SU1352659A1 - Device for adaptive correction of signal - Google Patents

Abstract

The invention relates to telecommunications and provides improved quality correction with a relatively high level of noise. The device contains a corrector I, 2N + 1 blocks of subtraction 2, shaper 3 of the intercorrelation signal, delay lines (LZ) 6, 8, transducer 7 of the spectrum, multi-split LZ 9.10, consisting of 2N + 1 delay elements, 2N + 1 shapers 11, consisting of 2N + i multipliers 12 and adder 13, and 2N + 1 additional formers 14 of the intercorrelation signal. Shaper 3 consists of 2N + 1 circuits consisting of multiplier 4 and integrator 5. Spectrum converter 7 inverts the spectrum of the corrected signal. Samples of the corrected signal are stored in multi-split LZ 10, and samples of the uncorrected signal are stored in multi-split LZ 9. Multipliers 4 form signals of correlation between the stored samples of the corrected signals with the inverted spectrum and the stored samples of the corrected signals with the non-inverted spectrum with the LZ 8. . The formers 11 are based on error signals and inter-correlation signals between unadjusted sig-. signals and corrected signals with an inverted spectrum, formed by additional formulas, with S OO

Description

by the rollers 14, form the control signals for the offset. 1. As a result, the device is adaptive. The invention relates to telecommunications and can be used to correct signals.

The purpose of the invention is to improve the quality of correction at a relatively high level of noise.

The drawing shows an electrical block diagram of an adaptive signal correction device.

The adaptive signal correction device contains a 1, 2N + 1 equalizer of 2-l-2- (2N + l) subtraction blocks, a formator 3 of the intercorrelation signal, consisting of 2N-H circuits, each of which contains a multiplier 4 ((2N + l )) and integrator 5 (5-1- -5- (2N + l)), first delay line 6, spectrum converter 7, second delay line 8, first multi-drop delay line 9 consisting of delay elements 9-1-9 - (2N + I), the second multi-branch delay line 10 consisting of delay elements 10-1-.-10- (2Ы + 1), 2N + 1 drivers 11-1- -11- (2N + 1) of the correction signal, consisting of multipliers 12-1-12- (2N + I) and an adder 13, 2N + 1 of additional (2N + I) formers of the wave-correlation signal.

Adaptive Correction Device

The signal works as follows.

The received samples of the input signal, Y (i) are fed to the input of equalizer 1 and, through the first delay line 6, to the input of the second multi-drop delay line 9. From the output of corrector 1, the corrected signal samples V (i) are fed to a spectrum converter 7, which inverts the spectrum of the corrected signal by multiplying the sequence of samples from the output of corrector V (i) by samples doubled

NOY complex with a negative sign of the carrier frequency argument tUj ,.

on correction of linear distortions of this so-called non-estimation of transmitted symbols. 1 il.

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The spectrum inversion algorithm can be written as follows:

V (i) V (i) exp (-j2u; oi4t),

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where V (i) is the signal samples at the output of the spectrum converter 7, following through the clock interval lt.

Sampling corrected signal with inverted spectrum

d

V (i) from the output of the spectrum converter 7 is fed to the input of the second multi-split delay line 10, where they are stored in the time interval -N, N. The first and second delay lines 9 and 10 are designed to equalize the time delay between samples of corrected and uncorrected signals. The uncorrected signal samples are stored in the time interval -N, N using the first multi-split delay line 9. Samplings of the corrected signal with invertirol

V (i. + N),. . .V (i-N) are fed to the corresponding multipliers 4-l-4- (2N + l) formers 3 and additional formers 14-1-14- (2N + 1). The second inputs of the multipliers 4-l-4- (2N + l) of the former 3 receive corrected signal samples with a non-inverted spectrum.

l .

V (i) delayed by the second line 8 by a delay time equal to half the length of the first multi-drop delay line 9. After averaging in integrators 5-l-5- (2N + l) shaper 3, the samples of the intercorrelation signal between the corrected signals and signals with an inverted spectrum are fed into the blocks 2-1 -2 -2 (2N + l), the second inputs of which are fed reference signals of a given level (2N + 1). Error signal

from each block 2-l7-2- (2N + l) the outputs go to shapers 11-1- -11- (2N + 1) to the inputs of the corresponding multipliers 12-1-12- (2N + l), to others the outputs of which provide intercorrelation signals between unadjusted signals and corrected signals with an inverted spectrum, formed in additional formers 14-1-14- (2N + 1) in each driver 11-1-11- (2N + 1) from the outputs of the multipliers 12 -1- -12- (2N + 1) signals are fed to the adder 13, from the output of which the generated control signals of the equalizer 1 are fed to its control input.

The process of adaptive adjustment of the gain factors of the corrector 1 regulators is described by the following expression:

c (i + i) c, (i) - / tA (,

Pr-n

where C (i + l), C (i) is the complex gain of the nth regulator of corrector 1 by (i + l) -OM and i-M adjustment step, respectively;

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samples of the signal of mutual correlation between the corrected signals and signals with an inverted spectrum in the time interval -N,

E1M

- reference signal samples

vasimocorrelation in the -N, N Y interval — samples of the uncorrected signal in the nth tap of the second multi-drop delay line 10;

BUT

Vj - counts of the corrected signal with an inverted spectrum in the 1st tap of the first multi-drop line 9 delay;

d - weight coefficient; - - sign of static averaging; - a sign of complex conjugation.

As a result, the device performs adaptive correction of linear signal distortion without producing estimates of the transmitted symbols. Therefore, there is no violation of the convergence of the correction process due to the inaccuracy of the estimates of the transmitted Symbols occurring in known devices. This allows for adaptive correction of the signal at any value of the Initial linear distortion, which

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leads to noise immunity.

Claims (1)

Invention Formula An adaptive signal correction device, containing a corrector, the signal input and output of which are the input and output of the adaptive signal correction device, and the intercorrelation signal generator, consisting of 2N + circuits, each of which contains serially connected multiplier, whose inputs are combined and are the first input of the intercorrelation signal generator, and the integrator, whose outputs are the outputs of the mutual correlation signal generator, characterized in that, in order to improve the quality of the correction and a relatively high noise level, a series-connected spectrum converter, the input of which is connected to the output of the equalizer, and a first multi-drop delay line consisting of 2N + 1 series-connected delay elements, connected in series the first delay line, the input of which is connected to the equalizer input, and a second multi-tap delay line consisting of 2N + I series-connected delay elements; a second delay line, whose input is connected to the output of the equalizer, and the output is connected to the first the input of the intercorrelation signal generator, 2N + 1 subtraction blocks, the first inputs of which are connected to the corresponding outputs of the intercorrelation signal generator, and the second inputs are the input signals of the specified level signals, 2N + 1 correction signal formers, consisting of 2N + 1 multipliers, the first and second inputs of which are respectively the first and second inputs of 2N + 1 correction signal formers and an adder, whose inputs are connected to the outputs of the 2N + I multipliers, and the output is the output of 2N + 1 signal conditioners in corrections, 2N + 1 additional formers of the intercorrelation signal, in this case 4; oN 2N + of the formers of the correction signal are connected to the control inputs of the corrector, the outputs of the delay elements of the first multi-dots water delay line connected to additional forms: signal operators second inputs of corresponding-intercorrelation multipliers, the first input of which signal conditioning circuits connected to the output of the corresponding intercorrelation, the outputs of the 2N + 1 delay delay cell element are connected to the first inputs - the first delay line, and the second inputs The 2N + 1 signal formers of the core are connected to the outputs of the overload elements, the second inputs of which are the connectors of the first multi-drop line are connected to the corresponding outputs 2N + 1 of the hold.