RU2341811C1 - Method of finding direction of radio signals and direction finder to this end - Google Patents

Abstract

FIELD: physics.

SUBSTANCE: essence of the proposed method lies in converting received radio signals to digital form, measuring, in each frequency sub-range at coinciding time intervals, complex spectra of signal pairs for each pair of antenna elements of an antenna array, and determination of the convolution of complex conjugate spectra. The phase difference of radio signals is obtained for each pair of antenna elements and each frequency sub-range by Fourier transformation. Standard phase differences of signals are formed and stored for all possible directions of incoming radio signals. The variance function of residual errors of phase differences is calculated from all angular parameters. The probable direction of the incoming radio signal is determined from the least sum of squares of residual errors, simultaneously with calculation of the mutual power of signals for all pairs of antenna elements and all frequency sub-ranges. The total and average power of signals is determined, as well as frequency ranges, in which values of average signal power exceeds the given threshold. Bearing values corresponding to these sub-ranges are stored. The spectrum width of signals is determined from the number of adjacent bearings of the same type. The average frequency value of the signal is determined for all detected radiation. The measured frequency band of assessed signals is separated for subsequent determination of the most probable direction of incoming radio signals. In the direction finder, which employs this method, there are also three memory devices, first, three pulse counters, second adder, divider, two comparator units, second adjustment bus, "AND" elements unit, unit for determining average signal frequency and a digital band pass filter, all connected in a well defined way between themselves and the rest of the components of the proposed direction finder.

EFFECT: more accurate measurement.

2 cl, 11 dwg

Description

The inventive objects are united by a single inventive concept, relate to radio engineering and can be used in navigation, direction finding, location tools, as well as in radio monitoring tools to determine the bearing and elevation to the source of an a priori unknown signal.

A known method of direction finding of radio signals, including receiving radio signals of a five-element equidistant ring antenna array made of omnidirectional antennas located in the direction-finding plane, converting radio signals by a two-channel receiver, measuring phase differences between the converted signals received by individual pairs of omnidirectional antennas, comparing all measured phase differences between each other, which judge the value of the bearing (application UK No. 2140238, G01S 3/48, publ. 1984).

The disadvantage of this method is the insufficient accuracy of direction finding at low signal-to-noise ratios and the inability to obtain information about the angle of inclination of the wave front of the radio signal source.

A known method of direction finding a signal source (see US Pat. No. 2192651, G01S 3/14, G01S 3/00, publ. 05.10.2000), comprising receiving a direction-finding signal by elements of two linear equidistant antenna arrays arranged mutually perpendicularly, the calculation of spatial Fourier spectrum of the direction-finding signal received by the elements of the first linear equidistant antenna array and the complex conjugate spatial spectrum of the direction-finding signal received by the elements of the second linear equidistant antenna array, scale transformation of both calculated spatial spectra of the direction finding signal according to the logarithmic law, correlation analysis and measuring the relative shift of the converted spatial spectra of the direction finding signal and estimating the angular coordinates.

The disadvantage of this method is the dependence of the accuracy of the measurement of the bearing on the mutual orientation of the radiation source and the direction-finding system of the direction finder, the inability to obtain information about the angle of inclination of the wave front of the radio signal β.

A known method of direction finding according to US Pat. No. 2144200, IPC7 G01S 3/14. Method for direction finding of radio signals and multi-channel direction finder. Publ. October 1, 2000, it includes the reception of radio signals by an antenna array consisting of N antenna elements made identical in an amount of at least three and located in the direction-finding plane, measuring in each frequency subband the complex amplitudes of pairs of signals characterizing the phases of each radio signal received in the corresponding frequency subband by one of the antenna elements of the pair selected as a signal relative to the phase of the radio signal received in the same frequency subband by another of the antenna elements of the pair s, selected as a reference for all pairs of antenna elements used, the formation of two-dimensional angular spectra of each received in the corresponding frequency subband radio signal from the measured complex amplitudes of the signal pairs for different pairs of antenna elements of the antenna array according to the relative position of these antenna elements in the direction-finding plane, by which they judge azimuths and elevation angles of received radio signals.

The analogue method allows to increase the direction finding accuracy when scanning in a wide frequency range and obtain information about the angle of inclination of the wave front of the radio signal source. However, the method also has a disadvantage - low direction finding accuracy in a complex signal-noise environment. The method does not fully use information about the field of the direction-finding radio signal embedded in the geometry of the antenna system. In addition, in this method, the direction finding accuracy is reduced due to the non-synchronous connection (via the switch) of the antenna elements of the pair to the inputs of the two-channel receiver.

The closest in technical essence to the proposed method is the direction finding method according to US Pat. RU No. 2263327, IPC7 G01S 3/14 Method for direction finding of radio signals and direction finder for its implementation. Publ. 10/27/2005, bull. No. 30. It includes the reception of radio signals in the corresponding frequency subband Δf _v , Δf _v ∈ΔF, v = 1,2, ... V, V = ΔF / Δf, antenna array,

consisting of N identical omnidirectional antenna elements, where N> 2, located in the direction-finding plane and locally adapted to local conditions, sequential synchronous conversion of high-frequency signals of each pair of antenna elements of the antenna array into electrical signals of intermediate frequency, their discretization and quantization, formation of them four sequences of samples by dividing into quadrature components, storing in each sequence a given number of samples vadture components of signals, correction of stored samples of sequences of quadrature components by successively multiplying each of them by the corresponding sample of a given time window, generating from the corrected sequences of quadrature components of the samples of signals two complex sequences of samples of signals, the elements of which are determined by pairwise combining of the corresponding samples of the corrected sequences of quadrature components of the signals en ennyh elements, converting both complex sequences of signal samples through a Discrete Fourier Transform, pairwise multiplication sampling signal converted sequence of one antenna element to the corresponding complex conjugate samples of the transformed sequence signal at the same frequency as the other antenna element A _{l, h,} where l, h = 1 , 2, ..., N, l ≠ h, calculation for the current pair of antenna elements of the phase difference of the signals for each frequency subband according to the formula Δφ _{l, h, ISM} (f _v ) = arctg (U _c (f _v ) / U _s (f _v )) , storing the obtained phase differences of the radio signals, generating and storing the reference set of phase differences of the signals based on the spatial arrangement of the antenna elements of the antenna array, the used frequency range and the given measurement accuracy, subtracting the corresponding values of the measured phase differences from the standard phase differences of the signals, squaring the obtained residual values and their summation over all pairs of antenna elements and all frequency subbands, storing the received amounts located one correspondence with the arrival directions of radio signals, to determine the most likely arrival direction of the radio signal in the horizontal and elevation planes for the lowest sum of squared residuals.

The prototype method allows us to solve the task assigned to it - to improve the quality of direction finding, namely to increase its accuracy. However, the prototype method also has a disadvantage associated with low accuracy of direction finding in a complex signal-noise environment, when the spectra of signals from various sources border in the frequency domain or partially overlap. On the other hand, non-optimal reception of the evaluated signals (over the frequency band) leads to a deterioration in the signal / (noise + noise) ratio, which ultimately affects the real sensitivity of the direction finder and its accuracy characteristics.

The closest in technical essence to the proposed device is the direction finder according to US Pat. RU No. 2263327, IPC7 G01S 3/14. Method for direction finding of radio signals and direction finder for its implementation. Publ. 10/27/2005, bull. No. 30. The prototype device contains an antenna array made of N> 2 identical omnidirectional antenna elements located in the direction-finding plane and an accommodation option agreed with local conditions, an antenna switch, N inputs of which are connected to the corresponding N outputs of the antenna array, and the signal and reference outputs of the switch are connected respectively, to the signal and reference inputs of a two-channel receiver made according to the scheme with common local oscillators, an analog-to-digital converter made by two-channel respectively, with the signal and reference channels, and the signal and reference outputs of the intermediate frequency of the two-channel receiver are connected respectively to the signal and reference inputs of an analog-to-digital converter, the Fourier transform unit made two-channel, respectively, with the signal and reference channels, the signal and reference inputs of which are connected respectively with the signal and reference inputs of an analog-to-digital converter, the first and second storage devices, a subtraction unit, a reference generating unit values of phase differences, the primary spatial information parameters calculation unit, the first information input of which is connected to the signal output of the Fourier transform unit, and the second input - with the reference output of the Fourier transform unit, the first group of information outputs of the primary spatial information parameters calculation unit the inputs of the second storage device, the group of information outputs of which are connected to the group of inputs of the subtracted subtraction block, group the reduced path of which is connected to the information outputs of the first storage device, the information inputs of which are connected to the information outputs of the unit for generating the phase difference reference values, the group of information inputs of which is the input mounting bus of the direction finder, the multiplier connected in series, the first adder, the third memory, the azimuth determination unit and elevation, and the first and second groups of information inputs of the multiplier are combined and connected to a group of formation outputs of a subtraction unit, a clock generator, the output of which is connected to the control input of the antenna switch, synchronization inputs of an analog-to-digital converter, Fourier transform unit, first, second and third storage devices, subtraction unit, multiplier, first adder, azimuth and elevation determination unit , a unit for generating reference values of phase differences and a unit for calculating primary spatial information parameters.

The aim of the claimed technical solutions is to develop a method of direction finding of radio signals and direction finder for its implementation, providing improved direction finding accuracy in a complex signal-noise environment, when the spectra of signals from various sources border on the frequency domain or partially overlap.

The goal is achieved by the fact that in the known method of radio direction finding, comprising a receiving radio signals in the respective sub-band frequencies _{Δf v, Δf v ∈ΔF, v} = 1,2, ... V, V = ΔF / Δf, an antenna array consisting of N identical omnidirectional antenna elements, where N> 2, located in the direction-finding plane and the placement variant agreed with local conditions, sequential synchronous conversion of high-frequency signals of each pair of antenna elements of the antenna array into electrical signals of intermediate frequency, discrete their synthesis and quantization, the formation of four sequences of samples from them by dividing into quadrature components, storing in each sequence a given number of B samples of the quadrature components of the signals, the correction of the stored samples of sequences of quadrature components by sequentially multiplying each of them by the corresponding sample of the specified time window, the formation of corrected sequences of quadrature components of the samples of the signals of two complex been consistent signal samples whose elements are determined by pairwise combining respective samples of the corrected sequence of quadrature component signals of the antenna elements, the transformation of both the complex sequences of signal samples through a Discrete Fourier Transform, pairwise multiplication of signal samples of the transformed sequence of one antenna element A _l to corresponding complex conjugate of the signal samples are converted sequences on t the same frequency of the other antenna element А _h , where l, h = 1,2, ..., N, l ≠ h, calculation for the current pair of antenna elements of the phase difference of the signals for each frequency subband according to the formula Δφ _{l, h, ISM} ( f _v ) = arctan (U _c (f _v ) / U _s (f _v )), storing the obtained phase differences of the radio signals, generating and storing a reference set of phase differences of the signals based on the spatial arrangement of the antenna elements of the antenna array, the frequency range used and the given accuracy measurements, subtraction from the reference phase differences of the signals of the corresponding values measured phase differences, squaring the obtained values of the residuals and summing them over all pairs of antenna elements and all frequency subbands, storing the received sums that are in unambiguous correspondence with the directions of arrival of the radio signals, determining the most probable direction of arrival of the radio signal in horizontal and elevation planes by the smallest amount squared residuals.

Запоминают полученные значения взаимной мощности P_l,h(f_v), определяют суммарную мощность сигналов P(f_v) путем суммирования взаимных мощностей по всем парам антенных элементов для каждого частотного поддиапазона Δf_v. Запоминают значения суммарной мощности сигнала. Вычисляют среднее значение мощности сигнала

в каждом частотном поддиапазоне по формуле

где η - количество используемых в обработке антенных пар, определяют частотные поддиапазоны

, в которых значение средней мощности сигнала превышает заданный порог Р_пор. Запоминают значения пеленгов, соответствующих поддиапазонам

. Определяют ширину спектров сигналов

по количеству m прилегающих пеленгов Θ_j одного наименования по формуле Δf_ci=Δf×m. Определяют среднее значение частоты сигнала

для всех обнаруженных излучений по формуле

где

- верхняя частота спектра i-го сигнала. Совместно запоминают средние значения частот сигналов

_ci и соответствующие им полосы частот Δf_ci. Последовательно во всем диапазоне ΔF выделяют полосы частот Δf_ci, подавляя мешающие сигналы и уточняют наиболее вероятное направление прихода радиосигналов в горизонтальной и вертикальной плоскостях.For each pair of antenna elements and each subband, the values of the mutual power of the signals P _{l, h} (f _v ) are calculated by the formula

Remember the obtained values of the mutual power P _{l, h} (f _v ), determine the total power of the signals P (f _v ) by summing the mutual powers over all pairs of antenna elements for each frequency subband Δf _v . The values of the total signal power are stored. The average signal power is calculated

in each frequency subband according to the formula

where η is the number of antenna pairs used in processing, frequency subbands are determined

In which the average signal strength value exceeds a predetermined threshold R _then. Bearing values of bearings corresponding to subranges

. Determine the width of the spectra of the signals

on the number m of adjacent bearings of one Θ _j here the formula Δf _ci = Δf × m. Determine the average signal frequency

for all detected radiation according to the formula

Where

- the upper frequency of the spectrum of the i-th signal. Together remember average values of frequencies of signals

_ci and their corresponding frequency bands Δf _ci . Consistently in the entire range ΔF, frequency bands Δf _ci are distinguished, suppressing interfering signals and specify the most probable direction of arrival of radio signals in the horizontal and vertical planes.

Thanks to the new set of essential features in the claimed method, a more complete account of information about the frequency spectrum of the direction-finding signal is achieved, which allowed the adaptation of the receiving paths to be implemented. The latter caused a positive effect in the form of increasing the accuracy of direction finding of the IRI in the conditions of a complex signal-noise environment.

In the inventive direction finder, the goal is achieved by the fact that in the known device consisting of an antenna array made of N> 2 identical omnidirectional antenna elements located in the direction finding plane and adapted to local conditions, an antenna switch, N inputs of which are connected to the corresponding N the outputs of the antenna array, and the signal and reference outputs of the switch are connected respectively to the signal and reference inputs of the two-channel receiver, made according to the scheme with common the terody, an analog-to-digital converter, made two-channel, respectively, with the signal and reference channels, and the signal and reference outputs of the intermediate frequency of the two-channel receiver are connected respectively to the signal and reference inputs of the analog-to-digital converter, the Fourier transform unit, made two-channel, respectively, with the signal and reference channels, the first and second storage devices, a subtraction unit, a unit for generating reference values of phase differences, a primary calculation unit spatial information parameters, the first information input of which is connected to the signal output of the Fourier transform unit, and the second input is connected to the reference output of the Fourier transform unit, the first group of information outputs of the primary spatial information parameters calculation unit is connected to the group of information inputs of the second storage device, group information outputs of which is connected to the group of inputs of the subtracted subtraction block, the group of inputs of which is to be reduced is connected to the information the output outputs of the first storage device, the information inputs of which are connected to the information outputs of the unit for generating the reference values of the phase differences, the group of information inputs of which is the first mounting bus of the direction finder, series-connected multiplier, the first adder, the third storage device, the azimuth and elevation determining unit, the first and the second group of information inputs of the multiplier are combined and connected to the group of information outputs of the subtraction block, the gene clock generator, the output of which is connected to the control input of the antenna switch, synchronization inputs of an analog-to-digital converter, Fourier transform unit, first, second and third storage devices, a subtraction unit, a multiplier, a first adder, an azimuth and elevation determining unit, a reference value generating unit phase differences and the unit for calculating the primary spatial information parameters, additionally introduced the fourth, fifth and sixth storage devices, the block of elements "And", p the first, second and third pulse counters, the second adder, the divider, the first and second comparison units, the unit for determining the average frequency of the signal and a digital bandpass filter, made two-channel, and the first and second signal inputs of the digital bandpass filter are connected to the outputs of the signal and reference channels of the analog digital converter, respectively, and the first and second signal outputs are connected respectively to the signal and reference inputs of the Fourier transform unit, the first counter is connected in series, the fifth a memory device, a second adder, a divider, a sixth memory device and a first comparison unit, the counting input of the first pulse counter being combined with the synchronization inputs of the fifth memory device, the second adder, a digital band-pass filter and the output of the clock generator, and the zeroing output of the first pulse counter is connected to the inputs control of the second adder and divider, synchronization inputs of the sixth storage device and the first comparison unit, and the counting input of the second counter of impulses xs, the group of information outputs of which is connected to the first group of information inputs of the unit for determining the average frequency of the signal and the corresponding second inputs of the block of elements "And", the first inputs of which are combined and connected to the output of the first block of comparison, and the outputs of the block of elements "And" are connected to the group address inputs of the fourth storage device, the first and second groups of information inputs of which are connected to the first and second group of information outputs of the unit for determining the azimuth and elevation, and the first and the second group of information outputs of the fourth storage device are respectively the first and second output buses of the direction finder, the second installation bus of which is connected to the second group of information inputs of the first comparison unit, the group of information inputs of the second comparison unit is combined with the second output bus of the direction finder, the first output of the second comparison unit is connected with the counting input of the third pulse counter, and the second output with the zeroing input of the third pulse counter, information group Exit of which is connected with the second group of information inputs unit determining the average frequency of the signal, the group of information outputs of which is connected to the groups of the control inputs of the digital bandpass filter and a two-channel receiver.

The listed new set of essential features due to the fact that new elements and communications are introduced allows to achieve the purpose of the invention: to provide higher accuracy of direction finding of radio signals in a complex signal-noise environment.

The analysis of the prior art allows us to establish that analogues that are characterized by a combination of features that are identical to all the features of the claimed method of direction finding of radio signals and direction finder for its implementation are absent and, therefore, the claimed object has the property of novelty.

The study of known solutions in this and related fields of technology in order to identify signs that match the distinctive features of the prototype of the features of the claimed method and device showed that they do not follow explicitly from the prior art, from which the influence of transformations provided for by the essential features of the claimed invention is not known, to achieve the specified result, which allows us to consider the claimed object that meets the condition of patentability "inventive step".

The claimed method and device are illustrated by drawings, in which:

figure 1 presents the structural diagram of the direction finder;

figure 2 shows the order of dividing a given frequency band ΔF into subbands Δf;

3 illustrates a procedure for forming an array of reference values Δφ _{l, h, ET} (f _v);

figure 4 shows the order of formation of the array of measured values Δφ _{l, h, ISM} (f _v );

figure 5 illustrates the formation of an array of measured values of P _{l, h, ISM} (f _v );

поддиапазона v для ΔΘ₁, и различных углов места Δβ_c;figure 6 shows the procedure for calculating the sum

the subband v for ΔΘ ₁ , and various elevation angles Δβ _c ;

размерности С для каждого направления ΔΘ_k;figure 7 shows the order of formation of the vector columns

dimension C for each direction ΔΘ _k ;

on Fig shows the amplitude spectrum of the signals and the corresponding frequency-bearing panorama;

figure 9 presents used for processing pairs of AE:

a) 8 - elemental antenna array and a fully accessible antenna switch;

b) 16 - element antenna array when using a fully accessible antenna switch;

figure 10 shows the algorithm for calculating the reference phase difference;

figure 11 shows the algorithm for calculating the width of the spectrum of direction-finding signals and their center frequency.

The implementation of the proposed method is illustrated as follows. At the preparatory stage, the following operations are performed.

The entire specified frequency range ΔF is divided into subbands, the sizes of which Δf are determined by the minimum transmission bandwidth of the receiving paths of the direction finder. Subbands, the number of which V = ΔF / Δf are numbered v = 1,2, ..., V (see figure 2). The average frequencies of all subbands are calculated by the formula f _v = Δf (2v-1) / 2.

The next step is calculated reference values of primary-space information parameters (IPPU) for medium frequencies of all sub-bands f _v. As the primary spatial information parameters, the phase differences of the signals Δφ _{l, h} (f _v ) and the values of the mutual power of the signals P _{l, h} (f _v ) are used for all possible pair combinations of antenna elements within the antenna array.

The choice of Δφ _{l, h} (f _v ) and P _{l, h} (f _v ) as the PPIP is based on the following. One of the most promising directions for the implementation of measuring spatial parameters of signals from radio emission sources (IRI) is the use of interferometric direction finders (see Loginov N.A. Actual issues of radio monitoring in the Russian Federation - M .: Radio and Communication, 2000, pp. 138-139). Interferometers exist of two types: phase and correlation (see also p. 138) and are based on the use of Δφ _{l, h} (f _v ) and P _{l, h} (f _v ), respectively. The accuracy characteristics of direction finders realized with their help are close to each other, and some differences are manifested in different conditions of their application. In the proposed method of direction finding and direction finder, both PPIP are used to obtain maximum information about the signal field: Δφ _{l, h} (f _v ) and P _{l, h} (f _v ). The procedure for calculating the reference values Δφ _{l, h} (f _v ) is as follows.

The topology of the antenna system (AS) of the direction finder is introduced. Data on the topology of the speakers include the values of the mutual distances between the antenna elements of the array and its orientation relative to the north direction. As the latter, it is possible to use a vector passing from the second AE in the direction of the first AE (with the annular structure of the antenna array).

In the process of calculating the reference primary spatial information parameters, the placement of the reference source alternately around the direction finder antenna array with discreteness ΔΘ _k and Δβ _c at a distance of several wavelengths is simulated. It is assumed that the front of the incoming wave is flat. For each of the angular parameters ΔΘ _k , k = 1,2, ..., K and Δβ _c , c = 1,2, ..., C, the values of the phase differences Δφ _{l, h, ET} (f _v ) are calculated for all possible combinations of pairs of antenna elements of the array and all frequency subbands V:

Where

the distance between the planar wave front in the l-prefecture and h-prefecture antenna elements have come to the grating under angles ΔΘ _k in azimuthal and Δβ _c in vertical _{planes, l ≠ h, x l,} y l, z l and x _h, y _h , z _{h are the} coordinates of the lth and hth antenna elements of the array. C 'is the speed of light. In the case of using an antenna array with flat (horizontal) AE placement (z _l = z _h ), the last expression takes the form:

Received as a result of measurements, the reference values of the PPIP Δφ _{l, h, ET} (f _v ) are made out in the form of a reference data array, a variant of the presentation of information in which is shown in Fig.3.

When a signal is detected in a given frequency band of the LR, two arrays of measured PPIP Δφ _{l, h, ISM} (f _v ) and P _{l, h, ISM} (f _v ) are formed (see Fig. 4 and Fig. 5), the information presentation structure in which is similar to that discussed above in figure 3. To do this, in the direction finder, all measured values Δφ _{l, h, ISM} (f _v ) and P _{l, h, ISM} (f _v ) for all combinations of pairs of antenna elements A _{l, h of} all V frequency subbands are drawn into the corresponding two arrays of PPIP.

The subsequent operations in the proposed method of direction finding is carried out in parallel in two directions. In the first of them, similarly to the prototype method, sequentially for all directions ΔΘ _k , k = 1,2, ..., K; KΔΘ _k = 2π, and all elevation angles Δβ _c , s = 1,2, ..., C; SΔβ _c = π / 2 calculating a difference between the reference Δφ _{l, h, ET} (f _v) and measured Δφ _{l, h, MOD} (f _v) IPPU which are squared and summed in accordance with the expression

в поддиапазоне Δf_v для ΔΘ₁ различных значений угла места Δβ_c. Для каждого направления ΔΘ_k, k=1,2,...,K, формируется вектор-столбец

размерности С из соответствующих значений

(см. фиг.7).6 illustrates the order of calculation of the sums

in the subband Δf _v for ΔΘ ₁ different elevation angles Δβ _c . For each direction ΔΘ _k , k = 1,2, ..., K, a column vector is formed

dimension C from the corresponding values

(see Fig.7).

квадратов невязок среди

для всех V частотных поддиапазонов.Determining the most probable direction of arrival of the radio signal in the horizontal and elevation planes is carried out by searching for the smallest amount

squares of residuals among

for all V frequency subbands.

In parallel with the above operations, the total signal power P (f _v ) is determined by summing the mutual powers P _{l, h} (f _v ) over all pairs of antenna elements for each frequency subband:

для каждого частотного поддиапазона:The next operation performed in the proposed method is the calculation of the average signal power

for each frequency subband:

v=1,2,...,V, в дальнейшем используются для выполнения операции сравнения с заданным порогом Р_ПОР. Порядок выбора значения Р_ПОР известен (см. Г.И.Тузов, В.А.Сивов, В.И.Прытков и др. Помехозащищенность радиосистем со сложными сигналами. Под ред. Г.И.Тузова. - М.: Радио и связь, 1985, стр.144-146).where η is the number of antenna pairs used in processing. Values obtained

v = 1,2, ..., V, are further used to perform the comparison operation with a given threshold P _POR . Procedure for selecting the values of P _POR known (see G.I.Tuzov, V.A.Sivov, V.I.Prytkov et al Immunity radio systems with complex signals, Ed G.I.Tuzova -..... M .: Radio and Communication, 1985, pp. 144-146).

и Р_ПОР определяют частотные поддиапазоны

, в которых с заданной вероятностью обнаружены оцениваемые сигналы. Значения

запоминаются совместно с соответствующими им значениями пеленга Θ_j. Следует отметить, что в предлагаемом способе селекция сигналов различных ИРИ осуществляется только по значению Θ_j как наиболее информативному параметру. Угол места β_i в большинстве практических случаев близок к нулю и поэтому малоинформативен. Кроме того, точность измерения угла места β_i, как правило, ниже точности измерения пеленга Θ_j в силу реализационных особенностей используемых антенных решеток.As a result of the performance comparison operation

_ERP is determined and P frequency subbands

in which estimated signals are detected with a given probability. Values

are stored together with the corresponding values of bearing Θ _j. It should be noted that in the proposed method, the selection of signals of various IRI is carried out only by the value Θ _j as the most informative parameter. The elevation angle β _i in most practical cases is close to zero and therefore uninformative. In addition, the accuracy of measuring the elevation angle β _i , as a rule, is lower than the accuracy of measuring the bearing Θ _j due to the implementation features of the used antenna arrays.

и соответствующих им пеленгах принимается решение о ширине спектров обнаруженных сигналов Δf_ci.Based on subband information received

and their corresponding bearings, a decision is made on the spectral width of the detected signals Δf _ci .

As a criterion for this decision in the proposed method uses the approximate equality of the parameter Θ _j property for all components of the spectrum of a signal Iran. In this case, the spread of bearing values for adjacent subranges is allowed to be within small limits (for example, ΔΘ = 2 ° -3 °) due to measurement errors due to a number of well-known reasons (see Fig. 8).

After finding the values Δf _ci = Δf × m determine the average frequencies of the detected signals IRI

- верхняя частота i-го сигнала.Where

- the upper frequency of the i-th signal.

последовательно во всем диапазоне ΔF выделяют полосы частот Δf_ci, подавляя соседние мешающие сигналы и уточняют наиболее вероятное направление прихода радиосигналов в горизонтальной и вертикальной плоскостях.At this preparatory stage of frequency adaptation ends. Based on the information received on Δf _ci and

consistently throughout the range ΔF allocate bandwidth Δf _ci suppressing neighboring interfering signals and clarify the most likely direction of arrival of radio signals in the horizontal and vertical planes.

Thus, in the proposed method PPIP P _{l, h} (f _v ) are used to perform the operation of frequency adaptation of the meter in order to improve the accuracy of the obtained estimates of the parameters Θ and β.

The direction finder (Fig. 1) contains an antenna array 5 made of N> 2 identical omnidirectional antenna elements located in the direction-finding plane and a locally adapted arrangement, the antenna switch 6, the N inputs of which are connected to the corresponding N outputs of the antenna array, and the signal and the reference outputs of the switch are connected respectively to the signal and reference inputs of the two-channel receiver 7, made according to the scheme with common local oscillators, the analog-to-digital converter 8, made two-channel respectively, with the signal and reference channels, the signal and reference outputs of the intermediate frequency of the two-channel receiver connected respectively to the signal and reference inputs of the analog-to-digital converter, the Fourier transform unit 10, made two-channel, respectively, with the signal and reference channels, the unit for calculating the primary spatial information parameters 11 , the first information input of which is connected to the signal output of the Fourier transform unit 10, and the second input is connected to the reference output of the pre Fourier transform 10, the first group of information outputs of the primary spatial information parameters calculation unit 11 is connected to the group of information inputs of the second storage device 12, the group of information outputs of which is connected to the group of inputs of the subtracted subtraction unit 13, the group of inputs of which is reduced is connected to the information outputs of the first memory device 4, the information inputs of which are connected to the information outputs of the unit for generating the reference values of the phase differences 3, the group of information inputs of which is the first mounting bus 1 of the direction finder, the multiplier 14 connected in series, the first adder 15, the third storage device 16, the azimuth and elevation angle determination unit 17, the first and second group of information inputs of the multiplier 14 are combined and connected to the group of information outputs of the block subtraction 13, the clock generator 2, the output of which is connected to the control input of the antenna switch 6, synchronization inputs of the analog-to-digital converter 8, the conversion unit Fourier 10, first 4, second 12 and third 16 storage devices, a subtraction unit 13, a multiplier 14, a first adder 15, a block for determining the azimuth and elevation angle 17, a unit for generating reference values of phase differences 3 and a unit for calculating primary spatial information parameters 11 .

To improve the accuracy of direction finding, the fourth 18, fifth 22 and sixth 25 memory devices, the block of elements “I” 27, the first 21, the second 28 and the third 31 pulse counters, the second adder 23, the divider 24, the first 26 and the second 32 comparison blocks, block were introduced determining the average frequency of the signal 30 and the digital band-pass filter 9, made two-channel, and the first and second signal inputs of the digital band-pass filter 9 are connected to the outputs of the signal and reference channels of the analog-to-digital converter 8, respectively, and the first and second signal the outputs are connected respectively to the signal and reference inputs of the Fourier transform unit 10, the first counter 21, the fifth memory 22, the second adder 23, the divider 24, the sixth memory 25 and the first comparison unit 26 are connected in series, and the counting input of the first pulse counter 21 is combined with the synchronization inputs of the fifth memory device 22, the second adder 23, the digital band-pass filter 9 and the output of the clock generator 2, and the zeroing output of the first pulse counter 21 is connected to the control inputs the occurrence of the second adder 23 and the divider 24, the synchronization inputs of the sixth memory device 25 and the first comparison unit 26, and the counting input of the second pulse counter 28, the group of information outputs of which are connected to the first group of information inputs of the unit for determining the average frequency of the signal 30 and with the corresponding second inputs of the block elements "And" 27, the first inputs of which are combined and connected to the output of the first comparison unit 26, and the outputs of the block of elements "And" 27 are connected to the group of address inputs of the fourth storage device 18, the first and second groups of information inputs of which are connected to the first and second group of information outputs of the unit for determining the azimuth and elevation angle 17, and the first and second group of information outputs of the fourth storage device 18 are respectively the first 19 and second 20 output direction finding buses, the second installation the bus 29 of which is connected to the second group of information inputs of the first comparison unit 26, the group of information inputs of the second comparison unit 32 is combined with the second output bus 20 pele gator, the first output of the second comparison unit 32 is connected to the counting input of the third pulse counter 31, and the second output is to the zeroing input of the third pulse counter 31, the group of information outputs of which is connected to the second group of information inputs of the unit for determining the average frequency of the signal 30, the group of information outputs of which connected to groups of control inputs of a digital band-pass filter 9 and a two-channel receiver 7.

. Ширина поддиапазонов Δf_v определяются минимальной шириной пропускания приемных трактов пеленгатора. Для этого предварительно осуществляется описание пространственных характеристик антенной решетки 5. С этой целью измеряются взаимные расстояния между антенными элементами А_l,h решетки 5 (см. фиг.9) при их размещении на горизонтальной плоскости. В общем случае (Z_l,h≠0) используются расстояния между проекциями пространственного размещения АЭ на горизонтальную плоскость, проходящую через первый антенный элемент. В этом случае для каждого АЭ дополнительно измеряются значения {Z_l,h} как {Z_l,h}={Z_l} - {Z_h}. Результаты измерений по шине 1 (см. фиг.1) поступают на вход блока формирования эталонных значений ППИП 3. Здесь по известному алгоритму (см. пат.RU №2283505, МПК 7 G01S 13/46, опубл. 10.09.2006 г., бюл. №25; пат.RU №2263328, опубл. 24.05.2004 г., бюл. №30) вычисляются значения Δφ_l,h,ЭТ(f_v), которые в дальнейшем хранятся в первом запоминающем устройстве 4 (см. фиг.3). Вводится склонение Θ_скл антенной решетки 5 относительно направления на север, например, как угол между векторами, проходящими через первый и второй АЭ и центр АР и направлением на север.The direction finder (figure 1) works as follows. Before the direction finder starts, reference values of the primary spatial information parameters Δφ _{l, h} (f _v ) are calculated for the middle frequencies of all subranges

. The width of the subbands Δf _{v are} determined by the minimum bandwidth of the receiving paths of the direction finder. For this, a spatial description of the antenna array 5 is preliminarily carried out. For this purpose, the mutual distances between the antenna elements A _{l, h of the} array 5 (see Fig. 9) are measured when they are placed on a horizontal plane. In the general case (Z _{l, h} ≠ 0), the distances between the projections of the spatial arrangement of the AE on the horizontal plane passing through the first antenna element are used. In this case, for each AE, the values {Z _{l, h} } are additionally measured as {Z _{l, h} } = {Z _l } - {Z _h }. The measurement results on the bus 1 (see figure 1) are fed to the input of the unit for generating the reference values of PPIP 3. Here, according to the well-known algorithm (see Pat. RU No. 2283505, IPC 7 G01S 13/46, published on 09/10/2006, Bulletin No. 25; Pat. RU No. 2263328, published May 24, 2004, Bulletin No. 30) the values Δφ _{l, h, ET} (f _v ) are calculated, which are further stored in the first storage device 4 (see FIG. .3). Introduced declination Θ _flask antenna array 5 relative to the direction north, for example, as the angle between the vectors passing through the first and second AE and the center of the AP and the North direction.

In the process of operation of the direction finder using blocks from the 5th to the 18th (see figure 1), the search and detection of IRI signals in a given frequency band ΔF is performed. Received AR 5 signals at a frequency f _v are supplied to the corresponding inputs of the antenna switch 6. The task of the latter is to provide synchronous connection in a single time interval of any pairs of antenna elements to the reference and signal outputs. As a result, in sequence in time, both signal inputs of the two-channel receiver 7 receive signals from all possible pairs of AE gratings 5 (see Fig. 9). At the same time, all AEs periodically act as signal and as reference ones (subject to the use of a fully accessible switch 6). This achieves the maximum set of statistics on the spatial parameters of the electromagnetic field.

The signals supplied to the inputs of the receiver 7, amplify, filter and transfer to an intermediate frequency, for example 10.7 MHz. From the reference and signal outputs of the intermediate frequency of the receiver 7, the signals are fed to the corresponding inputs of the analog-to-digital converter (ADC) 8, where they are synchronously converted to digital form. The obtained digital samples of the signals of the antenna elements A _l and A _h in block 8 are multiplied by digital samples of two harmonic signals of the same frequency, shifted relative to each other by π / 2. As a result, in block 8 four sequences of samples are formed (quadrature components of the signals from two antenna elements A _l and A _h ). To implement the necessary impulse response of digital filters in the ADC 8, the operation of multiplying the samples of each quadrature component of the signal by the corresponding samples of the time window is performed. The order of these operations is described in detail in Pat. RU No. 2263328 and Pat. RU No. 2283505.

At the final stage, in block 8, two complex sequences of samples are formed by pairwise combining the corresponding samples of the corrected sequences, which are fed to the inputs of a digital band-pass filter 9 made by two-channel. In the initial position, the passband of the filters 9 is set equal to the passband of the RPU 7.

получают две преобразованные последовательности, характеризующие спектры сигналов, принимаемых в АЭ А_l и А_h, а следовательно, и их мощностные и фазовые характеристики. Однако этого недостаточно для измерения Р_l,h(f_v) и Δφ_l,h(f_v) в парах антенных элементов A_l и А_h. Последнее предполагает вычисление функции взаимной корреляции сигналов в соответствии с выражениемThe signals from the outputs of the analog-to-digital converter 8 through a band-pass filter 9 are fed to the corresponding inputs of the Fourier transform unit 10. As a result of the operation performed in block 10, in accordance with the expression

receive the converted two sequences characterizing the signal spectrum received AE A _l and A _h, and hence their cardinality and phase characteristics. However, this is not enough to measure P _{l, h} (f _v ) and Δφ _{l, h} (f _v ) in pairs of antenna elements A _l and A _h . The latter involves the calculation of the cross-correlation function of the signals in accordance with the expression

where l, h = 1,2, ..., N, l ≠ h is the number of AEs. Based on it, Δφ _{l, h} (f _v ) is defined as

and the value of P _{l, h} (f _v )

These functions (9) and (10) are performed by the calculating unit PPIP 11. In the prototype device (see Pat. RU No. 2263327, IPC 7 G01S 3/14, publ. 10/27/2005, bull. No. 30, p. 10) the possibility of finding the PPIP in accordance with (9) and (10) in the same block 7 (prototype) was considered; however, in the future work only the values Δφ _{l, h} (f _v ) are declared. In the proposed device the measured values of Δφ _{l, h} (f _v) and P _{l, h} (f _v) next recorded pulse generator 2 respectively the second 12 and fifth 22 memory devices. This operation is repeated until the PPIP values for all possible combinations of AE pairs are recorded in these blocks. The execution of this operation corresponds to the formation of arrays of measured PPIP Δφ _{l, h, ISM} (f _v ) and P _{l, h} (f _v ) (see figures 4 and 5).

The main purpose of blocks 13, 14, 15, 16, 17 and 3, 4 is to assess the degree of difference between the measured parameters Δφ _{l, h, ISM} (f _v ) (see figure 4) from the reference values (see figure .3), calculated for all the directions of arrival of a signal ΔΘ _k and D b _c, and all Δf _v, (see. the expression 4). This operation is carried out in accordance with the algorithm shown in Fig.6, as follows. The reference values Δφ _{l, h, ET} (f _v ) stored in the memory 4 are fed to the input of the subtracted block 13. The measured values Δφ _{l, h, ISM} (f _v ) from the output of block 12 are received at the input of the subtracted block 13. The subtraction operation is carried out in strict accordance with the procedure for generating AE pairs. For example, from Δφ _{2.7, ISM} (f _v ), only the values Δφ _{2.7, ET} (f _v ) for all directions of the signal arrival ΔΘ _k and Δβ _{c are} subtracted in turn.

(см. фиг.7), па основе которых могут быть получены искомые параметры Θ и β. Эта операция осуществляется блоком 17 путем поиска минимальной суммы

в массиве данных

(см.фиг.7).In the next step, the differences obtained are squared in block 14. This operation is necessary so that all the results of the subtraction operation have a positive value. Otherwise, a situation could arise when the sum of the positive and negative differences (Δφ _{l, h, ISM} (f _v )) + (- Δφ _{l, h, ET} (f _v )) compensated each other. For squaring, each calculation result is multiplied by itself in block 14. The resulting difference squares are added to the first adder 15 and written to the third memory 16. As a result, a data array is generated in block 16

(see Fig. 7), on the basis of which the desired parameters Θ and β can be obtained. This operation is carried out by block 17 by searching for the minimum amount

in the data array

(see figure 7).

Preliminary measurements of the spatial parameters Θ _j and β _{i by the} next pulse of the generator 2 are copied to the storage device 18 and fed to the output buses of the direction finder 19 and 20.

The purpose of the blocks from the 21st to the 32nd, as well as the 9th, is to measure the width of the spectrum of the detected signals, their average frequencies and based on these data to provide the optimal (in the frequency domain) reception of the detected radiation to refine the obtained spatial values parameters Θ _j and β _i . This operation is carried out in parallel with the measurement of blocks Θ _j and β _{i by} blocks 3,4 and 12-17 to ensure a higher measurement speed.

в частотном поддиапазоне Δf_v. Этим же импульсом результаты вычислений

записываются в шестое запоминающее устройство 25. Задним фронтом импульса с выхода счетчика 21 обнуляется сумматор 22. В результате блок 22 готов к новому циклу вычисления суммарной мощности P(f_v+1).Purpose of blocks 22 and 23 is to ensure the calculation of the total power signal P (f _v) by summing the mutual power P _{l, h} (f _v) for all pairs of antenna elements (5). In block 23, the values P _{l, h} (f _v ) received at its input are sequentially summed from the output of block 22. Information from the output of block 22 to the input of side 23 is transmitted by pulses of generator 2. After the arrival of η clock pulses (which corresponds to the number of processing pairs AE) at the output of block 23, the value of the total power P (f _v ) is formed for the subband Δf _v , the value of which is fed to the information input divided by η (block 24). The leading edge of the control pulse generated at the output of the pulse counter 21 in block 24 performs the operation of division by η (6), which corresponds to the calculation of the average signal power

in the frequency subband Δf _v . The same impulse results of calculations

are recorded in the sixth memory 25. The trailing edge of the pulse from the output of the counter 21 resets the adder 22. As a result, block 22 is ready for a new cycle of calculating the total power P (f _{v + 1} ).

для всех частотных поддиапазонов. Значения средней мощности

последовательно поступают на вход первого блока сравнения 26 (под воздействием импульсов с выхода счетчика 21). В случае превышения текущим значением

порогового уровня Р_ПОР на выходе блока 26 формируется управляющий импульс, разрешающий прохождению информации с выхода счетчика 28 на адресный вход запоминающего устройства 18. В результате записанное по этому адресу v, v=1,2,...,V; измеренное значение пеленга Θ_j поступает на вход второго блока сравнения 32. Назначение блоков 31 и 32 состоит в том, чтобы измерить ширину спектра пеленгуемых сигналов. В качестве критерия принадлежности излучения к одному источнику в предлагаемом устройстве использовано примерное равенство значений пеленгов Θ_j (см. фиг.8). Вновь пришедшее значение пеленга Θ_j с выхода блока 18 сравнивается в блоке 32 с предшествующим значением. В случае принятия положительного решения на первом выходе блока 32 формируется импульс, поступающий на счетный вход счетчика 31 увеличивая его содержимое на единицу. В результате код числа m в блоке 31 позволяет определить ширину спектра сигнала как Δf_ci=Δf×m. Значение m с выхода счетчика 31 поступает на информационные входы блока измерения средней частоты сигнала 30. В случае отрицательного решения в блоке 32 на его втором выходе формируется управляющий сигнал, который обнуляет содержимое счетчика 31.During V similar iterations, values are written to block 25

for all frequency subbands. Average power values

sequentially fed to the input of the first comparison unit 26 (under the influence of pulses from the output of the counter 21). In case of exceeding the current value

a threshold level P _POR at the output of block 26, a control pulse is generated that allows information to pass from the output of counter 28 to the address input of memory 18. As a result, v, v = 1,2, ..., V; the measured value of the bearing Θ _{j is} fed to the input of the second comparison unit 32. The purpose of the blocks 31 and 32 is to measure the width of the spectrum of the direction-finding signals. As a criterion for the belonging of radiation to one source in the proposed device, the approximate equality of the bearings Θ _j values is used (see Fig. 8). The newly arrived bearing value Θ _j from the output of block 18 is compared in block 32 with the previous value. If a positive decision is made, a pulse is generated at the first output of block 32, which arrives at the counting input of the counter 31, increasing its content by one. As a result, the code number m in block 31 to determine the width as the signal spectrum Δf _ci = Δf × m. The value of m from the output of the counter 31 is fed to the information inputs of the measuring unit of the average frequency of the signal 30. In the case of a negative decision in block 32, a control signal is generated at its second output, which resets the contents of the counter 31.

обнаруженного ИРИ в соответствии с (7) используя информацию о его граничной частоте

и ширине спектра Δf_ci, поступающую с выходов счетчиков импульсов 28 и 31 соответственно.The function of block 31 includes determining the average frequency of the signal spectrum

detected by IRI in accordance with (7) using information about its cutoff frequency

and spectrum width Δf _ci output of the pulse outputs of counters 28 and 31, respectively.

поступают на управляющий вход цифрового полосового фильтра 9 и вход управления приемником 7. Последний настраивается на частоту

, а в цифровом полосовом фильтре в обеих каналах формируется полоса пропускания Δf_ci.The measured values of Δf _ci and

arrive at the control input of the digital band-pass filter 9 and the control input of the receiver 7. The latter is tuned to the frequency

, and in the digital band-pass filter, a passband Δf _ci is formed in both channels.

Further direction finder operation is carried out according to the algorithm described above. The adjusted values of the spatial parameters Θ and β are supplied to the output buses 19 and 20 of the device.

The device that implements the proposed method uses known elements and blocks described in the scientific and technical literature.

Implementation options for antenna elements and antenna array 5 are widely considered in the literature (see Saidov A.S. et al. Design of phase automatic direction finders. - M .: Radio and communications, 1997; Torrieri DJ Principles of military communications system. Dedham / Massachusetts. Artech House, inc., 1981. - 298 p.). For the inventive direction finder, it is advisable to use one of the widely known types of antennas: symmetric and asymmetric vibrators (volume vibrators), discus antennas, biconical antenna elements, etc. The choice of antenna elements is determined by the given frequency range ΔF (overlap coefficient), design features of the antenna array. In general, the placement of AEs in the horizontal and vertical planes can be arbitrary. AE spacing in the vertical plane improves the accuracy of the direction finder when measuring Δβ. The number of used antenna elements N and the distance between them are determined by the specified accuracy of measuring spatial parameters, the range of operating frequencies ΔF and the effect of mutual influence of AE on each other. The latter determines the minimum distance between the AE lattice 5.

To ensure the highest and equal direction finding accuracy from all directions, it is advisable to use AR 5 with a ring (elliptical) AE placement (see Kukes I.S., Starik M.E. Fundamentals of radio direction finding. - M .: Sov. Radio, 1964. - 640 s.) With the maximum possible radius and height spacing.

An important aspect of the implementation of the AR 5 is the implementation of the coefficient of overlap K _PER frequency range. In cases where K _PER is set equal to 10 or more, a transition to the use of AR with a double or more ring structure is necessary.

An analysis of the dependence of the number of AE N and K _PER (according to the level of mutual influence of AE in the lower part of the frequency range and the ambiguity of the estimates obtained in its upper part) showed that in order to eliminate negative phenomena and their influence on the direction finding accuracy at K _PER = 10, it is necessary to have at least 8 AEs together with a fully accessible antenna switch and more than 14 AEs when using a partially accessible switch (see Pat. RU 2263328, publ. 10.27.2005, bul. No. 30).

Antenna switch (AK) 6 provides a synchronous connection in a single period of time any pairs of AE to the reference and signal outputs. The implementation of AK 6 is widely known (see Veniaminov V.N. et al. Microcircuits and their application. - M .: Radio and communications, 1989. - 240 s .; Vaysblat A.V. Microwave switching devices on semiconductor diodes. - M .: Radio and communications, 1987. - 120 p.).

Two-channel receiver 7 can be implemented using two ICOM semi-professional receivers IC-R8500 (see Communication Receiver IC-R8500. Instruction Manual). In this case, the first and second local oscillators of one of the receivers are used simultaneously as the first and second local oscillators, respectively, of the second receiver. In addition, other ICOM receivers can be used in pair as receiver 7: IC-R7000, IC-PCR1000.

A two-channel analog-to-digital converter 8, a digital band-pass filter 9 and a Fourier transform unit 10, as well as a PPIP calculation unit 11 and a second storage device 12 are implemented using standard boards: the ADMDDC2WB and ADP60PCI v.3.2 digital reception submodule on the Shark ADSP-21062 processor. User manual (see e-mail: insvs@arc.ru www-server www.insys.ru). The ADMDDC2WB submodule implements the functions of block 8 and contains DIGITAL DOWN CONVERTER (DDC) AD6620 microchips from Analog Devices for extracting part of the frequency band from the wide input signal band at the intermediate frequency of 10.7 MHz of receiver 7 of the IC-R8500, converting this band into a modulating frequency band and its output in quadrature, this operation is carried out by multiplying the digitized signal by the quadrature reference oscillation of the internal DDC generator.

The digital reception module ADMDDC2WB is used in carrier boards of the ADP6015A, ADP60PCI, ADP62PCI type. The basic module based on the ADP60PCI v.3.2 board on the Shark ADSP-21062 processor implements the discrete Fourier transform function (block 10), the operation of multiplication by a complex conjugate pair of channel samples (block 10), a digital band-pass filter (block 9), and finding the phase difference signals Δφ _{l, h, ISM} (f _v ) and P _{l, h} (f _v ) (block 11), as well as storing the measured values of the phase differences (block 12).

The first and second adders 15 and 23, respectively, and the subtraction block 13 are implemented according to well-known schemes (see Red E. Reference manual on high-frequency circuitry: Circuits, blocks, 50 ohm technology: Translated from German - M .: Mir, 1990. - 256 p.).

The first, third, fifth and sixth storage devices 4, 16, 22, 25, respectively, are buffer storage devices (see. Large integrated circuits of storage devices: Reference book / A.Yu. Gordenov et al. - M .: Radio and communications, 1990. - 288 p .; O. Lebedev, Memory microcircuits and their application. - M.: Radio and communications, 1990. - 160 p.).

The multiplier 14 implements the operation of squaring, and its implementation is covered in the book of Red E. Reference manual on high-frequency circuitry: Circuits, blocks, 50-ohm technique: TRANS. with him. - M.: Mir, 1990 .-- 256 p.

The unit for the formation of a reference set of primary spatial information parameters 3 is intended for creating tables of reference values of phase differences Δφ _{l, h, ET} (f _v ) for various pairs of antenna elements, l, h = 1,2, ..., N; l ≠ h, different sub-bands of frequencies v and different directions of the signal ΔΘ _k and Δβ _c , with a given discreteness, k = 1,2, ..., K; K × ΔΘ _k = 2π; c = 1,2, ..., C; C × Δβ _c = π / 2. At the preparatory stage, the following initial data are set on the first installation bus 1:

- azimuth processing sector {Θ _min , Θ _max };

- viewing sector in elevation {β _min , β _max };

- the accuracy of finding the angular parameter ΔΘ _k ;

- the accuracy of finding the elevation parameter Δβ _c ;

- placement topology antenna elements {d _{l, h};}

- spacing of the antenna elements in the vertical plane {Z _{l, h} };

- the frequency range ΔF, the width Δf and the middle frequencies {f _v } of the subbands.

The quantities {Θ _min, Θ _max} and {β _min, β _max} depend on the relative location finder control zone. The accuracy of finding the angular parameters ΔΘ _k and Δβ _c . ultimately determined by the specified direction finding accuracy, the location of the direction finder relative to the control zone and is limited by instrumental accuracy. The latter, in turn, is determined by the type (size and geometry) of the AP 5 used, AE characteristics, frequency range ΔF, radio wave propagation conditions, type of signal modulation, etc. The task of block 3 is that for a given direction finder, each frequency subband Δf _{v of a} given topology AR 5 with discreteness in azimuth ΔΘ _k and elevation angle Δβ _c , calculate ideal (reference) values of phase differences for all possible pairs of antenna elements Δφ _{l, h, ET} (f _v ).

Block 3 can be made in the form of an automaton based on the high-performance 16-bit microprocessor K1810 VM86 (see Veniaminov V.N. et al. Chips and their application: Reference manual. - 3rd ed., Revised and additional - M .: Radio and communications, 1990. - 512 p.) And working in accordance with the algorithm shown in Fig.10.

The fourth storage device 18 is a two-channel buffer storage device, the implementation of which is known (see Large Integrated Circuits of Storage Devices: Reference Book / A.Yu. Gordenov et al. - M.: Radio and Communications, 1990. - 288 p .; Lebedev O. N. Chips of memory and their application. - M.: Radio and communications, 1990. - 160 p.).

The construction of a clock generator 2 is known and widely covered in the literature (Radio receivers: a manual for radio engineering. Special. Universities / Yu.T. Davydov et al. M .: Higher school, 1989. - 342 p .; Functional units of adaptive interference cancellers : Part II. V.V. Nikitchenko. - L .: YOU.-1990. - 176 p.).

The implementation of the first, second and third pulse counters 21, 28 and 31 does not cause difficulties. They can be implemented on TTL series microcircuits, for example 155IE2 (see the Handbook of Integrated Circuits / B.V. Tarabrin et al. / Ed. By B.V. Tarabrin; 2nd ed., Revised and additional - M .: Energy, 1980 .-- 816 p.). The required capacity of the blocks, respectively, η, V, and M is provided due to the serial connection of the required number of chips 155IE2.

The implementation of the unit for determining the azimuth and elevation angle 17 is known and widely covered in the literature. It, as well as the prototype device, is designed to search for the minimum value of the sum of squared residuals (see expression 4). Block 17, it is advisable to implement the pyramid scheme using high-speed comparators (see. Shevkople BV Microprocessor structures. Engineering solutions: Handbook. 2nd ed. Revised and ext. - M .: Radio and communications, 1990. - 512 p. .).

The implementation of comparison blocks 26 and 32 is known and widely reported in the literature, they can be implemented on comparators (see. Shevkoples B.V. Microprocessor structures. Engineering solutions: Handbook. 2nd ed. Revised and enlarged. - M .: Radio and Communication, 1990. - 512 p.).

The block of “I” elements can be implemented by a set of elementary logic based on TTL-series microcircuits, for example, 155 or 133 series, the number of “I” elements used is determined by the value of the number V (counter capacity 28). At the same time, the first inputs of all “AND” elements are combined and connected to the output of the first comparison unit 26 (see the Handbook of Integrated Circuits / B.V. Tarabrik, S.V. Yakubovsky, N.A. Barkanov, etc.; Ed. B.V. Tarabrina, 2nd ed., Revised and enlarged - M .: Energia, 1980 .-- 816 p.).

(7) используя информацию, поступающую с выхода блока 28. Блок 30 может быть реализован на регистрах сдвига (микросхемах ТТЛ-й серий) как при выполнении первой, так и второй функции. Следует отметить, что наиболее предпочтительной является реализация блоков 18-го и с 25-го по 32-ой в виде автомата на базе высокопроизводительного микропроцессора, например, К1810 ВМ86 (см. Вениаминов В.Н. и др. Микросхемы и их применение: Справочное пособие. - 3-е изд., перераб. и доп. - М.: Радио и связь, 1990. - 512 с.). Алгоритм работы такого автомата приведен на фиг.11. Здесь величина ДО обозначает допустимое значение дисперсии оцениваемого параметра Θ.The implementation of the side to determine the average frequency of the signal 30 is known and does not cause difficulties. The main purpose of the block is the implementation of expression (7). In block 30, the operation of dividing by two numbers "m", coming from the output of block 31, and converting the obtained value to the value of the carrier frequency

(7) using the information received from the output of block 28. Block 30 can be implemented on shift registers (TTL series chips) both when performing the first and second functions. It should be noted that the most preferred is the implementation of the blocks of the 18th and from the 25th to the 32nd in the form of an automaton based on a high-performance microprocessor, for example, K1810 VM86 (see Veniaminov V.N. et al. Chips and their application: Reference allowance. - 3rd ed., revised and enlarged. - M.: Radio and Communications, 1990. - 512 p.). The operation algorithm of such an automaton is shown in Fig. 11. Here, the DO value indicates the allowable value of the variance of the estimated parameter Θ.

Claims (2)

1. A method for direction finding of radio signals, including receiving radio signals in the corresponding frequency subband Δf _v , Δf _v ∈ΔF, v = 1,2, ... V, V = ΔF / Δf, an antenna array consisting of N identical non-directional antenna elements, where N> 2, located in the direction-finding plane and locally adapted to local conditions, the sequential synchronous conversion of high-frequency signals of each pair of antenna elements of the antenna array into electrical signals of intermediate frequency, their discretization and quantization, the formation of four ex sequences of samples by dividing into quadrature components, storing in each sequence a given number of samples of quadrature components of the signals, correcting the stored samples of sequences of quadrature components by sequentially multiplying each of them by the corresponding sample of a given time window, generating from the corrected sequences of quadrature components of the samples of signals of two complex sequences of samples of signals, elements of a cat ryh determined by pairwise combining respective samples of the corrected sequence of quadrature component signals of the antenna elements, the conversion of both complex sequences of signals using the discrete Fourier transform, pairwise multiplying the samples of signal samples of the transformed sequence of one antenna element A ₁ corresponding complex conjugate samples of the transformed sequence of the signal at the same frequency another antenna element And _h , where 1, h = 1,2, ... M, 1 ≠ h, calculation for the current pair of antenna elements of the phase difference of the signals for each frequency subband according to the formula Δφ _{l, h, ISM} (f _v ) = arctan (U _c (f _v ) / U _s (f _v )), storing the obtained phase differences of the radio signals, generating and storing the reference set of phase differences of the signals based on the spatial arrangement of the antenna elements of the antenna array, the frequency range used and the given measurement accuracy, subtracting the corresponding values of the measured phase differences from the reference phase differences of the signals, erection squared floor values of the residuals and summing them over all pairs of antenna elements and all frequency subbands, storing the sums obtained that are in unambiguous correspondence with the directions of arrival of the radio signals, determining the most probable direction of the arrival of the radio signal in horizontal and elevation planes from the smallest sum of squared residuals, characterized in that in addition, for each pair of antenna elements and each subband, the values of the mutual power of the signals P _{1, h} (f _v ) are calculated by the formula P _{l, h} (f _v ) = | U _c (f _v ) U _s · (f _v ) |, the obtained values of the mutual power P _{1, h} (fv) are stored, the total power of the signals P (f _v ) is determined by summing the mutual powers over all pairs of antenna elements for each frequency subband Δf _v , the values of the total signal power are stored, calculate the average value of the signal power P (fv) in each frequency subband according to the formula P (f _v ) = P (f _v ) / η, where η is the number of antenna pairs used in processing, determine the frequency subbands Δf _v ', in which the average value signal power exceeds a predetermined threshold P _POR , the values of the bearings corresponding to the subbands Δ _v 'are stored, the width of the spectra of the signals Δf _ci is determined by the number m, m = 1,2, ..., M of adjacent bearings Θ _{j of the} same name using the formula Δf _ci = Δf · m, the average value is determined signal frequency f _ci for all detected emissions according to the formula

me

- the upper frequency range i-th signal, jointly storing average values of signals of frequencies f _ci and corresponding Δf _ci bandwidth successively over the entire range ΔF isolated Δf _ci baseband suppressing interfering signals and clarify the most likely direction of arrival of radio signals in the horizontal and vertical planes . 2. A direction finder comprising an antenna array made up of N> 2 identical omnidirectional antenna elements located in the direction-finding plane and locally adapted to local conditions, an antenna switch, N inputs of which are connected to the corresponding N outputs of the antenna array, and the signal and reference outputs of the switch connected respectively to the signal and reference inputs of a two-channel receiver, made according to the scheme with common local oscillators, an analog-to-digital converter, made by two-channel respectively respectively, with the signal and reference channels, the signal and reference outputs of the intermediate frequency of the two-channel receiver being connected respectively to the signal and reference inputs of the analog-to-digital converter, the Fourier transform unit, made two-channel, respectively, with the signal and reference channels, the first and second memory devices, the subtraction unit, a unit for generating reference values of phase differences, a unit for calculating primary spatial information parameters, the first information input of which is it is single with the signal output of the Fourier transform block, and the second input is with the reference output of the side of the Fourier transform, the first group of information outputs of the calculation unit of the primary spatial information parameters is connected to the group of information inputs of the second storage device, the group of information outputs of which is connected to the group of inputs of the subtracted subtraction block , the group of inputs of which is reduced which is connected to the information outputs of the first storage device, the information inputs of which are integrated with the information outputs of the unit for generating the phase difference reference values, the group of information inputs of which is the first mounting bus of the direction finder, the multiplier connected in series, the first adder, the third storage device, the azimuth and elevation unit, and the first and second groups of information inputs of the multiplier are combined and connected with a group of information outputs of the subtraction unit, a clock generator, the output of which is connected to the control input of the antenna switch, in synchronization odes of the analog-to-digital converter, the Fourier transform unit, the first, second and third storage devices, the subtraction unit, the multiplier, the first adder, the azimuth and elevation determination unit, the phase difference reference unit generation unit, and the primary spatial information parameter calculation unit, the fact that additionally introduced the fourth, fifth and sixth storage devices, the block of elements "And", the first, second and third pulse counters, the second adder, divider, the first and a second comparison unit, a unit for determining the average frequency of the signal and a digital bandpass filter, made two-channel, and the first and second signal inputs of the digital bandpass filter are connected to the outputs of the signal and reference channels of the analog-to-digital converter, respectively, and the first and second signal outputs are connected respectively to the signal and the reference inputs of the Fourier transform unit, the first counter, the fifth storage device, the second adder, the divider, the sixth storage the structure and the first comparison unit, and the counting input of the first pulse counter is combined with the synchronization inputs of the fifth memory device, the second adder, digital bandpass filter and the output of the clock generator, and the zeroing output of the first pulse counter is connected to the control inputs of the second adder and divider, synchronization inputs of the sixth memory devices and the first comparison unit, and the counting input of the second pulse counter, the group of information outputs of which are connected to the first group and formation inputs of the unit for determining the average frequency of the signal and with the corresponding second inputs of the block of elements "And", the first inputs of which are combined and connected to the output of the first block of comparison, and the outputs of the block of elements "And" are connected to the group of address inputs of the fourth storage device, the first and second groups the information inputs of which are connected to the first and second group of information outputs of the unit for determining the azimuth and elevation, and the first and second group of information outputs of the fourth storage device VA are respectively the first and second output buses of the direction finder, the second installation bus of which is connected to the second group of information inputs of the first comparison unit, the group of information inputs of the second comparison unit is combined with the second output bus of the direction finder, the first output of the second comparison unit is connected to the counting input of the third pulse counter, and the second output is with the zeroing input of the third pulse counter, the group of information outputs of which is connected to the second group of information inputs of the block EFINITIONS medium frequency signal, the group of information outputs of which is connected to the groups of the control inputs of the digital bandpass filter and a two-channel receiver.

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