RU2208880C2 - Device for generating directivity pattern zero of phased antenna array in noise direction - Google Patents

Abstract

FIELD: instrumentation engineering; noise suppression devices. SUBSTANCE: device that functions to generate directivity pattern zero in antenna arrays wherein part of antennas failed in the course of service to compensate for mutual impact of antennas, impact of structural components, and array manufacturing defects by using information about useful signal amplitude and in some cases to compensate for pattern-generating circuit error has antennas, pattern-generating circuit, and weighting coefficient computer. Signals picked off antenna output are conveyed to pattern-generating circuit; the latter conducts weighted addition of signals arriving from antenna outputs, weighted coefficient computer finds weighted coefficients of pattern-generating circuit; amplitudes and phases of signals arriving from outputs of antennas are entered in weighted coefficient computer; as distinct from prior art, amplitudes and phases of signal across pattern-generating circuit and amplitudes of useful signal are entered in addition in weighted-coefficient computer. EFFECT: enlarged functional capabilities. 7 cl, 2 dwg

Description

 The invention relates to instrumentation and can be used to suppress interference by forming a zero radiation pattern (LH) of a phased array antenna (PAR) in the direction of interference.

 Known devices for suppressing interference using the HEADLIGHT, for example, described in [1], containing antenna elements (AE), diagram-forming circuits (DOS), weighting coefficient calculators (IAC) DOS. In these devices, the angular coordinates of the interference and the useful signal are introduced into the VVK, and the DOS forms the DN with zeros in the direction of interference.

 The disadvantage of these devices is the need to know the angular coordinates of interference and a useful signal.

It is also known the device described in [1], the functional diagram of which is shown in Fig. 1, adopted as a prototype, containing AE 1, DOS 2, VVK 3. In this device, DOS carries out weighted summation of signals from the outputs of AE, VVK calculates the weight coefficients of DOS w ₁ ... w _N , at which the DOS generates a pattern with zeros in the direction of interference, for which the amplitude and phase of the signals at the AE outputs x ₁ (t) ... x _N (t) are introduced into the HVC.

 The disadvantage of the prototype is the impossibility of forming zeros in the headlights in which part of the AE failed during operation, due to the need to explicitly set the characteristics of the AE to calculate the weight coefficients.

 The purpose of the invention is the provision of the possibility of forming zeros in the headlights of the headlamp, in which part of the AE is out of order during operation.

 In the prototype for the formation of DN in DOS, it is necessary to know the coordinates of the AE and their transfer functions. If these values change during operation, it will be impossible to generate the required diagram. In the proposed device, the characteristics of AE are not set, but are calculated in the process of forming weight coefficients. For this, information about the amplitude of the useful signal is used. The amplitude of the useful signal is compared with the amplitude of the signal at the output of the DOS, taking into account the amplitude and phase of the signal at the outputs of the AE and the phase of the signal at the output of the DOS, for which the values of the amplitude and phase of the signal at the output of the DOS and the amplitude of the useful signal are additionally entered, and based on the results comparisons weighting factors are formed.

 The proposed device, like the prototype, contains AE, DOS, VVK, the signals from the AE outputs are fed to the DOS, the DOS carries out a weighted summation of the signals from the AE outputs, the VVK calculates the weight coefficients of the DOS, for which the values of the amplitudes and phases of the signals from the AE outputs are entered into the VVK , and, unlike the prototype, in BB, the amplitude and phase of the signal at the output of the DOS and the amplitude of the useful signal are additionally introduced.

 In particular cases of device execution, each AE can have its own transfer coefficient, its own radiation pattern, AEs can pre-amplify and convert the signal frequency, the amplitude of the useful signal can vary according to the law of pulse-width or frequency-pulse modulation, the amplitude and phase of the signal at the output DOS, the amplitudes of the useful signal, before entering the weighting factors in the calculator, can be determined programmatically.

 In addition to the main technical result, the proposed device provides compensation for the mutual influence of AE, the influence of structural elements and technological errors in the manufacture of HEADLIGHTS. In the case of non-software determination of the values of the amplitude and phase of the signal at the output of the DOS, the device allows you to compensate for the errors of the DOS.

 Figure 1 shows the functional diagram of the prototype. Figure 2 shows a functional diagram of the invention.

The device shown in figure 2, contains AE 1, DOS 2, VVK 3, the signals from the outputs of AE x ₁ (t) ... x _N (t) are supplied to the DOS, VVK calculates the weight coefficients of the DOS w ₁ ... w _N , the values of the amplitudes and phases of the signals from the outputs of the AE x ₁ (t) ... x _N (t), the signal at the output of the DOS Y '(t) and the amplitude of the useful signal | Y (t) | are introduced into the VVK.

где Y'(t) - сигнал на выходе ДОС в момент времени t,
N - количество АЭ;
w_i - i-й весовой коэффициент;
x_i(t) - сигнал на выходе i-го АЭ в момент времени t.The device operates as follows. In VVK, the weighting coefficients w ₁ ... w _{N are} assigned initial values. Signals x ₁ (t). ..x _N (t) from the outputs of the AEs enter the DOS, in which, by their weighted summation, the beam pattern is formed and the output signal Y '(t)

where Y '(t) is the signal at the output of the DOS at time t,
N is the amount of AE;
w _i is the i-th weight coefficient;
x _i (t) is the signal at the output of the i-th AE at time t.

где ΔRеw_i - приращение действительной части i-го весового коэффициента;
ΔImw_i - приращение мнимой части i-го весового коэффициента;
k₁, k₂ - постоянные коэффициенты;
T - период, в течение которого измерялись параметры сигналов;
|Y(t)| - амплитуда полезного сигнала в момент времени t;
|Y′(t)| - амплитуда сигнала на выходе ДОС в момент времени t;
x_i(t) - сигнал на выходе i-го АЭ в момент времени t;
Y'(t) - сигнал на выходе ДОС в момент времени t.Into the VVK, x ₁ (t) ... x _N (t), Y '(t), | Y (t) | are introduced. Then w ₁ -w _N get increments that can be calculated, for example, by the formulas

where ΔRеw _i is the increment of the real part of the i-th weight coefficient;
ΔImw _i is the increment of the imaginary part of the i-th weight coefficient;
k ₁ , k ₂ - constant coefficients;
T is the period during which the signal parameters were measured;
| Y (t) | - the amplitude of the useful signal at time t;
| Y ′ (t) | - the amplitude of the signal at the output of the DOS at time t;
x _i (t) is the signal at the output of the i-th AE at time t;
Y '(t) is the signal at the output of the DOS at time t.

 The real and imaginary parts of the signals can be determined through their amplitudes and phases according to Euler's formulas.

X ₁ (t) ... x _N (t), Y '(t), | Y (t) | and ΔRew _i and ΔImw _i are calculated.

If Y '(t) or | Y (t) | before entering into the IHC are not measured, but calculated programmatically, Y '(t) according to the above formula, a | Y (t) | according to the formula for the amplitude of the useful signal, the values x ₁ (t) ... x _N (t) are introduced into the VVK at those times that were used in the calculations Y '(t) or | Y (t) |. When calculating Y '(t), the values x ₁ (t) ... x _N (t) from the previous iteration can be applied.

 The procedure is repeated until the formation of DOS DN with zeros in the direction of interference. This is achievable because the described procedure is a kind of gradient synthesis of MDs, as described, for example, in [2]. In this case, not a virtual training set, but real-life signals are used to synthesize MDs, which allows us to synthesize MDs adapted to the real existing characteristics of the elements and the interference environment.

 AEs, DOSs that carry out weighted summation of signals from AEs are well known [2].

LITERATURE
1. Dragalin V.V., Kazakov V.D., Kanaschenkov A.I., Merkulov V.I., Samarin O.F., Chernov M.V. Methods and algorithms for noise protection of airborne radar systems from multipoint interference. - Foreign electronics. Successes of modern radio electronics, 2001, 2, p. 1-52.

 2. Voskresensky D.I., Kremenetsky S.D., Grinev A.Yu., Kotov Yu.V. Computer aided design of antennas and microwave devices. - M.: Radio and Communications, 1988.

Claims (7)

1. A device for generating a zero radiation pattern of a phased antenna array in the direction of interference, containing antenna elements, a beamforming circuit, a weighting calculator, in which the signals from the outputs of the antenna elements are fed to a beamforming circuit, the beamforming circuit performs a weighted summation of the signals from the outputs of the antenna elements, weight calculator coefficients calculates the weighting coefficients of the beam-forming circuit, the values of the amplitudes and phases of the signals from the outputs of the antenna elements are introduced into the weight calculator, characterized in that the signal at the output of the diagram-forming circuit and the value of the amplitude of the useful signal are additionally introduced into the weight calculator, and the weight coefficients are adjusted according to the formulas

where ΔRew _i is the increment of the real part of the i-th weight coefficient;
ΔImw _i is the increment of the imaginary part of the i-th weight coefficient;
k ₁ , k ₂ - constant coefficients;
T is the period during which the signal parameters were measured;
| Y (t) | - the amplitude of the useful signal at time t;
| Y ′ (t) | - the amplitude of the signal at the output of the DOS at time t;
Xi (t) is the signal at the output of the i-th AE at time t;
Y '(t) is the signal at the output of the DOS at time t.  2. The device for forming a zero radiation pattern according to claim 1, characterized in that each antenna element has its own transmission coefficient.  3. The device for forming a zero radiation pattern according to claim 1, characterized in that the antenna elements carry out preliminary signal amplification.  4. The device for forming a zero radiation pattern according to claim 1, characterized in that the antenna elements convert the frequency of the signal.  5. The device for forming a zero radiation pattern according to claim 1, characterized in that each antenna element has its own radiation pattern.  6. The device for generating a zero radiation pattern according to claim 1, characterized in that the amplitude of the useful signal varies according to the law of pulse width modulation.  7. The device for generating a zero radiation pattern according to claim 1, characterized in that the amplitude of the useful signal changes according to the law of frequency-pulse modulation.

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