikarada radiation noise received signal X (t) ': FFT processing signals Kou Hashikarada radiation noise received signal χ (t): Sample signal of received signal X (t) Δt: Sampling rate N: Number of receivers M: Number of receiver pairs n: Number of samples of received signal dt: Frequency analysis interval of received signal T: total radiated noise measurement time C: correlation coefficient △ d: relative correlation coefficients △ _{w n:} △ _{d n} and △ _{d n + 1} correlation shift width tau: arrival time difference _{(τ = τ '+ B ij} ) τ': Assumed arrival time difference Δτ ′: Assumed arrival time difference variation B _ij : Unknown bias ΔB _ij : Unknown bias variation b (k): Laplacian filter residual F (k): Arrival residual

In the present invention, first, n sample signals _{１ 1} (t), の of the received signals X _n (t) of all the receivers are provided.
₂ (t), ..., first i (eg: i = 30) of chi _n (t) using, from the initial position _{P 0} of the domestic Hashikarada _{(k 0)} to _{P i (k i)} track And the unknown bias B are calculated.

Next, from the track including the calculated expected position P ₀ (k), the position P (i + 1) of the vehicle is determined using the arrival time difference τ in the total radiation noise measurement time. The principle will be described below according to the procedure.

(A) Receiving the radiating noise of the vehicle at time t
X (t), the signal received by the vessel S was set arbitrarily for the ship
Initial position P₀(x₀, y₀, z₀), Position S of all receivers
_i(x_i, y _i, z_i) Is set as the initial value.

Range R (t) at time t = | P (t) -S |
, The radiation noise f (t) generated by the vehicle is
+ In R (t) / W}, when the damping coefficient of the sound waves and c (dB / m), a waveform that reaches the receiving transducer becomes ^{{R (t)} c f} (t). Here, for t = t ₁ , t ₂ ,.

[0024]

(Equation 3) Becomes This waveform is again divided at the sampling rate Δt, and the received wave of the receiver is the received signal x.
(t ₁ ), x (t ₂ ), x (t ₃ ),..., x (t _n ).

(B) Received signals x _i (t) and x _j (t) are read for each combination of two of the N receivers.

(C) FFT processing is performed on the received signals x _i (t) and x _j (t) at each frequency analysis interval dt.

[0027] and (d) detecting the minimum frequency component _{f mi} n Hz and the maximum frequency component _{f max} Hz of cruising noise frequency band caused by the domestic Hashikarada natural vibration characteristics. For this detection, the configuration described in Japanese Patent Application No. 11-069924 previously proposed by the present inventors can be used.

(E) A bandpass filter process is performed on the received signal of the radiated radiated noise in the range of the minimum frequency component f _min Hz and the maximum frequency component f _max Hz caused by the cruise noise frequency band caused by the natural vibration characteristics of the vehicle. .

(F) Doppler correction is performed on the time-frequency received signal that has been subjected to each band-pass filter processing in a combination of two of the three or more receivers. For this Doppler correction, a configuration described in a known document 2 or Japanese Patent Application No. 11-069924 previously proposed by the present inventors can be used.

(G) In each combination of two or more of the three or more receivers, the time-frequency received signal X _i (t) of each of the two Doppler corrected receivers S _i and S _j ) 'And X
_j (t) ′ is subjected to inverse FFT processing to calculate a cross-correlation coefficient C _ij between X _i (t) and X _j (t).

[0031]

(Equation 4) Further, C _ij ′ is subjected to inverse FFT processing to perform cross-correlation coefficient C
_ij is calculated.

(H) In order to express the cross-correlation coefficient as a relative value, △ d _ij is obtained. Δd = real (C) / real (C _max ) (9) where real (C _max ) is the maximum value of the real part of C _n (t) real (C) is the real part of C _n (t)

[0033] (i) track locating method and apparatus from domestic Hashikarada radiation noise is present invention, the measurement starting absolute time t ₀ on the received signals of the receivers since it is assumed that the trigger function no Since it is unknown, the initial position P ₀ of the hull becomes an unknown number. Accordingly, the unknown initial values arbitrarily assumed initial position P ₀ of the domestic Hashikarada.

(J) First, the assumed arrival time difference τ 'is calculated
You. The calculation method will be described below. The relative cross-correlation coefficient △
d_ijnThe signal is read and the radiation noise measurement start time t ₀
Receiver S at_iAnd S_jThe arrival time difference of the vehicle's radiation noise
And the sample signal χ _in(t) and χ_jnAbout (t) 1
Th relative cross-correlation coefficient △ d_ij1And the second relative correlation
Coefficient △ d_ij2Is calculated and the deviation width △ w_ij1
, And similarly, the second relative correlation coefficient △ d_ij2And 3
Th relative correlation coefficient △ d_ij3The deviation width w from the correlation
_ij2And △ d_ij3And △ d_ij4Deviation from correlation
Width w_{ij 3}, Sequentially, △ d_ijiAnd △ d
_{iji + 1}Deviation width of w_ijiCalculated to reach the assumption
Time difference curve τ_ij’= W_ij(t) is required.

[0035] (k) will be described with the assumption arrival time difference tau 'below how to determine the range R _i. Assumption time difference τ
_ij ′ is obtained for N (N−1) / 2 sensor pairs M _ij . Here, by adding an unknown bias B _ij to the assumed arrival time difference τ _ij ′ at time t on the received signal, the following equation is established.

[0036]

(Equation 5) Here, B _ij is a constant that does not depend on t. This is rewritten as t = kdt. | P _i (k) −S _i | − | P _j (k) −S _j | = τ _ij ′ (k) + B _ij (11)

In the radiation noise measurement range of the present invention, the position P (k) on the course of the cruising vehicle is set at a short time (t-1)
The following equation is established while the Laplacian filter residual is b (k) during (t + 1). α {P (k−1) −2P (k) + P (k + 1)} = b (k) (12) A simultaneous equation is obtained for k = 1, 2,..., n in equations (11) and (12). Stand up and solve. Here, the number of unknowns P (k) and _{B ij} is the _3n + N _{C 2,} the number of _{equations, N C 2 · n + 3} (n-
2). When N = 3, the number of unknowns is 3n + 3,
The number of equations is 3n + 3 (n-2). Therefore, if n ≧ 3, the number of equations ≧ the number of unknowns, and the unknowns are apparent from equations (11) and (12).

When N = 4, the number of unknowns is
With 3n + 6, the number of equations is 6n + 3 (n-2). When n is large, the following equation can be defined from equation (10). F (k) = | R _i (k) | − | R _j (k) | −τ _ij ′ (k) −B _ij (13) Here, F (k) is an arrival time residual.

(L) Calculate the position variation dP (k) of the marine vehicle and the unknown bias variation △ B _ij . The method will be described below. Equation (12) is rewritten into the following equation. X (k) = α {x (k−1) −2x (k) + x (k + 1)} Y (k) = α {y (k−1) −2y (k) + y (k + 1)} (14) Z (k) = α {z (k−1) −2z (k) + z (k + 1)} Equation (14) is totally differentiated. dX (k) = αdx (k−1) −2αdx (k) + αdx (k + 1) dY (k) = αdy (k−1) −2αdy (k) + αdy (k + 1) (15) dZ (k) = αdz (k-1) -2αdz (k) + αdz (k + 1) When the equation (15) is fully differentiated, the assumed arrival time difference τ ′ is eliminated and the following equation is obtained.

[0040]

(Equation 6) dF (k) = {(x -x i) / R i - (x-x j) / R j} dx (k) + {(y-y i) / R i - (y-y j) / R _{j} dy (k) + {} (z-z i) / R i - (z-z j) / R j} dz (k) - △ B ij (17) Here, equations (15) and (17) are made simultaneous, and dx (k), dy (k), dz (k) and △ B _ij are determined by the least squares method.

(M) Determine the position P (i) of the vehicle. Dx (k), d obtained in the processing of the above items (a) to (h)
Based on y (k), dz (k) and △ B _ij , the initial position P ₀ is sequentially updated from equation (18) from the position P (0) of the hull where the obtained residual is minimized. Determine P (i). _{x (k n) = x (} k n) + dx (k n) y (k n) = y (k n) + dy (k n) ... (18) z (k n) = z (k n) + dz (k _n )

(N) Determine the position P (i + 1) of the running body.
Obtained initial position P of the vehicle₀(x₀, y₀, z₀) And true
△ B from arrival time difference τ _ij= 0 and at time t
The position P (t) of the vehicle is determined.

The processing method will be described below. Aircraft position P
Initial value P (i + 1) = 2P (i) -P converged to (x, y, z)
(i-1).

Next, the following equation is obtained from equations (17) and (18). dF (k) = A _ij dx + B _ij dy + C _ij dz (19) where A _ij = (x−x _i ) / R _i − (x−x _j ) / R _j B _ij = (y−y _i ) / R _i − (y−y _j ) / R _j C _ij = (z−z _i ) / R _i − (z−z _j ) / R _j (19) is expressed by a matrix.

[0045]

(Equation 7) This is F = M · dP.

[0046]

(Equation 8) In order to obtain dP from equation (23), a transposed matrix ^t M is applied to both sides. ^t MF ^{= t} MMdP than ^{dP = (t MM) -1 (} t MF) ... (24)

(O) Mean square residual (ΣdF (k) ² /
S _ij ) ^計算 is calculated.

(P) If the residual is not different from the previous residual, the process ends.

(Q) A matrix M of the following equation is calculated.

[0050]

(Equation 9)

(R) Calculate dP = ( ^t MM) ⁻¹ ( ^t MF)

(S) _Let P (k _n ) = P (k _n ) + dP (k _n ).

(T) Return to item (n).

(U) If the residual is not different from the previous residual, the process ends.

[0055]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a method and apparatus for locating a track from radiation noise of a vehicle according to the present invention will be described below with reference to the drawings.

FIG. 1 shows a configuration of an embodiment of a method and an apparatus for locating a track from a radiating noise of a vehicle according to the present invention.

In this figure, 1 is underwater, 2 is water surface, 3
Seabed, is 4 _{Kohashikarada, S 1, S 2, ...} , S N is wave receiver (acoustic sensor), 5-1,5-2, ..., 5- N are the receiving circuit, 6-1,6 −2,..., 6-N are A / D converters, 1
.., 11-N are FFT processors, 12
-1, 12-2,..., 12-N are storage devices, 13-1,
13-2,..., 13-N are band-pass filter processors, 14 is a navigation noise frequency band detector caused by the natural vibration characteristics of the vehicle, 15 is a vehicle speed detector based on Doppler frequency, and 16 is Doppler A correction arithmetic unit, 17 is a hypothetical arrival time difference detector based on cross-correlation, 18 is a vehicle position fluctuation amount and unknown bias fluctuation amount calculation unit, 19 is a true arrival time difference detector, and 20 is a cruise vehicle trajectory locator. is there. Note that N is an integer of 3 or more.

The receivers S ₁ , S ₂ ,..., _SN detect the radiation noise of the vehicle 4 traveling on the water surface or underwater, and are acoustic sensors such as hydrophones, for example.

The receiving circuit 5-1,5-2, ..., 5-N are receiving transducer _{S 1, S 2, ...,} after each amplitude amplifying the received signal input from the _{S N} to a certain level, A / D converter 6
-1, 6-2, ..., 6-N.

A / D converters 6-1, 6-2,..., 6-N
Converts the analog received signals transferred from the receiving circuits 5-1, 5-2,..., 5-N into digital received signals, and converts the digital received signals into FFT processors 11-1 and 11-1.
−2,..., 11-N.

[0061] receivers in Figure 2 _{S 1} and wave receiver _{S 2} and receivers S
₃ shows an example of a received signal by No. ₃ .

The FFT processors 11-1, 11-2,..., 1
1-N performs an FFT process on the digital received signal every dt seconds, converts the digital received signal into a time-frequency signal, and
2-2,..., 12-N.

Vessel-specific vibration characteristics (Vessel-specific frequency)
., 12-N from the storage devices 12-1, 12-2,..., 12-N, individually fetch the received signals converted into time-frequency signals into the detector 14. , The upper limit and the lower limit of the running noise frequency band caused by the natural vibration characteristics of the vehicle, and outputs the detected values to the band-pass filter processors 13-1, 13-2,..., 13-N.

The processing in this case is described in Japanese Patent Application No. 11-069924.
No. configuration can be used. That is, the running noise frequency band detector 14 caused by the natural vibration characteristic of the vehicle is configured to calculate the time obtained by performing the FFT processing from the storage device based on the received signal from the _first receiver (for example, S ₁ ). Means for reading a received frequency signal and creating a loafgram for each predetermined sampling time; means for extracting a maximum value sequence of power values in a spectrum line between 0 and FHz in the loafgram; Means for performing the entirety of the maximum value sequence of the power values of the traveling noise in the range of the frequency 0 to FHz in the loafgram, the signal received by the second receiver (for example, S ₂ ) And the upper and lower limits of the navigation noise frequency band detected based on the received signal of the first receiver are determined. When the upper limit value and the lower limit value of the navigation noise frequency band detected based on the reception signal of the second receiver are matched, the frequency band of the navigation noise caused by the navigation body vibration characteristics is And a determination unit. Here, the above-mentioned and the above-mentioned means are performed for each of the three or more receivers to determine whether the upper limit and the lower limit of the navigation noise frequency band detected for each receiver match each other. The determination may be made.

The band-pass filter processors 13-1, 1
3-2,..., 13-N denote ranges of the upper limit value and the lower limit value of the frequency band inputted from the navigation noise frequency band detector 16 caused by the natural vibration characteristic of the vehicle, and the storage devices 12-1 and 12-12.
,..., 12-N, performs band-pass filter processing on the received signal and performs Doppler correction
Transfer to

FIG. 3 shows receivers S ₁ and S ₂ that have been subjected to band-pass filter processing in the range of the upper limit and the lower limit of the running noise frequency band caused by the natural frequency of the vehicle. shows the received signal by instrumental _{S 3.}

The Doppler correction computing unit 16 performs Doppler correction on the received signal and outputs the signal to the assumed arrival time difference detector 17 based on cross-correlation in order to eliminate the influence of the Doppler phenomenon in the track location. The processing for removing the influence of the Doppler phenomenon is disclosed in the known document 2 and Japanese Patent Application No. 11-6 proposed by the present inventors.
The technique described in No. 9924 can be used. In other words, based on the detection result of the vehicle speed by the Doppler frequency of the vehicle speed detector 15 that detects the speed of the vehicle by the Doppler frequency from the received signal, the Doppler correction calculator 16 performs time expansion and contraction by the Doppler phenomenon. The Doppler correction of the received signal is performed by obtaining the rate.
In the present embodiment, the navigation body speed detector 15 detects the speed of the navigation body by receiving the output of the navigation noise frequency band detector 14 caused by the navigation body natural vibration characteristic. However, the speed of the vehicle may be detected based on the Doppler frequency from the received signal that has been subjected to the band pass filter processing.

FIG. 4 is an explanatory diagram of Doppler-corrected reception signals X ₁ (t) and X ₂ (t) of radiation noise by the receivers S ₁ and S ₂ .

Cross-correlation of Doppler-corrected received signal
Assumed arrival time difference detector 17 based on cross-correlation for processing
Is based on (a) a combination of two of the N receivers.
In the frequency range attributable to the characteristic characteristics of the vehicle.
Doppler corrected after band pass filtering
Signal X of total radiation noise measurement time T_i(t) and X_j(t)
Of the FFT processing signal of
Determined by performing inverse FFT processing n times (T = n × dt) for each interval dt
n sample signals_in(t) and χ_jnCross-correlation of (t)
Coefficient C_ijnAnd calculate the real part of the correlation coefficient as the phase relationship
Divided by the maximum value of the real part of the number, the relative cross-correlation coefficient △ d_ijn
Means for calculating a time-relative correlation coefficient signal indicated by:
(b) the relative cross-correlation coefficient △ d_ijnRead signal
And the radiation noise measurement start time t₀Receiver S at_iAnd S_jof
Assuming that the difference in arrival time of the radiating noise of the vehicle is 0, the sample signal χ
_in(t) and χ_jnThe first relative mutual relation for (t)
Number △ d_ij1And the second relative correlation coefficient △ d_ij2Correlation of
Is calculated and the deviation width △ w_ij1And likewise,
Eye relative correlation coefficient △ d_ij2And the third relative correlation coefficient △
d_ij3The deviation width w from the correlation_ij2And △ d
_ij3And △ d_ij4Deviation from the correlation of △ wd _ij3This
順次 d_ijiAnd △ d_{iji + 1}Deviation width of w
_ijiTo the assumed arrival time difference curve τ_ij’= W
_ij(t). For example, i = 1,
If j = 2, hypothetical arrival time difference detector based on cross-correlation
At 17, the Doppler correction calculator 16 corrects
Received signal X₁(t) and X₂(t) of the cross-correlation coefficient
The maximum value is calculated, and the assumed arrival time difference at that time is obtained.

FIG. 5 shows the assumption arrival time difference detection based on the cross-correlation.
The receiver S by the receiver 17_lAnd receiver S ₂Received by
Received signal X₁(t) and X₂Assumption (t) between receivers
The result of obtaining the time difference curve is shown.

Based on the assumed arrival time difference calculated by the assumed arrival time difference detector 17, the n-th sample signal of each received signal is used to calculate the initial i To determine the position variation of the vehicle and the unknown bias variation. In other words, the vehicle body position fluctuation amount and unknown bias fluctuation amount calculator 18 calculates n sample signals の of each received signal X (t) measured by three or more receivers.
₁ (t), χ ₂ (t), _{３ 3} (t),..., _{Ｎ n} (t), the assumed arrival time difference τ _iji 'obtained for the initial A means is provided for calculating the position fluctuation amount and the unknown bias fluctuation amount of the vehicle by applying the nonlinear least squares method using the Laplacian filter to the vehicle position P (k) which is assumed to travel on a straight line from 1) to (t + 1). I do.

FIG. 6 shows receivers S ₁ , S ₂ , S
Assuming the difference between the arrival times of the true radiation noise arrival time difference and the wave receiver S _l and S ₂ between ₃ and showing the relationship between the unknown bias.

The true arrival time difference detector 19 successively minimizes the Laplacian filter residual for an arbitrary initial value P ₀ of the vehicle based on the obtained vehicle position variation and unknown bias variation. From the position P (0) to P (i)
And a means for detecting a true arrival time difference from the value.

The trajectory track finder 20 is adapted to detect the true arrival
Each receiver of the vehicle radiation noise detected by the difference detector 19
True arrival time difference and the position S of each receiver_i(x_i,
y_i, z _i) And the arbitrarily set vehicle initial position P₀(x
₀, y₀, z₀) And the unknown bias variation △ B_ijTo 0
As the range R, which is the distance between the target and the receiver.
By solving the dimensional equation, the total radiation noise measurement time T
Means for determining the position P (t) of the
This allows the vehicle to maintain its
Find the position and locate the wake.

FIG. 7 shows the arbitrarily set initial position P _{0, the} predicted orientation track and the optimal predicted orientation trajectory of the vehicle.

Although the embodiments of the present invention have been described above, it is obvious to those skilled in the art that the present invention is not limited to the embodiments and various modifications and changes can be made within the scope of the claims. There will be.

[0077]

As described above, according to the present invention, the radiating noise of the vehicle is received by three or more receivers, and the cross-correlation between the received signals is obtained, so that the target navigation In the positioning method and apparatus for determining the track of a body, two or more receivers are included in the vehicle radiation noise signal measured by each receiver according to the present invention, even if there is no data on the synchronous absolute time at which the radiation noise was emitted. Since the range R _i can be obtained from the arrival time difference of the radiating noise of the vehicle to the wave receiver S _i and the receiver S _j , the target track can be accurately determined without depending on the equipment conditions of the vehicle. Can be oriented.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an embodiment of a method and an apparatus for locating a track from a vehicle radiation noise according to the present invention.

FIG. 2 is a waveform diagram showing an example of a vehicle radiation noise reception signal detected by a receiver S ₁ , a receiver S ₂ , and a receiver S ₃ .

[Figure 3] Kou Hashikarada unique due to the vibration characteristics of sailing noise frequency band upper limit value and the wave receiver was carried out bandpass filtering in a range of lower values S ₁ and wave receiver S ₂ and receivers S FIG. 6 is a waveform diagram illustrating an example of a received signal of No. ₃ ;

Is an illustration of a Doppler compensation received signals of radiation noise due to [4] wave receiver S _l and S _2.

FIG. 5 is an explanatory diagram showing an example of a result of detection of an assumed arrival time difference curve based on cross-correlation.

6 is an explanatory diagram showing an example of the result of obtaining the radiation noise arrival time difference and the wave receiver S ₁ and assume the arrival time difference and the unknown bias of S ₂ for each two of the three receivers.

FIG. 7 is an explanatory diagram showing an example of an arbitrary set initial position, a predicted orientation track, and an optimal predicted orientation detection result of a target marine vehicle.

FIG. 8 is an explanatory diagram of a track body locating method using a pinger sound.

FIG. 9 is a diagram illustrating a relationship between a transmitted signal and a received signal of a pinger sound.

FIG. 10 is a block diagram showing a configuration of a conventional technique disclosed in a known document 2.

FIG. 11 is a diagram illustrating the principle of detecting the direction of a target sound source.

FIG. 12 is a diagram illustrating the principle of position measurement of a target sound source by a plurality of receivers.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Underwater 2 Water surface 3 Sea bottom 4 Aircraft 5-1, 5-2, ..., 5-N Receiver circuit 6-1, 6-2, ..., 6-NA / D converter, 11-1, 11- 2,..., 11-N FFT processor 12-1, 12-2,..., 12-N storage device 13-1, 13-2,. Navigational Frequency Band Detector Due to Aircraft 15 Vessel Velocity Detector Based on Doppler Frequency 16 Doppler Correction Calculator 17 Assumed Arrival Time Difference Detector Based on Cross-Correlation 18 Vessel Vehicle Position Variation and Unknown Bias Variation Calculator 19 True , Arrival time difference detector 20 Track body locator S ₁ , S ₂ , ..., _SN receiver

Claims (4)

[Claims] 1. A wake from a radiating noise of a vehicle in which the radiation noise of the vehicle is received by three or more receivers and the position of a sound source is obtained by cross-correlating the received signals. In the orientation method, each received signal is band-pass filtered in the navigation noise frequency band caused by the natural vibration characteristics of the vehicle, Doppler corrected, and a combination of two or more of three or more receivers is used. For each of the Doppler-corrected received signals, cross-correlation processing is performed, a correlation coefficient is calculated for each frequency analysis interval dt, and an assumed arrival time difference curve is calculated with the arrival time difference at the radiation noise measurement start time t0 being ₀ . Calculating the vehicle position fluctuation amount and the unknown bias fluctuation amount by using the initial i signals among the n sample signals of each received signal, and obtaining a true value from the vehicle position fluctuation amount and the unknown bias fluctuation amount Radiation noise arrival time difference Detect, track locating method from domestic Hashikarada radiation noise, characterized by locating a track by calculating the position of the domestic Hashikarada over the entire radiation noise measurement time. 2. The navigation from the vehicle radiation noise according to claim 1.
In the mark locating method, (a) among the three or more receivers,
In the combination of each two units, the characteristic
Bandpass filtering in the contributing navigation noise frequency band
Of the total radiation noise measurement time T after Doppler correction
Received signal X_i(t) and X_jRead the FFT processing signal of (t)
Therefore, n times (T = n × d
t) n sample signals subjected to inverse FFT processing_in(t) and
χ_jnCross-correlation coefficient C of (t)_ijnAnd calculate the mutual phase
The real part of the relation number is the maximum value of the real part of the cross-correlation coefficient.
Divided relative cross-correlation coefficient △ d_ijnTime-relative
Calculating a correlation coefficient signal; and (b) calculating the relative mutual
Correlation coefficient △ d_ijnRead the signal and start measuring radiation noise.
Start time t₀Receiver S at_iAnd S_jAircraft's radiation noise arrival
The time difference is set to 0, and the sample signal χ_in(t) and χ_jn(t)
For the first relative cross-correlation coefficient △ d_ij1And the second
Relative correlation coefficient △ d_ij2Calculate the correlation of
△ w_ij1, And similarly, the second relative correlation coefficient △ d
_ij2And the third relative correlation coefficient △ d_ij3From the correlation of
レ width △ w_ij2And △ d_ij2And △ d_ij3Correlation of
Deviation width w_{i j3}, Sequentially, △ d_ijiAnd △ d
_{iji + 1}Deviation width of w_ijiCalculated to reach the assumption
Time difference curve τ_ij’= W_ijdetermining (t);
(c) Each received signal measured by the three or more receivers
N sample signals χ ₁(t), χ₂(t), χ₃(t),
…, Χ_nAssumption reached for the initial i of (t)
Time difference τ_iji’And the vehicle is from the minute time (t-1)
Vessel position P assumed to travel on a straight line during (t + 1)
(k) Non-linear least squares method using Laplacian filter
To calculate the position fluctuation and unknown bias fluctuation of the hull.
And (d) determining the amount of change in the position of the
Arbitrary setting initial position P of the craft based on the amount of knowledge bias fluctuation
₀Sequentially, minimize the Laplacian filter residuals
P (i) is determined from the position P (0) of
(E) detecting the true arrival time difference from the
True arrival time difference of radiation noise to each receiver and the position of each receiver
Place S_N(X _N, y_N, z_N) And arbitrarily set airframe
Initial position P₀(X₀, y₀, z₀) And from unknown bias fluctuation
Quantity △ B_ijWith 0 as the distance between the target and the receiver
Di R _ijBy solving the three-dimensional equation
Determining the position P (t) of the vehicle over the shooting noise measurement time T
Vehicle radiation characteristic characterized by the following steps:
Track location method from sound. 3. A radiating noise from a hull vehicle which determines a position of a sound source by receiving radiation noise of the hull vehicle by three or more receivers and calculating a cross-correlation between the received signals. In the track locating device, receivers S ₁ , S ₂ ,..., S for receiving radiation noise of a vehicle
_N (where N: an integer of 3 or more) and a receiving circuit (5-1, 5-2,..., 5-N) for amplifying the received signal from the receiver to a certain level.
A / D converters (6-1, 6-2, and 6-1) for converting analog received signals from the receiving circuit into digital received signals, respectively.
, 6-N), and the digital received signal from the A / D converter is
An FFT processor (11-1, 11-2,..., 11-N) that performs FT processing and converts the time-frequency signal into a time-frequency signal, and a storage device that stores the time-frequency signal subjected to the FFT processing by the FFT processor ( 12-1, 12-2,
, 12-N), a detector (14) for detecting a navigation noise frequency band caused by the natural vibration characteristic of the vehicle, and the storage device having a navigation noise frequency band caused by the natural vibration characteristic of the vehicle. Band-pass filter processing unit (13-1, 13-2,
..., 13-N), a vehicle speed detector (15) for detecting the speed of the vehicle based on the Doppler frequency of the received signal, and the speed of the vehicle detected by the vehicle speed detector A Doppler correction arithmetic unit (16) for performing Doppler correction on the received signal according to (1). The Doppler corrected received signal is subjected to the Doppler correction for each combination of two or more of the three or more receivers. A cross-correlation hypothesis arrival time difference detector (17) for performing cross-correlation processing on the received signal and calculating a hypothesis arrival time difference curve with the arrival time difference at the radiation noise measurement start time t0 being ₀ ; A vehicle position variation and an unknown bias are obtained from the calculated assumed arrival time difference by using an initial i number of n sample signals of each received signal to determine a vehicle position variation and an unknown bias variation. Momentum calculator (1
8); a true arrival time difference detector for detecting a true radiation noise arrival time difference from the navigation body position fluctuation amount and the unknown bias fluctuation amount calculated by the navigation body position fluctuation amount and the unknown bias fluctuation amount calculator ( 19), and a trajectory tracker (20) for a trajectory that finds the position of the trajectory over the total radiation noise measurement time from the true arrival time difference detected by the true arrival time difference detector and locates the wake. When the navigation system is moving underwater or above the water, the difference in the arrival time of each vehicle's radiated noise to each receiver is detected from the received signals received by three or more receivers, A trajectory locating device for radiating noise of a vehicle, characterized by locating a vehicle. 4. Navigating from the vehicle radiation noise according to claim 3.
In the mark locating device, the Doppler-corrected received signal
Assumption Time Difference Due to Cross-Correlation Performing Cross-Correlation Processing of Signals
The detector (17) is (a) a set of two of each of the N receivers.
On the basis of the combination, the
After the band pass filter processing in the
All emission corrected by Doppler correction by the puller correction calculator (16)
Received signal X for radiation noise measurement time T_i(t) and X_jFF of (t)
T processing signal is read, and the signal is subjected to frequency analysis interval dt.
N pieces obtained by performing inverse FFT processing n times (T = n × dt) for each time
The sample signal of_in(t) and χ _jnCross-correlation coefficient of (t)
C_ijnAnd calculate the real part of the cross-correlation coefficient
Relative cross-correlation coefficient △ d divided by the maximum value of the real part of the correlation coefficient
_ijnFor calculating the time-relative correlation coefficient signal indicated by
And (b) the relative cross-correlation coefficient △ d_ijnRead the signal
And the radiation noise measurement start time t₀Receiver S at_iAnd S
_jAnd the sample signal
χ_in(t) and χ_jnFirst relative cross-correlation for (t)
Coefficient △ d_ij1And the second relative correlation coefficient △ d_ij2Phase of
Calculate Seki, and its deviation width △ w_ij1And similarly, 2
Th relative correlation coefficient △ d_ij2And the third relative correlation coefficient
△ d_ij3The deviation width w from the correlation_ij2And △ d
_ij3And △ d_ij4The deviation width w from the correlation_{i j3},this
Sequentially, △ d_ijiAnd △ d_{iji + 1}Deviation width of w
_ijiTo the assumed arrival time difference curve τ_ij’= W
_ijmeans for calculating (t), wherein the vehicle body position fluctuation amount and the unknown bias fluctuation amount calculator (1)
8) shows each of the received waves measured by the three or more receivers.
N sample signals of the signal X (t)₁(t), χ ₂(t),
χ₃(t),…, χ_nfor the initial i of (t)
Assumed arrival time difference τ_iji′ And the vehicle for a very short time (t-
Vessel that travels on a straight line from 1) to (t + 1)
Non-linear minimum by Laplacian filter at position P (k)
Positional variation and unknown bias variation of the vehicle using the square method
Means for determining the quantity, wherein the true time difference of arrival detector (19) is
Based on the vehicle position fluctuation amount and the unknown bias fluctuation amount,
Arbitrary setting initial position P₀Laplacian filter
From the position P (0) to P (i) of the hull where the Luther residual is minimized
To determine the true arrival time difference from that value.
The trajectory locator (20) of the hull is provided with:
True arrival time difference of sound to each receiver and position S of each receiver
_N(X_N, y_N, z_N) And arbitrarily set vehicle initial position
Place P₀(X₀, y_O, z₀) And the amount of unknown bias fluctuation △
B_ijIs set to 0, the range R which is the distance between the target and the receiver
_ijBy solving the three-dimensional equation for
Hand that determines the position P (t) of the hull over the sound measurement time T
Navigation from radiating noise of a vehicle characterized by having a step
Mark location device.