RU2099838C1 - Adaptive antenna array - Google Patents

Abstract

FIELD: radio engineering and communications; radar and radionavigation systems, radio communication systems operating in noisy environment. SUBSTANCE: adaptive antenna array that has N antennas connected through complex weight multipliers to respective inputs of common adder, N adaptive circuits with control inputs whose first inputs are connected to outputs of respective antennas and second inputs, to output of common adder, and first outputs are connected to respective control inputs of complex weight amplifiers, is provided, in addition, with output power maximizing unit whose first and second inputs are connected, respectively, to first and second outputs of adaptive circuits and their outputs are connected to respective third inputs of adaptive circuits. EFFECT: improved noise immunity in receiving signals interrupted in the course of their transmission, such as pseudorandom working-frequency retuning signals. 2 cl, 12 dwg

Description

 The invention relates to the field of radio engineering and communications and can be used in radar, radio navigation and radio communication systems operating in a complex jamming environment, for example, in radio communication systems with moving objects.

 Known adaptive antenna array (AAR) circuits that implement an algorithm to maximize the output ratio of the useful signal power to the sum of the interference and noise powers (see R. A. Monzingo, T.U. Miller. Adaptive antenna arrays. Introduction to the theory. M. Radio and Communication, 1986, p. 80 86, 179 -240). For the operation of AAR of this type, a priori information is used on the direction of arrival of the useful signal. Therefore, AAR of this design is not applicable in radio systems where such information is not available (for example, in communication systems with moving objects).

 In TIIER, 1967, v. 55, N 12, p. 78 95, an AAR scheme is presented that implements an algorithm for minimizing the standard deviation of the received signal from the reference signal. For the algorithm to work in the device, it is necessary to form a reference signal. This is possible if there is a priori information about the useful signal. And since such information is never complete, since the meaning of the useful signal would be lost, the reference signal can significantly differ from the useful one, which causes a significant decrease in the AAR noise immunity.

 AAP, the construction of which is described in the journal IEEE Trans Antennas and Propag, vol. AP-26, 1978, N 2, p. 228-235, implements an algorithm for minimizing the output power and has relatively good noise immunity characteristics. However, in the case when there is no interference or its power is less than the power of the useful signal, the useful signal can be suppressed due to minimization of the total output power.

 Of the known AAPs, the lattice described in Auth. St. USSR N 1548820, class H 01 Q 21/00 (claimed on 10/13/87, published on 03/07/90 bull. N 9). This device contains N antenna elements connected through hybrid devices, and weight multipliers with the corresponding inputs of the common adder, the first multiplier and 2N adaptive circuits, each of which consists of an integrator, a switch, an amplifier, an adjustable inverting amplifier, a subtraction unit, a second multiplier and a correlator moreover, the first and second inputs of the correlator are connected respectively to the output of the hybrid device and the output of the common adder, and the output of the correlator is connected to the first input of the subtraction unit , the second input of which is connected to the output of the first multiplier, and the output of the subtraction unit is connected to the inputs of the amplifier and the adjustable inverting amplifier, the outputs of which are connected to the inputs of the switch, the output of which is connected via the integrator to the second input of the weight multiplier and to the first input of the second multiplier, and the second input the second multiplier is connected to the output of the first multiplier, the first and second inputs of which are combined with the output of the common adder and the second input of the correlator, as well as a signal power estimator, an estimator m interference sensitivity, a comparison unit and a control unit, the inputs of the units for evaluating the signal power and interference power are connected to the output of the common adder, and the outputs are connected to the inputs of the comparison unit, the output of which is connected to the control inputs of the switches, the output of the control unit is connected to the control inputs of adjustable inverted amplifiers , and the output is connected to the output of the interference power estimation unit.

 Depending on the signal-noise environment, the device operates by the method of minimizing or maximizing the output power, which prevents the suppression of the useful signal and increases the noise immunity of the grating.

However, this design of the AAR has several disadvantages:
increased noise immunity is provided only in relation to interfering signals whose frequency band and power exceeds the frequency band and the useful signal power;
AAR operation efficiency is significantly reduced in case of a slight excess of the interference power over the signal power at the input of antenna elements (AE);
in the case when the number of degrees of freedom of the grating exceeds the number of interference acting on its input and the signal power is less than the total interference power, minimizing the total output power of the AAR leads to suppression of not only interference, but also a useful signal, for example, when a useful signal is exposed to the input of a three-element grating and one interference, the AAR, minimizing the output power, generates two "zeros" of the radiation pattern: one in the direction of arrival of the interference, and the second in the direction of arrival of the signal.

 The aim of the invention is the development of AAR with higher noise immunity of receiving signals having a pause during transmission (for example, signals with pseudo-random tuning of the operating frequency (MHF)), in relation to interfering signals regardless of their frequency band and power at any signal-noise setting.

 This goal is achieved by the fact that in the well-known AAR containing N antenna elements connected via complex weight multipliers with the corresponding inputs of the common adder, adaptive circuits with control inputs, the first inputs of which are connected to the outputs of the corresponding antenna elements, the second inputs are connected to the output of the common adder, and the first outputs are connected to the corresponding control inputs of complex weight multipliers, an output power maximizing unit is introduced, the first and second inputs of which They are connected respectively to the first and second outputs of the adaptive circuits, and the outputs are connected to the corresponding third inputs of the adaptive circuits. The output power maximization unit consists of a switch, N first dividers, N storage devices, a first adder, N-1 complex conjugation blocks, N-1 first multipliers, N-2 second dividers, N-2 second adders, a regularization parameter formation unit , N second multipliers and N output adders, the outputs of the switch are connected to the first inputs of the corresponding first dividers, the second inputs of which are connected to the first output of the switch, the control input of which is connected to the control inputs of the storage devices TV, the inputs of which are connected to the outputs of the corresponding first dividers, the output of the first storage device being connected to the first input of the first adder, and the outputs of the remaining storage devices connected to the inputs of the complex conjugation blocks, with the first inputs of the first multipliers and with the first inputs of the corresponding second multipliers, the outputs of the blocks integrated interfaces are connected to the first inputs of the corresponding second multipliers, to the second inputs of the first multipliers, the outputs of which are paired to the first and second the input inputs of the corresponding second dividers, the outputs of which are connected to the first inputs of the second adders, the second inputs of the first and second adders connected to the output of the regularization parameter generation unit, and the outputs of the first adder and second adders connected to the first inputs of the corresponding second multipliers, the outputs of which are connected to the inputs the corresponding output adders, and the inputs of the switch, the second inputs of the second multipliers and the control input of the switch are respectively the first, second and ravlyaetsya inputs and the outputs of adders outputs maximizing signal power unit.

 Thanks to the introduction of an output power maximizing unit into the AAP circuit, a higher noise immunity of receiving signals having a pause during transmission (for example, signals with pseudo-random tuning of the operating frequency (PFC)) is achieved with respect to interfering signals regardless of their frequency band and power at any signal-jamming environment.

The inventive device is illustrated by drawings, in which:
in FIG. 1 shows a functional diagram of the AAR;
in FIG. 2 block diagram of adaptive circuits;
in FIG. 3 diagram of a signal power maximization unit as applied to a three-element AAR;
in FIG. 4 adder circuit;
in FIG. 5 integrator circuit;
in FIG. 6 switch circuit;
in FIG. 7 switch circuit;
in FIG. 8 diagram of a block for generating a regularization parameter;
in FIG. 9 diagram of a subtraction block;
in FIG. 10 scheme of the multiplier (divider);
in FIG. 11 diagram of a complex pairing unit;
in FIG. 12 AAR simulation results.

 The inventive device shown in FIG. 1, consists of a block of antenna elements 1, a block of complex weight multipliers 2, a total adder 3, N blocks of adaptive circuits 4 with control inputs, a block of maximizing signal power 5 with a control input, and the outputs of N complex weight multipliers of a block of complex weight multipliers 2 are connected to N inputs of a common adder, the output of which is the output of AAP, the first inputs of N adaptive circuits 4 are connected to the outputs of N antenna elements of the unit of antenna elements 1, the second inputs of adaptive circuits 4 are connected to the output of the common adder 3, and the first outputs of the adaptive circuits 4 are connected to the corresponding control inputs of the complex weight multipliers of the block of complex weight multipliers 2, N of the first and N second inputs of the output power maximization unit to the first and second outputs of the corresponding adaptive circuit 4 blocks, and N outputs of the output maximize block power 5 connected to the third inputs of the respective blocks of adaptive circuits 4.

 The adaptive loop unit 4 shown in FIG. 2, consists of: an integrator 4.1, multipliers 4.2 and 4.3, a switch 4.4, an inverting amplifier 4.5, an amplifier 4.6, a subtraction unit 4.7, a correlator 4.8, the first and second inputs of the correlator 4.8 being connected respectively to the output of the block of antenna elements 1 and the output of the common adder 3 and the output of the correlator 4.8 is connected to the first input of the subtracting unit 4.7, the second input of which is connected to the output of the first multiplier 4.2, and the output of the subtracting unit is connected to the inputs of the amplifier 4.6 and inverting amplifier 4.5, the outputs of which are connected respectively to the corresponding the second input of the signal power maximizing unit 5 and the first input of the switch 4.4, the control input of which is connected to an external device, the second input is connected to the corresponding output of the signal power maximizing unit 5, and the output through the integrator 4.1 is connected to the corresponding second input of the complex weight multiplier 2 and with the first input of the first multiplier 4.2, and the second input of the first multiplier 4.2 is connected to the output of the second multiplier 4.3, the first and second inputs of which are combined with the output of the common adder 3 and the second correlator 4.8.

 The output power maximizing unit 5 shown in FIG. 3, consists of: a switch 5.1, N first dividers 5.2, N storage devices 5.3, a first adder 5.4, N-1 blocks of complex conjugation 5.5, N-2 second dividers 5.7, N-2 second adders 5.8, a block for generating a regulation parameter 5.9, N • N second multipliers 5.10 and N output adders 5.11, with the first outputs of the adaptive circuit blocks 4 through a switch 5.1, the control input of which is connected to an external device, connected to the first inputs of the first dividers 5.2, the second inputs of which are connected to the first output of the switch 5.1, and outputs connected to input am of storage devices 5.3, wherein the output of the first storage device is connected to the first input of the first adder 5.4, and the outputs of the remaining storage devices are connected to the inputs of the complex conjugation blocks 5.5, to the first inputs of the first multipliers 5.6 and to the first inputs of the corresponding second multipliers 5.10, the outputs of the complex conjugation blocks 5.5 are connected to the first inputs of the corresponding second multipliers 5.10 and to the second inputs of the first multipliers 5.6, the outputs of which are paired to the first and second inputs respectively second dividers 5.7, the outputs of which are connected to the first inputs of the second adders 5.8, and the second inputs of the first 5.4 and second 5.8 adders are connected to the output of the regularization parameter generation unit 5.9, and the outputs of the first adder 5.4 and second adders 5.8 are connected to the first inputs of the corresponding second multipliers 5.10, the second inputs of which are connected to the corresponding second outputs of the blocks of adapted circuits 4, and the outputs are connected to the inputs of the corresponding output adders 5.11, the outputs of which are connected to the third inputs of the corresponding etstvuyuschih adaptive circuits 4.

 As an external device, control signal generating devices are used (the place for generating the control signal is outside the AAR and depends on the particular radio engineering system. For example, for radio communication systems with pseudo-random tuning of the operating frequency, the control signal can come from the frequency synthesizer when the receiver is tuned to a different frequency, when there is no useful signal at a given frequency).

 The block of complex weight multipliers 2 consists of N complex weight multipliers (see R.A. Monzingo, T.U. Miller. Adaptive antenna arrays. Introduction to the theory. M. Radio and Communications, 1986, p. 56).

 Adders 3, 5.4, 5.8 and 5.11 can be made in the form of high-frequency transformers on coaxial or microstrip lines depending on the frequency range (figure 4). The integrator 4.1 can be made in the form of a capacitor or a set of capacitors (for example, a chip K228HE1) discharged by an electromagnetic relay (figure 5) or an electronic key (for example, a diode key K228KH1). As the switches 4.4 and 5.1 can be used electromagnetic relays (Fig.6 and Fig.7, respectively) or electronic switches on microcircuits K155KP5. Correlator 4.8 can be made in the form of a multiplier. Storage devices 5.3 can be made in the form of capacitors or a set of capacitors (for example, K228NE1 chip) discharged by electromagnetic relays (Fig. 5) or electronic keys (for example, K228KN1 diode key) as applied to analog circuits, or on random-access memory chips (for example , chip K155ZU3) as applied to digital circuits. The regularization formation block 5.9 can be made in the form of a voltage divider (Fig. 8) as applied to analog circuits, or as a permanent storage device (for example, K155RE3 chip) as applied to digital circuits. As an inverting amplifier 4.5, an amplifier stage on a bipolar transistor connected according to a common emitter circuit with negative coupling can be used (see the Handbook of Radio-Electronic Devices. In 2 volumes. T.1. Burin L.P. Vasiliev V. P. Kaganov V.I. et al. Edited by D.P. Linde, M. Energia, 1978, p. 33, Fig. 1-30), and as an amplifier 4.6, an emitter follower on a biopolar transistor can be used ( see ibid., p. 41, fig. 1-41a). The subtraction unit 4.7 can be made in the form of a high-frequency transformer on coaxial or microstrip lines (depending on the frequency range) with the oncoming primary windings turned on (Fig. 9). The multipliers 4.2, 4.3, 5.6, 5.10 and the correlator 4.8 can be made in the form of the circuit shown in figure 10, moreover, as amplifiers 1 and 2, an amplifier stage is used on a biopolar transistor connected according to a common emitter circuit with negative feedback ( see the Handbook of electronic devices. In 2 volumes. T. 1. Burin LI Vasiliev VP Kaganov VI and others Edited by D.P. Linde. M. Energy, 1978, p. 33, Fig. 1-30), an emitter follower on a bipolar transistor was used as amplifier 3 (see ibid., p. 41, Fig. 1-41a), and as an electronic att nyuatora used electronic attenuator transistor (ibid., p. 75, ris.1-88b). The dividers 5.2, 5.7 can be made in the form of the circuit shown in figure 10, moreover, as amplifiers 1, 2 and 3, an amplifier stage is used on a bipolar transistor connected in a circuit with a common emitter, with negative feedback (see. Reference to electronic In 2 volumes, T.1, Burin, L.I., Vasiliev, V.P. Kaganov, V.I., et al., Edited by D.P. Linde, M. Energia, 1978, p. 33, fig. .1-30), and an electronic attenuator on a transistor was used as an electronic attenuator (see ibid., P. 75, Fig. 1-88b). Integrated interface blocks 5.5 can be made in the form of signal decomposition schemes into in-phase and quadrature components with the inclusion of an additional phase shifter in π of Fig. 11 in the quadrature branch.

 In addition, the adaptive circuit blocks 4 and the output power maximization unit 5 can be performed on a digital signal processor, for example, the TMS320C30 chip (Digital signal processing processors. Reference book. A. G. Ostapenko, S. I. Lavinsky, A. B. Sushkov et al. Edited by A.G. Ostapenko, M. Radio and Communications, 1994, p. 88).

 Adaptive antenna array operates as follows.

 The radio signals are received by the antenna elements 1, weighed by complex weight multipliers 2 and summed in the total adder 3, the output of which is the output of the device. Using adaptive circuits 4 and a signal power maximizing unit 5, complex weight multipliers 2 are set up to increase the signal / (noise + noise) ratio at the output of the device. Setup is carried out in two stages. At the first stage, in the absence of a useful signal by adaptive circuits 4, the AAP output power is minimized (the signal power 5 maximization unit is not involved). As a result, the directivity pattern of the AAR with “zeros” in the direction of interference arrival is formed. At the second stage, in the presence of a useful signal by the adaptive circuits 4 and the signal power maximizing unit 5, the output power of the AAR is maximized taking into account the “zeros” of the directivity characteristics of the AAR obtained in the first stage. In order to prevent inadvertent suppression of the useful signal, the maximization of the output power of the AAR is carried out by a regularized recursive algorithm. Switching the operating modes of the AAR is carried out using the control signal (the place of formation of the control signal is outside the AAR and depends on the particular radio system. So, for example, for radio communication systems with pseudo-random tuning of the operating frequency, the control signal can come from the frequency synthesizer when the receiver is tuned to another frequency, when there is no useful signal at this frequency) by switches 4.4 and 5.1. Storing the parameters of the directivity characteristics of the AAR formed at the first stage (minimizing the output power in the absence of a useful signal) is carried out by the storage devices 5.3.

 In the absence of a useful signal at the AAP input, the control signal "No useful signal" is received to the control inputs of the adaptive circuits 4 and the signal power maximizing unit 5. By this command, the switch 5.1 of the power maximizing unit 5 disconnects the first inputs of the power maximizing unit from the adaptive circuits 4, and the switches 4.4 of the adaptive circuits 4 transfer them to the mode of minimizing the output power of the device.

где

N-мерный вектор весовых коэффициентов (ВВК) ААР;

N-мерные векторы k-й помехи и теплового шума соответственно; N количество элементов ПФ; L число источников помех; E{ •} + обозначения операций математического ожидания и эрмитового сопряжения соответственно. Тогда оптимизационная задача минимизации выходной мощности будет иметь вид:

Решение задачи может быть получено градиентным методом (см.Compton R.T. Power optimization in adaptive arrays: a technique for interference protection// IEEE Trans, 1980, V.AP-28, N 1, pp.79 -85):

Реализация алгоритма (3) обеспечивается адаптивными контурами 4, в состав каждого из них входят: интегратор 4.1, умножители 4.2 и 4.3, коммутатор 4.4, инвертирующий усилитель 4.5, усилитель 4.6, блок вычитания 4.7, коррелятор 4.8, причем первый и второй входы коррелятора 4.8 соединены соответственно с выходом блока антенных элементов 1 и выходом общего сумматора 3, а выход коррелятора 4.8 соединен с первым входом блока вычитания 4.7, второй вход которого соединен с выходом первого умножителя 4.2, а выход блока вычитания подключен к входам усилителя 4.6 и инвертирующего усилителя 4.5, выходы которых подключены соответственно к соответствующему второму входу блока максимизации мощности сигнала 5 и к первому входу коммутатора 4.4, управляющий вход которого подключен к внешнему устройству, второй вход соединен с соответствующим выходом блока максимизации мощности сигнала 5, а выход через интегратор 4.1 соединен с соответствующим вторым входом блока комплексных весовых умножителей 2 и с первым входом первого умножителя 4.2, а второй вход первого умножителя 4.2 соединен с выходом второго умножителя 4.3, первый и второй входы которого объединены с выходом общего сумматора 3 и вторым входом коррелятора 4.8. При этом

вектор весовых коэффициентов на выходах интеграторов 4.1;

вектор входных сигналов на выходах антенных элементов 1; y(k)=

сигнал на выходе общего сумматора 3; μ коэффициент усиления в адаптивных контурах 4 (коэффициент усиления инвертирующих усилителей 4.5), а на выход коммутаторов 4.4 блоков адаптивных контуров 4 коммутируются первые входы.The power of the AAR output signal in the absence of a useful signal at its input, up to a constant factor, is determined by the expression (see R. A. Monzingo, T.U. Miller. Adaptive antenna arrays. Introduction to the theory. M. Radio and Communications, 1986 , p. 83):

Where

N-dimensional vector of weights (VVK) AAP;

N-dimensional vectors of the kth interference and thermal noise, respectively; N is the number of PF elements; L is the number of sources of interference; E {•} + designations of operations of mathematical expectation and Hermitian conjugation, respectively. Then the optimization problem of minimizing the output power will have the form:

The solution to the problem can be obtained by the gradient method (see Team RT Power optimization in adaptive arrays: a technique for interference protection // IEEE Trans, 1980, V.AP-28, N 1, pp. 79-85):

The implementation of algorithm (3) is provided by adaptive circuits 4, each of which includes: integrator 4.1, multipliers 4.2 and 4.3, switch 4.4, inverting amplifier 4.5, amplifier 4.6, subtraction unit 4.7, correlator 4.8, and the first and second inputs of correlator 4.8 are connected respectively, with the output of the unit of antenna elements 1 and the output of the total adder 3, and the output of the correlator 4.8 is connected to the first input of the subtraction unit 4.7, the second input of which is connected to the output of the first multiplier 4.2, and the output of the subtraction unit is connected to the inputs of the amplifier 4.6 and inverter amplifier 4.5, the outputs of which are connected respectively to the corresponding second input of the signal power maximizing unit 5 and to the first input of the switch 4.4, the control input of which is connected to an external device, the second input is connected to the corresponding output of the signal power maximizing unit 5, and the output through the integrator 4.1 is connected with the corresponding second input of the block of complex weight multipliers 2 and with the first input of the first multiplier 4.2, and the second input of the first multiplier 4.2 is connected to the output of the second multiplier 4.3, the first first and second inputs of which are combined to yield the total of the adder 3 and the second input of the correlator 4.8. Wherein

vector of weighting coefficients at the outputs of integrators 4.1;

vector of input signals at the outputs of the antenna elements 1; y (k) =

signal at the output of the total adder 3; μ is the gain in adaptive circuits 4 (gain of inverting amplifiers 4.5), and the first inputs are switched to the output of the switches 4.4 of the blocks of adaptive circuits 4.

При этом вектор весовых коэффициентов

ортогонален векторам помех

то есть определяют характеристику направленности ААР с нулями в направлении прихода помех.It can be shown (see Team RT Power optimization in adaptive arrays: a technique for interference protection // IEEE Trans, 1980, V. AP-28, N1, pp. 79-85) that for a quasistationary model of a signal-noise situation, the solution ( 2) and (3) there will be an eigenvector (CB) corresponding to the minimum eigenvalue (MF) l _{min of the} correlation matrix (CM) R _psh

Moreover, the vector of weights

orthogonal to interference vectors

that is, they determine the directivity characteristic of the AAR with zeros in the direction of arrival of interference.

If for a linear equidistant AAA we denote Z = e ^iΦ (Φ is the phase shift due to the delay of the signal at the output of the second AR element with respect to the first), then the directivity characteristic of the AAR can be represented as a normalized polynomial in algebraic and animated form, respectively (see Zhuravlev A.K. Lukoshkin A.P. Poddubny S.S. Signal Processing in Adaptive Antenna Arrays (L. Leningrad State University, 1983, p. 18)
f (Z) = Z ^N-1 + a ₁ Z ^N-2 + .a _N-2 Z + a _N-1 , (5)
f (Z) = (ZC ₁ ) (ZC ₂ ). (ZC _N-1 ), (6)
where C _{j are the} roots of the polynomial.

, а корни полинома C_j имеют вид e^iΦj и располагаются на единичной окружности в плоскости комплексной переменной Z. При этом положение C_j на единичной окружности однозначно определяют нуль XH направление прихода помехи.Obviously, the coefficients a _{j of} polynomial (5) coincide with the elements W _{j + 1} / W ₁ BBK

, and the roots of the polynomial C _j have the form e ^iΦ j and are located on the unit circle in the plane of the complex variable Z. Moreover, the position C _j on the unit circle uniquely determines zero XH direction of arrival of the noise.

(собственный вектор

), обеспечивающий, наряду с подавлением помех, максимальное усиление полезного сигнала. Данный ВВК является решением оптимизационной задачи

где R_xx= R_пш+R_cc; R_cc=

N-мерный вектор сигнала; C_j, C_j' корни полиномов, коэффициенты которых являются компонентами нормированных векторов

вектор, удовлетворяющий ограничениям задачи (7)).It can be proved that there is an infinite number of different values of the coefficients a _{j of} polynomial (5), which are solutions to problem (2) and provide the same values of the roots C _{j of} polynomial (6), therefore, there is an VVK

(eigenvector

), which provides, along with suppression of interference, the maximum gain of the useful signal. This IHC is a solution to the optimization problem

where R _xx = R _psh + R _cc ; R _cc =

N-dimensional signal vector; C _j , C _j 'are the roots of polynomials whose coefficients are components of normalized vectors

vector satisfying the constraints of problem (7)).

где A N•L матрица ограничений, состоящая из L N-мерных векторов

вектор ограничений; Φ_jl фазовый сдвиг j-й помехи на выходе i+1-го элемента ПФ по отношению к первому, тождественен ВВК, полученному в результате решения оптимизационной задачи (7). Справедливость этого утверждения непосредственно следует из того, что как ограничения

-С_j=0, так и ограничения

определяют ХН ААР с нулями в направлениях прихода помех, то есть

принадлежит пространству, базисом которого являются линейно-независимые векторы

.The solution to problem (7) can be obtained using the method of uncertain Lagrange multipliers. However, the algorithms obtained are complex and non-constructive. Therefore, instead of the VVK obtained as a result of solving the optimization problem (7), we can use the vector of weight coefficients obtained as a result of solving the optimization problem

where AN • L is a constraint matrix consisting of L N-dimensional vectors

constraint vector; Φ _{jl the} phase shift of the j-th noise at the output of the i + 1-st element of the FS with respect to the first is identical to the VVK obtained by solving the optimization problem (7). The validity of this statement directly follows from the fact that as limitations

-C _j = 0, and restrictions

determine AH AAR with zeros in the directions of arrival of interference, i.e.

belongs to a space whose basis are linearly independent vectors

.

где P=1-A(A⁺)^-1A⁺ проектор на линейное многообразие, порожденное решением системы

Выражение (9) реализует условнооптимальную обработку максимизацию мощности сигнала при полном подавлении помех.An algorithm for calculating VVK, which provides the solution to problem (8), was synthesized using the projection method (see Karavaev V.V. Sazonov V.V. Statistical Theory of Passive Location. M. Radio and Communications, 1987, pp. 27-28)

where P = 1-A (A ⁺ ) ^-1 A ^{+ is the} projection onto the linear manifold generated by the solution of the system

Expression (9) implements conditionally optimal processing to maximize the signal power while completely suppressing interference.

 As a projector P, it is advisable to use a matrix whose column space will be orthogonal to the interference vectors, i.e.

При этом проектор Р может быть восстановлен по любому из собственных векторов

и применительно к линейной эквидистантной ААР представлен в виде

где

первый элемент вектора

b_jj коэффициенты, определяемые из условия тождественности корней алгебраических полиномов f₁(Z)-f_N-1(Z), коэффициентами которых являются составляющие нормированных векторов

, * обозначение операции комплексного сопряжения. Можно показать, что применительно к линейной эквидистантной ААР коэффициенты b_jj определяются из уравнения
b_jj = (W₁(j)W $\genfrac{}{}{0ex}{}{\text{*}}{\text{1}}$ (j))/(W₁(N)W $\genfrac{}{}{0ex}{}{\text{*}}{\text{1}}$ (N)), (12)
где W₁(j) j-й элемент вектора

.

In this case, the projector P can be restored by any of the eigenvectors

and in relation to linear equidistant AAP is presented in the form

Where

first element of vector

b _jj coefficients determined from the identity condition for the roots of algebraic polynomials f ₁ (Z) -f _N-1 (Z), the coefficients of which are the components of normalized vectors

, * designation of the operation of complex pairing. It can be shown that in relation to a linear equidistant AAP, the coefficients b _{jj are} determined from the equation
b _jj = (W ₁ (j) W $\genfrac{}{}{0ex}{}{\text{*}}{\text{one}}$ (j)) / (W ₁ (N) W $\genfrac{}{}{0ex}{}{\text{*}}{\text{one}}$ (N)), (12)
where W ₁ (j) is the jth element of the vector

.

Вследствие того, что действие операторов F_1j заключается в перестановке и комплексных сопряжениях компонент вектора

а собственно

определяется с использованием выходного сигнала ААР, алгоритм (9) практически инвариантен как к ошибкам вычислений, так и к различного рода реализационным погрешностям.For example, in relation to a three-element equidistant AAR, consisting of isotropic non-interacting antenna elements, the value of the projector P, formed according to (11), (12), takes the form

Due to the fact that the action of the operators F _1j consists in the permutation and complex conjugations of the components of the vector

but actually

is determined using the AAR output signal, algorithm (9) is practically invariant both to computational errors and to various kinds of implementation errors.

При появлении полезного сигнала на входе ААР на управляющие входы адаптивных контуров 4 и блока максимизации мощности сигнала 5 поступает управляющий сигнал "Есть полезный сигнал". По этой команде коммутатор 5.1 блока максимизации мощности сигнала 5 подключает первые входы блока к адаптивным контурам 4, а коммутаторы 4.4 адаптивных контуров 4 переводят их в режим максимизации выходной мощности устройства. При этом блок максимизации мощности сигнала 5 в соответствии с выражениями (11), (12), (14) обеспечивает формирование проектора P' и выполнение операции перемножения проектора P' и вектора

обеспечивая совместно с адаптивными контурами 4 выполнение алгоритма (15), причем на выход коммутаторов 4.4 блоков адаптивных контуров 4 коммутируются вторые входы.The VVK obtained as a result of the solution of the recurrence algorithm (9) is a CB CM R _psh providing the maximum gain of the useful signal with complete suppression of interference. Therefore, at small angular distances between the signal sources and the interference, along with the interference, the useful signal will also be suppressed. In order to eliminate this effect, the algorithm (9) is regularized and a projector is used instead of the projector P
P ′ = P + γI (14) γ is the real coefficient), and algorithm (9) takes the form:

When a useful signal appears at the AAP input, the control signal "There is a useful signal" is received at the control inputs of the adaptive circuits 4 and the power-maximizing unit of signal 5. By this command, the switch 5.1 of the signal power maximizing unit 5 connects the first inputs of the block to adaptive circuits 4, and the switches 4.4 of adaptive circuits 4 put them into the mode of maximizing the output power of the device. In this case, the signal power maximizing unit 5 in accordance with the expressions (11), (12), (14) ensures the formation of the projector P 'and the operation of multiplying the projector P' and the vector

providing, together with adaptive circuits 4, the execution of algorithm (15), and the second inputs are switched to the output of the switches 4.4 of the adaptive circuit blocks 4.

 The composition and structure of the signal power maximizing unit 5 depend on the number of antenna elements of the AAP N. The signal power maximizing unit 5 includes a switch 5.1, N first dividers 5.2, N storage devices 5.3, a first adder 5.4, N-1 complex pairing unit 5.5, N -1 of the first multipliers 5.6, N-2 of the second dividers 5.7, N-2 of the second adders 5.8, the control parameter generation block 5.9, N * N of the second multipliers 5.10 and N of the output adders 5.11, the first outputs of the adaptive circuit blocks 4 through the 5.1 switch, which controls whose input is subconnected is connected to the first inputs of the first dividers 5.2, the second inputs of which are connected to the first output of the switch 5.1, and the outputs are connected to the inputs of the storage devices 5.3, the output of the first storage device connected to the first input of the first adder 5.4, and the outputs of the remaining storage devices connected to the inputs of the blocks of complex conjugation 5.5, with the first inputs of the first multipliers 5.6 and with the first inputs of the corresponding second multipliers 5.10, the outputs of the blocks of complex conjugation 5.5 are connected to the first the inputs of the corresponding second multipliers 5.10 and the second inputs of the first multipliers 5.6, the outputs of which are connected in pairs to the first and second inputs of the corresponding second dividers 5.7, the outputs of which are connected to the first inputs of the second adders 5.8, and the second inputs of the first 5.4 and second 5.8 adders are connected to the output of the block the formation of regulation parameters 5.9, and the outputs of the first adder 5.4 and second adders 5.8 are connected to the first inputs of the corresponding second multipliers 5.10, the second inputs of which are connected to the corresponding second the outputs of the blocks of adaptive circuits 4, and the outputs are connected to the inputs of the corresponding output adders 5.11, the outputs of which are connected to the third inputs of the corresponding adaptive circuits 4.

(11).The use of storage devices 5.3 provides storage of VVK

(eleven).

A detailed comparison of the characteristics of the prototype AAP algorithms and the claimed AAP was carried out using the simulation method. When modeling, we used a 3-element AAR, consisting of isotropic non-interacting antenna elements spaced in space by d ₁₂ = d ₂₃ = m _o / 2 (m _o signal wavelength), and the following assumptions about the signal-noise situation:
number of signals 1, interference 1;
the carrier frequencies of the signal and interference are identical;
ratio of signal powers, noise and dispersion of thermal noise: 10lg (p _c / σ $\genfrac{}{}{0ex}{}{\text{2}}{\text{w}}$ ) = 10 dB, 10 lg (P _p / σ $\genfrac{}{}{0ex}{}{\text{2}}{\text{w}}$ ) = 16 dB;
the angle between the normal to the line of placement of the antenna elements and the direction of arrival of the signal θ _c = 0 ^o .

The calculation results of the dependence of the signal / (interference + noise) ratio on the angle between the normal to the line of placement of the antenna elements and the direction of arrival of the interference (θ _p ) are presented in Fig. 12. In this case, the curve indicated by the number 1 is constructed, respectively, for the prototype AAR, and curve 2 for the claimed AAR with γ = γ _opt = σ $\genfrac{}{}{0ex}{}{\text{2}}{\text{w}}$ / N (N = 3). (Simulation was performed with respect to signals that have a pause during transmission).

 The graphs show that the noise immunity (signal / (interference + noise) ratio at the output) of receiving signals that have a pause during transmission (for example, signals with pseudo-random tuning of the operating frequency (MFC) proposed by the AAR is higher than the AAR of the prototype, in addition , in the claimed AAR there is no effect of unintentional suppression of the useful signal and provides increased noise immunity with respect to interfering signals regardless of their frequency band and power in any signal-noise situation. AR will enhance the noise immunity of radar systems, navigation and radio operating in complex interference-signal environment, in particular in a radio communication system with mobile objects, and, ultimately, will facilitate the introduction of AAP in these systems.

Claims (2)

 1. Adaptive antenna array containing N antenna elements connected via complex weight multipliers with corresponding inputs of the common adder, N adaptive circuits with control inputs, the first inputs of which are connected to the outputs of the corresponding antenna elements, the second inputs are connected to the output of the common adder, and the first outputs connected to the corresponding control inputs of complex weight multipliers, characterized in that an output power maximization unit is additionally introduced, the first and second inputs of which th connected respectively to the outputs of the first and second adaptive circuits, the outputs are connected to respective third inputs of adaptive circuits, and its control input connected to the control inputs of the adaptive circuit block.  2. The lattice according to claim 1, characterized in that the output power maximization unit consists of a switch, N first dividers, N storage devices, a first adder, N 1 complex conjugation blocks, N 1 first multipliers, N 2 second dividers, N 2 second adders, regularization parameter formation unit, N x N second multipliers and N output adders, the outputs of the switches are connected to the first inputs of the corresponding first dividers, the second inputs of which are connected to the first output of the switch, the control input of which is connected to the control the inputs of the storage devices, the inputs of which are connected to the outputs of the corresponding first dividers, the output of the first storage device connected to the first input of the first adder, and the outputs of the remaining storage devices connected to the inputs of the complex conjugation blocks, with the first inputs of the first multipliers and with the first inputs of the corresponding second multipliers , the outputs of the blocks of complex conjugation are connected to the first inputs of the corresponding second multipliers and to the second inputs of the first multipliers, the outputs of which are coupled to the first and second inputs of the respective second dividers, the outputs of which are connected to the first inputs of the second adders, the second inputs of the first and second adders connected to the output of the regularization parameter formation unit, and the outputs of the first adder and second adders connected to the first inputs of the corresponding second multipliers, the outputs of which are connected to the inputs of the corresponding output adders, and the inputs of the switch, the second inputs of the second multipliers and the control input of the switch are respectively Accordingly, the first, second and control inputs, and the outputs of the output adders with the outputs of the signal power maximizing unit.

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