RU2316015C1 - Method for computer-interferometer localization of complex signals - Google Patents

Abstract

FIELD: measuring equipment engineering, possible use in radio engineering for passive detection and space-frequency-time localization of complicated signals.

SUBSTANCE: increased efficiency is achieved due to additional information extracted from two-dimensional time-frequency discrepancy function, which is formed and transformed to function of mutual spectral density for each expected arrival direction for signals, coherently received by two spatially distanced channels.

EFFECT: increased efficiency of localization of several complicated signals with a priori unknown form and frequency-time structure in broad sector of angles.

5 cl, 17 dwg

Description

The invention relates to measuring equipment and can be used in radio engineering for passive detection and spatial-frequency-time localization of energy of complex signals under conditions of a priori uncertainty regarding the properties and parameters of signals, noise and interference.

Solving the problem of detecting and localizing the frequency, time and direction of arrival of a continuously increasing number and types of complex signals (single-frequency noise-like signals (SHPS), multi-frequency signals with frequency hopping (WMS), signals with linear frequency modulation (LFM), and combinations thereof), having a low spectral power density and designed to ensure the operation of several transmitters in the same frequency band, is an essential condition for ensuring the effectiveness of a wide fleet of existing x and promising radio systems.

A known method of computer-interferometric localization of complex signals [1], in which digital signals characterizing the spectra of the received signals are extracted from the output signals of each element of the antenna array, and for each selected frequency in the reception band, using the phase of the signals, a direct calculation of the spatial Fourier series is performed, discretely describing the angular power spectrum at the selected frequency. After restoration of the angular spectrum at all frequencies, the bearing of each source emitting signals at frequencies within the current reception band is determined. This method uses only phase information and has low efficiency in localizing the vast majority of types of complex signals.

Known more advanced method of computer-interferometric localization of complex signals [2], adopted as a prototype and includes:

- coherent radio signal reception by two spatially separated receiving channels;

- the formation of a signal describing the mutual correlation function (VKF), depending on the time shift of the signals received by a pair of receiving channels;

- allocation of the central part of the VKF;

- the conversion of the selected central part of the CCF to the complex mutual spectral density (VSP) of the received radio signal;

- comparison of the integrated VSP module with a threshold for detecting a radio signal and localizing the frequency region occupied by its spectrum, determining the width of the spectrum of the signal and its position on the frequency axis;

- measuring the angle of the phase slope of the integrated VSP in the localized frequency region to determine the direction of arrival of the received radio signal;

- indication of the results of detection, frequency localization and direction finding of the radio signal.

The prototype method is based on the formation and conversion of a one-dimensional VKF, depending on the time shift of the signals received by two spatially separated channels. This method effectively solves the problem of detecting and spatial-spatial localization of only one class of complex signals — time-continuous BPS type radio signals, provided that the central part of the CCF is in the region of zero delays, that is, with a small time shift between the received signals, which corresponds to a narrow angle sector the arrival of signals near the normal to the position line of the antennas of the two receiving channels.

However, when detecting and localizing in a wide sector of the angles of arrival of a large class of complex signals with a discrete time-frequency structure (pulse and packet BSS, WMS, LFM and their combinations), this method loses its effectiveness, since under conditions of a priori uncertainty regarding the shape and parameters of the signals It has a number of disadvantages that limit the probability of detection and localization of such signals.

The first disadvantage of the prototype is the low efficiency of spatial localization of signals at low input signal-to-noise ratios. This is due to the difficulty of reconstructing the full phase of the mutual spectral density of the localized signal with a wide variation of the time delay between the signals and the lack of delay compensation operations in the prototype to ensure the most favorable conditions for reconstructing the full phase.

The second disadvantage is due to the fact that the prototype lacks time selectivity. As a result, before measuring the direction of arrival of the signals, the problem of localizing the energy of the received signals only in frequency is solved. In this case, the noise power in the pauses between time-discontinuous emissions, for example, in the case of pulse and burst signals of an ALS or a WMS signal, is not filtered out and, with a large duty cycle of the radiation, it significantly reduces the signal-to-noise ratio and the quality of detection and measurement of bearings. When detecting and direction-finding chirp signals due to the influence of noise, there is also a significant decrease in efficiency due to the fact that the prototype method does not use a change in the frequency of the radio signal over time. In addition, the presence in the time-frequency region of the reception of signals with overlapping spectra leads to mutual interference.

Improving the efficiency of localization of complex signals when using the prototype method can be achieved in several well-known ways:

1) Increasing the base of the dual-antenna receiving array to improve the accuracy of signal localization along the angle of arrival.

However, the increase in the base of the antenna array is limited by the interval of spatial correlation of signals, which depends on the properties of the signal propagation medium and, in addition, leads to a decrease in the sector of working angles of the prototype method.

2) An increase in the number of elements of the antenna array.

However, this path is not always applicable and is often limited in practice by the conditions of placement of the antenna array, especially in mobile systems.

3) An increase in the duration of registration of an individual signal implementation or the use of several overlapping implementations to separate signals in time and to isolate them from noise due to accumulation in time.

This path also only partially increases the efficiency of localization of signals with a spread spectrum, since it loses its value when localizing short signals with a spread spectrum, that is, signals with both temporal and energy secrecy.

The technical result of the invention is to increase the efficiency of localization of several complex signals with an a priori unknown shape and time-frequency structure in a wide sector of angles.

The increase in efficiency was achieved thanks to additional information extracted from one implementation of the input data due to the transition from two-dimensional localization in frequency and direction of arrival to three-dimensional localization in frequency, time and direction of arrival of signals.

To achieve the specified technical result, a method for computer-interferometric localization of complex signals, including coherent reception of signals by two spatially separated receiving channels according to the invention,

synchronously convert the received signals into complex digital signals,

remember digital signals

from digital signals, pairs of channels for each expected direction of arrival of the received signals form a complex two-dimensional cross-correlation function (DCF), depending on the time and frequency shifts of the received signals,

allocate the central part of each complex DCF,

transform each highlighted central part of the complex DKVF into a complex function of mutual spectral density (FSPP),

use complex FVSP to detect and localize signals in frequency, time and direction of arrival,

Indicate the results of detection and localization of signals.

Particular cases of the method are possible:

1. The formation of an integrated DCFF for each expected direction of arrival of signals is carried out by time shifting the digital signal of one of the channels by a value corresponding to each expected direction of arrival of the received signals, using unshifted and shifted digital signals of a pair of channels in the formation of an integrated DCFF.

This ensures that the antenna array is guided to all possible directions of signal arrival and, as a result, improves the quality of the formation of the complex function of the mutual spectral density at subsequent stages of signal processing.

2. The formation of an integrated DCFF for each expected direction of arrival of signals is also carried out by summing the unshifted and shifted digital signals of the pair of channels, using the unshifted and total digital signals of the pair of channels in the formation of the integrated DCF.

This increases the sensitivity of localization of complex signals.

3. The formation of an integrated DCFF for each expected direction of arrival of signals is also carried out by using unshifted digital signals of a pair of channels in the formation of a complex DCFF, and the time shift of the formed integrated DCFF by an amount corresponding to each expected direction of arrival.

This reduces the amount of computation and, as a result, increases the speed of localization of complex signals.

4. Detection and localization of signals by frequency, time and direction of arrival is carried out by comparing the module of each integrated high-pass filter with a threshold and selecting closed time-frequency regions in which the threshold is exceeded, as the time-frequency areas of localization of individual signals for each direction of arrival, comparison signals overlapping in the time-frequency domain of different FVSP, selection in each overlapping group of a signal with maximum mutual energy and zero phase tilt angle of the FVSP in the time-frequency area of its localization, as well as fixing the direction of arrival of the selected signal.

This increases the efficiency of detection and localization of signals by frequency, time and direction of arrival.

The operation of the method is illustrated by drawings.

Figure 1. Block diagram of a computer interferometric device for localizing complex signals.

Figure 2. Two-dimensional cross-correlation function in the presence of two complex signals with matching angles of arrival in the time-frequency domain of reception:

a) the module of the complex two-dimensional cross-correlation function;

b) the module of the central two-dimensional part of the complex two-dimensional cross-correlation function.

Figure 3. The function of the mutual spectral density in the presence in the time-frequency domain of receiving two signals with matching angles of arrival:

a) the projection of the module of the complex function of the mutual spectral density on the time axis;

b) the projection of the module of the complex function of the mutual spectral density on the frequency axis;

c) the projection of the module of the complex function of the mutual spectral density on the time-frequency coordinate plane;

d) the modulus of the complex function of the mutual spectral density.

4 and 5. The function of the mutual spectral density in the presence of the time-frequency region of the reception of two signals with different angles of arrival.

6. The module (figa) and the argument (fig.6b) of the complex mutual spectral density of a complex signal, localized in frequency, time and direction of arrival.

The method of computer-interferometric localization of complex signals is as follows.

1. Coherently receive signals with two spatially separated receiving channels. As a result, signals x _n (t) are generated depending on the time t, where n = 1, 2 is the number of the receiving channel.

и

где z - номер временного отсчета сигнала.2. Synchronously convert the received signals x ₁ (t) and x ₂ (t) into complex digital signals

and

where z is the time reference number of the signal.

и

может быть выполнено различными способами. Например, аналогово-цифровым или полностью цифровым способами, основанными на преобразовании Гильберта [3, стр.65] или квадратурной дискретизации [3, стр.169]. Значение периода дискретизации Т_d должно быть много меньше минимального значения задержки между моментами прихода сигналов на две антенны, то есть

где d - расстояние между антеннами, Δ - шаг по углу, с - скорость света. Так при d=1000 м и Δ=0,1 градуса получаем

что соответствует частоте дискретизации 200 МГц. Отметим, что на современной элементной базе реализуемы частоты дискретизации, превышающие значение 1 ГГц.Converting received signals x ₁ (t) and x ₂ (t) into complex digital signals

and

can be performed in various ways. For example, analog-digital or fully digital methods based on the Hilbert transform [3, p. 65] or quadrature sampling [3, p. 169]. The value of the sampling period T _d should be much less than the minimum delay between the moments of arrival of the signals at two antennas, i.e.

where d is the distance between the antennas, Δ is the step along the angle, and s is the speed of light. So at d = 1000 m and Δ = 0.1 degrees we get

which corresponds to a sampling frequency of 200 MHz. Note that, on a modern elemental base, sampling frequencies exceeding 1 GHz are realizable.

и

на заданном временном интервале.3. Synchronously register complex digital signals

and

at a given time interval.

и

пары каналов для каждого ожидаемого направления m=1, ..., М прихода принятых сигналов формируют комплексную двухмерную взаимную корреляционную функцию (ДВКФ)

4. From complex digital signals

and

pairs of channels for each expected direction m = 1, ..., M of the arrival of the received signals form a complex two-dimensional cross-correlation function (DCF)

When forming a DCFF (in other words, the time-frequency mismatch function [4, p. 103]), the following actions are performed:

на величину τ^(m), соответствующую каждому ожидаемому направлению прихода m=1, ..., М принятых сигналов.- time shift the digital signal of one of the channels, for example, a signal

by the value τ ^(m) corresponding to each expected direction of arrival m = 1, ..., M of the received signals.

где d - расстояние между антеннами приемных каналов, с - скорость света.The values of the time shifts corresponding to each expected direction of arrival of the signals are calculated by the following formula:

where d is the distance between the antennas of the receiving channels, c is the speed of light.

и все последующие операции преобразования сигналов выполняют во временной или в частотной областях известными способами [5, стр.370].Signal shift

and all subsequent signal conversion operations are performed in the time or frequency domains by known methods [5, p. 370].

получают сдвинутый комплексный сигнал

Во втором случае из сигнала

получают комплексный временной спектр

где

- оператор дискретного преобразования Фурье (ДПФ) по времени, a k=0, ..., K-1 - номер частотного отсчета. Задержку сигнала

по времени на величину τ^(m) реализуют в частотной области умножением комплексного временного спектра сигнала

на вектор на комплексной плоскости ехр(-jω_kτ^(m)), где ω_k - частота, соответствующая k-му частотному отсчету. Задержанный комплексный сигнал получают по следующим формулам:

In the first of the signal

receive the shifted complex signal

In the second case, from the signal

get a comprehensive time spectrum

Where

is the discrete Fourier transform (DFT) operator in time, ak = 0, ..., K-1 is the number of the frequency reference. Signal delay

in time by the value of τ ^{(m) is} realized in the frequency domain by multiplying the complex time spectrum of the signal

per vector on the complex plane exp (-jω _k τ ^(m) ), where ω _k is the frequency corresponding to the k-th frequency sample. The delayed complex signal is obtained by the following formulas:

Thus, as a result of time shift operations, M shifted complex signals are obtained

Note that this operation can be considered as a component of the operation of pointing a 2-element antenna array into each of m = 1, ..., M angular directions, which is necessary for the subsequent separation and localization of received signals in space;

и сдвинутый

цифровые сигналы пары каналов при формировании комплексной ДВКФ

для каждого ожидаемого направления m=1, ..., М прихода принятых сигналов.- use unshifted

and shifted

digital signals of a pair of channels in the formation of a complex DCF

for each expected direction m = 1, ..., M of the arrival of the received signals.

выполняют во временной области

или в частотной области

где (...)^* означает комплексное сопряжение.The formation of integrated FEFF

perform in the time domain

or in the frequency domain

where (...) ^* means complex conjugation.

This ensures that the antenna array is guided in the selected direction of arrival of the signals and, as a result, improves the quality of the formation of the complex function of the mutual spectral density at subsequent stages of signal processing.

для каждого ожидаемого направления прихода m=1, ..., М сигналов также осуществляют следующим образом:To increase the sensitivity of localization of complex signals, the formation of an integrated DCF

for each expected direction of arrival, m = 1, ..., M signals are also carried out as follows:

и сдвинутый для m-го направления прихода

цифровые сигналы пары каналов для получения суммарного сигнала

- summarize the unshifted

and shifted for the m-th direction of arrival

digital signals of a pair of channels to obtain a total signal

и суммарный

цифровые сигналы пары каналов при формировании комплексной ДВКФ

для m-го направления прихода.- use unshifted

and total

digital signals of a pair of channels in the formation of a complex DCF

for the m-th direction of arrival.

или в частотной

областях.The formation is performed, as before, in the temporary

or in frequency

areas.

для каждого ожидаемого направления m=1, ..., М прихода сигналов также осуществляют следующим образом:To reduce the amount of computation and, as a result, increase the speed of localization of complex signals, the formation of an integrated DCF

for each expected direction m = 1, ..., M, the arrival of signals is also carried out as follows:

и

пары каналов при формировании комплексной ДВКФ

принятых сигналов.- use unshifted digital signals

and

pairs of channels in the formation of complex DCF

received signals.

или в частотной

областях;The formation is performed, as before, in the temporary

or in frequency

areas;

на величину, соответствующую каждому ожидаемому направлению m=1, ..., М прихода сигналов.- shift in time the formed complex DCF

by the value corresponding to each expected direction m = 1, ..., M of the arrival of signals.

The shift is performed as follows:

As a result of the performance of the described operations, M complex DVKF are obtained

каждой комплексной ДВКФ

5. Allocate the central two-dimensional part

each integrated FEFF

The parameters Δ and Θ are selected based on the need to suppress noise and side peaks of the mismatch function, which determine the level of mutual interference, as well as on the basis of the permissible level of distortion of the fronts of the pulses of the useful signal.

Применение двухмерного окна к комплексной ДВКФ

эквивалентно двухмерной фильтрации комплексной функции взаимной спектральной плотности, формируемой на следующем этапе.This operation can be considered as the operation of applying a two-dimensional window having a square or rectangular support region to a complex DCF

Application of a two-dimensional window to a complex DCF

equivalent to two-dimensional filtration of the complex function of the mutual spectral density formed in the next step.

комплексной ДВКФ и модуль

ее центральной двухмерной части, сформированные для углового направления, совпадающего с направлением прихода немодулированного радиоимпульса и радиоимпульса с ЛЧМ.On figa and figb as an example presents a module

integrated DCF and module

its central two-dimensional part, formed for the angular direction coinciding with the direction of arrival of the unmodulated radio pulse and the radio pulse with the LFM.

комплексной ДВКФ в комплексную функцию взаимной спектральной плотности (ФВСП)

6. Transform each highlighted central part

complex DKVF into a complex function of mutual spectral density (FVSP)

Модуль

комплексной ФВСП

может рассматриваться как спектрограмма или, другими словами, "изображение" частотно-временного распределения энергии сигналов в анализируемой частотно-временной области приема.As a result of the performance of the described operations get M complex FVSP

Module

integrated FSPP

can be considered as a spectrogram or, in other words, an “image” of the time-frequency distribution of the signal energy in the analyzed time-frequency reception region.

на временную (фиг.3а) и частотную (фиг.3б) оси, на частотно-временную координатную плоскость (фиг.3в) и собственно модуль

(фиг.3г) комплексной ФВСП, сформированной для углового направления, совпадающего с направлением прихода немодулированного радиоимпульса и радиоимпульса с ЛЧМ.Figure 3 presents the projection of the module

on the temporary (figa) and frequency (fig.3b) axis, on the time-frequency coordinate plane (fig.3c) and the module itself

(Fig. 3d) of an integrated FSPP formed for the angular direction coinciding with the direction of arrival of the unmodulated radio pulse and the radio pulse with LFM.

On figa - fig.4g presents the projection of the module and the actual module integrated FSPP, formed for the angular direction, coinciding with the direction of arrival of the unmodulated radio pulse.

On figa - fig.5g presents the projection of the module and the actual module integrated FSPP, formed for the angular direction, coinciding with the direction of arrival of the radio pulse with LFM.

As can be seen from figv and fig.3d, the proposed method provides a separation in frequency and time of several signals with matching angles of arrival. In addition, from figure 4 and figure 5, it follows that the proposed method provides separation by the angle of arrival of several signals simultaneously falling into the time-frequency region of the reception.

Thus, the described operations are fundamental for improving the detection and determination of the energy distribution in frequency, time and angular direction of a plurality of a priori unknown complex signals that simultaneously fall into the analyzed time-frequency receiving region.

используются на последующих этапах обработки для автоматизации операций обнаружения и локализации по частоте, времени и направлению прихода всей совокупности сигналов, одновременно попадающих в анализируемую область приема.Comprehensive FSPPs obtained for all expected directions of signal arrival

are used at subsequent processing stages to automate the detection and localization operations in frequency, time and direction of arrival of the entire set of signals simultaneously falling into the analyzed receiving area.

для обнаружения и локализации сигналов по частоте, времени и направлению прихода.7. Use complex FVSP

to detect and localize signals by frequency, time and direction of arrival.

In this case, the detection and localization of signals in frequency, time and direction of arrival is as follows:

каждой комплексной ФВСП с порогом С₀ для выбора замкнутых частотно-временных областей, в которых превышен порог С₀, в качестве частотно-временных областей локализации отдельных сигналов для каждого ожидаемого направления прихода. Порог С₀ выбирают, исходя из заданной вероятности ложной тревоги;- compare the module

each complex high-pass filter with threshold С ₀ for selecting closed time-frequency regions in which threshold С ₀ is exceeded, as time-frequency regions of localization of individual signals for each expected direction of arrival. The threshold C _{0 is} selected based on a given probability of false alarm;

- compare the signals overlapping in the time-frequency domain of different complex FVSP;

- in each overlapping group, a signal is selected with the maximum mutual energy and zero phase angle in the time-frequency region of its localization.

The signal energy is determined by summing the squares of the modules of the integrated high-pass filter in the time-frequency region of its localization. The degree of approach of the phase angle to zero is determined by known methods, for example, the least squares method.

An example of a module (amplitude spectrum) of a signal with maximum mutual energy in the form of a radio pulse with a chirp is shown in Fig.6a. The zero phase angle angle in the frequency domain occupied by the spectrum of the selected signal — the radio pulse with LFM, is shown in FIG. 6b;

- fix the direction of arrival of the selected signal.

а также связь номера m функции

с ожидаемыми угловыми направлениями прихода m=1, ..., М, которые, в свою очередь, являются направлениями наведения антенной решетки.In this case, an unambiguous relationship of the selected signal and the corresponding function is used.

as well as m function number relationship

with the expected angular directions of arrival m = 1, ..., M, which, in turn, are the directions of pointing the antenna array.

As follows from the described operations, at this stage, the direction of arrival and the time-frequency region of each received signal are simultaneously determined. In other words, at this stage, the spatial-frequency-time localization of the signals of all transmitters that simultaneously fall in the frequency-time domain of reception is realized;

8. Indicate the results of detection and localization of signals by frequency, time and direction of arrival.

From the above description of the proposed method, it follows that an increase in the efficiency of localization of several complex signals with an a priori unknown shape and time-frequency structure in a wide sector of angles was achieved by introducing the following operations:

- formation instead of a one-dimensional VKF of a two-dimensional VKF, which increases the information content of localization;

- shift of two-dimensional VKF to the region of zero delays, which increases the sensitivity and resolution of detection and localization of signals in space, frequency and time due to compensation of delays for each expected direction of reception;

- two-dimensional filtering in the correlation region instead of one-dimensional filtering, which also increases the sensitivity and resolution of detection and localization;

- the formation of the VSP function ("image" of the frequency-time distribution of signal energy) instead of VSP ("image" of the frequency distribution of signal energy), which also increases the information content and quality of localization;

- identification of time-frequency localization regions instead of frequency regions, which also increases the information content and quality of localization.

The effectiveness of the proposed method is confirmed by modeling in Mathcad 2001 for a wide range of distances between the antennas of the receiving channels, varying from units to thousands of wavelengths λ of the incident radiation and various values of the input signal-to-noise ratios.

The device (figure 1), which implements the proposed method, includes a series-connected antenna system 1, a two-channel frequency converter (RFH) 2, a two-channel quadrature sampling device 3, a computer 4, a display device 5.

Antenna system 1 contains two antennas combined in an array. To eliminate the ambiguity in space, antennas with a cardioid or sharper radiation pattern are used.

Two-channel RFR 2 and device 3 are made with a common local oscillator and with a bandwidth of each channel, providing simultaneous reception of several signals. A common local oscillator provides two-channel coherent reception of radio signals.

A device that implements a method of computer-interferometric localization of complex signals works as follows.

The radio signals of the transmitters are received by the antennas of the array 1. The time-dependent radio signal x _n (t) received by each antenna array 1 is coherently transferred to a lower frequency in the RFI 2.

и

синхронно преобразуются в двухканальном устройстве квадратурной дискретизации 3 в комплексные цифровые сигналы

и

Комплексные цифровые сигналы

и

синхронно регистрируется на заданном временном интервале в вычислителе 4.Signals generated in the RFR 2

and

synchronously converted in a two-channel quadrature sampling device 3 into complex digital signals

and

Integrated Digital Signals

and

synchronously recorded at a given time interval in the calculator 4.

In addition, in the calculator 4, the following actions are performed:

и

формируется комплексная ДВКФ

сигналов пары каналов для каждого ожидаемого направления m=1, ..., М прихода сигналов;- from complex digital signals of a pair of channels

and

integrated DVKF is being formed

signals of a pair of channels for each expected direction m = 1, ..., M of the arrival of signals;

каждой комплексной ДВКФ

- the central two-dimensional part stands out

each integrated FEFF

в комплексную ФВСП

- each highlighted central part is transformed

in integrated FVSP

каждой комплексной ФВСП

с порогом C₀ выбираются частотно-временные области локализации отдельных сигналов для каждого ожидаемого направления прихода;- comparing the module

each integrated FSPP

with a threshold C ₀ , the time-frequency regions of localization of individual signals for each expected direction of arrival are selected;

- the signals of different complex FVSP overlapping in the time-frequency domain are compared;

- a signal is selected in each overlapping group with a maximum mutual energy and a zero phase tilt angle in the time-frequency region of its localization and the direction of arrival of the selected signal is fixed.

The device 5 displays the results of detection and localization in frequency, time and direction of arrival of the entire set of signals simultaneously falling into the analyzed frequency-time region of reception.

Thus, by obtaining additional information extracted in a wide sector of angles from one implementation of the input data due to the transition from two-dimensional localization in frequency and direction of arrival to three-dimensional localization in frequency, time and direction of arrival of signals, which provides an increase in sensitivity and resolution, and as a result introduction of operations:

- the formation of a complex two-dimensional mutual correlation function of the received signals;

- two-dimensional filtering in the correlation region;

- the formation of complex functions of mutual spectral density for each expected direction of arrival of signals;

- identification of the time-frequency regions of signal localization for each expected direction of their arrival,

it is possible to solve the problem with the achievement of the technical result.

Information sources

1. US Patent No. 4,626,859, class. G01S 5/04, 1986

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Claims (5)

1. A method of computer-interferometric localization of complex signals, including coherent reception of signals by two spatially separated receiving channels, characterized in that the received signals are synchronously converted into complex digital signals, the digital signals are stored, a pair of channels for each expected direction of arrival of the received signals are generated from the digital signals a complex two-dimensional cross-correlation function (DCF), depending on the time and frequency shifts of the received signals, is isolated the central part of each complex DVKF, transform each distinguished central part of the complex DVKF into a complex function of mutual spectral density (FVSP), use complex FVSP to detect and localize signals in frequency, time and direction of arrival, indicate the results of detection and localization of signals. 2. The method according to claim 1, characterized in that the formation of a complex DKVF for each expected direction of arrival of the signals is carried out by time shifting the digital signal of one of the channels by the value corresponding to each expected direction of arrival of the received signals, using unshifted and shifted digital signals of the pair of channels at the formation of a comprehensive DCF. 3. The method according to claim 2, characterized in that the formation of a complex DCIF for each expected direction of arrival of the signals is also carried out by summing the unshifted and shifted digital signals of the pair of channels, using the unshifted and total digital signals of the pair of channels in the formation of the complex DVKF. 4. The method according to claim 1, characterized in that the formation of a complex DCF for each expected direction of arrival of the signals is also carried out by using unshifted digital signals of a pair of channels in the formation of a complex DCF, the time shift of the integrated DCF by an amount corresponding to each expected direction of arrival. 5. The method according to claim 1, characterized in that the detection and localization of signals by frequency, time and direction of arrival is carried out by comparing the module of each complex high-pass filter with a threshold for selecting closed time-frequency regions in which the threshold is exceeded, as time-frequency areas of localization of individual signals for each direction of arrival, comparing signals overlapping in the time-frequency domain of signals of different complex high-pass signals, selecting in each overlapping group a signal with maximum mutual energy and zeros the right angle of the phase inclination of the FSPP in the time-frequency region of its localization, as well as fixing the arrival direction of the selected signal.

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