SU1504693A1 - Adaptive grid with limited directional pattern - Google Patents

Abstract

The invention relates to radio engineering. The purpose of the invention is to stabilize the gain in the direction of the expected arrival of the useful signal. In the antenna array, the input signals, received by the antenna elements 1, are sent to quadrature dividers 2, which carry out complex weighting of signals in each of the N channels using weighting multipliers of 3 inphase and quadrature chains. Thereafter, the weighted signals are summed in adder 7. The goal is achieved by imposing a weight constraint. These constraints are implemented by a control loop consisting of N-input adders 9, squaring blocks 10, a three-input adder 11, a constant voltage source 12, an integrating link 13, multipliers 14, and three-input channel adders 6. This maximizes the signal / ratio. noise at the output of adder 7 with restrictions in accordance with the gradient adaptation algorithm. 1 il.

Description

tn

ABOUT

four

Od

WITH

with

31

The invention relates to radio engineering and can be used in various radar systems having an antenna array as a receiving antenna system.

The purpose of the invention is to stabilize the gain in the direction of the expected arrival of the useful signal.

The drawing shows a structural scheme of an adaptive antenna array with limited directivity.

An adaptive antenna array with a limited directivity contains N channels, each of which consists of antenna element 1, adaptive weighing unit made in the form of quadrature divider 2, weight multipliers 3 in-phase and quadrature chains, multiplier 4, low-pass filters 5 and channel adders 6 , made three-code, adder 7, control unit 8, first and second N-input adders 9, squareing blocks 10, three-input adder 11, constant voltage source 12, integrating link 13 and multipliers 14.

Adaptive antenna array with limited directivity works as follows.

The input signals received by the antenna elements 1 are fed to quadrature dividers 2, which allow complex weighting of signals in each channel using weighting multipliers 3 in phase and quadrature

chains, after which the weighted signals are summed in adder 7.

It is known that the signal-to-noise ratio at the output of the adaptive antenna array does not change when the weight vector is multiplied (in this case, the weight factors are played by the weight multipliers 3) by an arbitrary factor. This degree of freedom can be used to maintain a predetermined gain of the antenna array in the direction of the expected arrival of the useful signal by imposing a restriction on the weighting factors.

to

W

AND

(X

1-1

with

city -1

) - (

with

one,

one

) eleven)

gdeso - oh; - weights

on the in-phase and quadrature outputs of quadrature dividers 2, respectively. The invention maximizes the signal-to-noise ratio at the output of adder 7 with constraints (1) in accordance with a gradient (correlation) adaptation algorithm. At the same time, a new control loop appears that implements the constraints (1) and includes N-input adders 9, squaring blocks 10, three-input adder 11, constant voltage source 12, integrating link 13, multipliers 14 and third inputs channel adders 6, made three-input, I

Claims (1)

Invention Formula five five five 0 0 five 0 five An adaptive antenna array with a limited directivity, containing a control unit., An adder, two squaring units, a first N-INPUT adder, N channels, each of which consists of a series-connected antenna element and an adaptive weighting unit. the divider, to the outputs of which are connected the weighting multipliers of the in-phase and quadrature chains, each of which contains a series-connected multiplier, a low-pass filter and a channel adder, the output of which connected to the second input of the corresponding weight multiplier, the outputs of both weight multipliers of each channel are connected to the inputs of the adder, the output of which is connected to the first inputs of the multipliers of the in-phase and quadrature chains of each channel, the outputs of the control unit are connected to the second inputs of the channel adders of each channel that differs that, in order to stabilize the gain in the direction of the expected arrival of the useful signal, a second N-input adder, sequentially connected source on the voltage, a three-input adder, an integrating link, the first multiplier, the output of the integrating link is connected to the first input of the entered second multiplier, the channel adders are filled with three input, third inputs of the In-phase and quadrature chains of which are connected to the output of the first and the output of the second multipliers, respectively, the inputs of the first and second N-input adders. connected to the outputs of the channel in-phase and quadrature chains of the adders, respectively, corresponding to 046936 The squaring block is connected to the second and third inputs of the three-input adder, respectively, the second inputs of the first and second multipliers are connected to the corresponding outputs of the first and second N-INPUT adders, and the output of the adder is the output IQ of an adaptive antenna array with limited directivity.