SU943619A1 - Device for forming noise automatic compensator weight coefficients - Google Patents

Description

The invention relates to radio engineering and can be used in signal processing systems of multichannel sensors against the background of continuous correlated interference coming from directions other than the direction of arrival of useful signals, or having spectra different from the spectrum of the useful signal. A device for generating weight coefficients of noise cancellers, comprising a sequentially switched on phase shifter and a first multiplier, a series connected first and second integrators and a series connected reference signal generator, a subtractor, a first amplifier and a second multiplier, the second input of which is connected to the input of the phase shifter, while the output of the first integrator is connected to the second input of the subtractor 1J. However, the known device has a large time to establish weights, which results in a decrease in the degree of suppression of powerful transient interference. The purpose of the invention is to reduce the time for setting weights. The goal is achieved by the fact that the device for generating weights of the noise compensating autocompensators, comprising a series-connected phase shifter and a first multiplier, a series-connected first and second integrators and a series-connected reference signal generator, a subtraction unit, a first amplifier and a second multiplier, the second input of which is connected to the input a phase shifter, with the output of the first rator connected to the second input of the subtraction unit, sequentially connected second forces are introduced tel.

a linear detector, a differentiating unit, a threshold unit, a control unit and a switch, the second and third inputs and output of which are connected respectively to the output of the first multiplier, to the output of the second amplifier and to the input of the first integrator, while the output of the second integrator is connected to the input of the second amplifier.

The drawing shows a structural electrical circuit of the proposed device.

The device for generating the weights of the noise compensators includes a reference signal generator 1, a phase shifter 2, a first multiplier 3, the first and second integrators and 5, a subtraction unit 6, the first amplifier 7, the second multiplier 8, switch E, the second amplifier 10, a linear detector 11, a differentiation unit 12 threshold block 13 and control block 1.

The device for forming the weights of the noise compensators works as follows.

The input voltage of the phase shifter 2 is affected by the input voltage of the corresponding channel of the noise compensator (not shown), which is an additive mixture of components of a short duration signal, internal receiving noise and components of continuous interfering signals whose voltages are correlated between the compensator channels. At the output of the phase shifter 2, the phase of the output voltage is reversed, i.e. a conjugate input voltage is formed, which is multiplied by the output voltage of the auto-compensator in the first multiplier 3.

The initial state (at the beginning of the device weight setup) is the switch

9 closes the output of the first multiplier 3 with the input of the first integrator k, leaving the output of the second amplifier

10 disabled In this mode, the voltage proportional to the instantaneous value of the covariance coefficient of the voltage of the input autocompensator channel with the output voltage of the autocompensator output channel is smoothed in the integrator C, which has a time constant much smaller than that of the known device, and the smoothed value of this covariance coefficient goes to the second input of the subtractor 6, where this voltage is subtracted - from the voltage of the reference signal produced in the generator 1 of the reference

signal and having the amplitude of the components of the useful signal of the channel autocompensator and the phase opposite to the phase of the corresponding component. The resulting difference is amplified in the first amplifier 7 and the weighting factor formed at the output of this amplifier is multiplied by the input voltage of this auto-compensator channel in the second

$ multiplier 8. The signal from the output of the second multiplier enters the auto-compensator (not shown) for further processing. At the same time, the voltage is proportional to the smoothed value

stress covariance coefficient

input channel autocompensator and

its output channel goes to

input of the second integrator 5 where

integrated with more time constant. At the output of the second integrator 5, a voltage is generated proportional to the increment of the specified smoothed covariance coefficient,

. which is then amplified in the second amplifier 10 and whose module, formed in the linear detector 11, is differentiated in the differentiating unit, Free action of powerful interference is the amount of weight produced by the circuit consisting of the phase rotator 2, the first multiplier 3 of the first integrator, subtractor 6, the generator 1 of the reference signal C of the first amplifier 7i is stabilized and oscillating around a slowly varying value over a short period of time. At the output of the second integrator 5, this slowly varying value is proportional to the increment of the specified smoothed covariance coefficient, and then amplified in the second amplifier 10. As soon as the increment of the smoothed covariance coefficient at the output of the second amplifier 10 becomes approximately constant, the threshold unit 13 is triggered and control block l connected to the output of the threshold block

Claims (1)

 13 turns off (for a time interval not exceeding the time constant of the second integrator 5) the output of the first multiplier 3 from the input of the first integrator k and connects the output of the second amplifier 10 to the input of the first integrator 10. That is, not the instantaneous value of the covariance coefficient is fed to the input of the first integrator, k, but proportional to the smoothed increment of this covariance coefficient; the corresponding auto-compensator channel with auto-compensator output voltage. After the specified time interval has expired, the control unit disconnects the output of the second amplifier 10 from the input of the first integrator k and disconnects the output of the second amplifier 10 from the input of the first integrator k and connects the output of the first multiplier 3, i.e. the device returns to its original state to determine the new covariance coefficient and determine the new increment value of this coefficient. As the value of the weight coefficient of the device approaches the value that achieves the maximum interference suppression coefficient in the autocomputer, the covariance coefficient and its increment tend to zero, which leads to stabilization of the weight factor formed in the device. A comparative analysis of the known and proposed devices shows that the time for setting the weighting factor in the proposed device is significantly reduced and this reduction, depending on the interference power, reaches 10 dB. The invention The device for generating the weight coefficients of the noise compensators, comprising a series-connected phase shifter and a first multiplier, a series-connected first and second integrators and a series-connected reference signal generator, a subtractor, a first amplifier, and a second multiplier, the second input of which is connected to the phase shifter input, while the output the first integrator is connected to the second input of the subtraction unit, characterized in that, in order to reduce the establishment time The second amplifier, a linear detector, a differentiating unit, a threshold unit, a control unit and a switch, the second and third inputs and the output of which are connected respectively to the output of the first multiplier, to the output of the second amplifier and to the input of the first integrator, and the output of the second the integrator is connected to the input of the second amplifier. Sources of information taken into account in the examination 1. Brennon L.E., Pugh E.L. und Reed I.S. Control-Loop Noise in Adaptive Array Antennas. - IEEE Trans, on AES, ff 2, 1971, p. 260, Fig. 2 (prototype). with StfXOh ofmokatmsato l