SU1307600A1 - Device for reception of data signals - Google Patents

Abstract

The invention relates to telecommunications. The purpose of the invention is to increase the reliability of reception. The device contains a demodulator 1, a code converter 2, a decoder 3, a control key 4. The signal-to-noise ratio meter (SNR) 5, the comparison block 6, the element OR 7 are newly entered. The SNR measurement result is in the form of a signal of a certain level block 6, where it is compared with a threshold signal based on data reliability requirements. If the SNR exceeds the threshold signal, then the output of block 6 will be the signal O. Otherwise there will be a signal 1. 1 Il. (L с - with о -vl 05 о о

Description

The invention relates to telecommunications and can be used in data transmission and telegraphy systems.

The purpose of the invention is to increase the reliability of receiving data signals.

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

Device for receiving signals

data contains demodulator 1, which transforms the useful signal to the power of noise on

a code 2 equalizer, a decoder 3, a control key 4, a signal-to-noise meter 5, a comparison block 6 and an OR element 7.

The device works as follows.

The modulated harmonic signal with noise enters demodulator 1, where it is converted into a video signal (5

Duration of the processed code combination.

The result of measuring the ratio of signal / noise in the form of a signal of a certain level goes to block 6 of the comparison where it is compared with a threshold signal, we establish 1m based on the requirements to the reliability of the data. If the signal-to-noise ratio exceeds pore

cash, the instantaneous values of which are a gob signal, then at the output of block 6

vary randomly from minus infinity to plus infinity depending on the transmitted signals and the received interference implementations. The code converter 2 converts the video signal into a sequence of pulses representing the elements of the transmitted code combinations, for example, in the form of combinations 1 and O. In the decoder 3, checks are made for the selected code of logical connections between the elements of the code combinations. Based on the results of the checks, a decision is made on the presence or absence of errors in the processed code combination. If an error is detected, then the signal 1 appears at the control output of the decoder 3, otherwise the signal O. The information part of the code combination is sent to the information input of the control key 4. If the control input of the key 4 at this moment has the signal O then the received information is output to the information output. If signal 1 is present at the control input of the control key 4, then it is open, the received information is reset and does not pass to the information output.

In the case of fading of useful signals and increasing noise levels at the output of decoder 3, the likelihood of undetectable errors increases, which cannot be found fundamentally with the help of codes. To eliminate this drawback, the proposed device implements a second processing branch consisting of meter 5

signal-to-noise ratio, comparator block 6, and element 7. The signal / noise ratio meter input signal is supplied from the outputs of demodulator 1 as a random process, the average value of which changes according to the law of the transmitted telegraph signal. The signal-to-noise ratio meter 5 estimates the magnitude of the power ratio

Duration of the processed code combination.

The result of measuring the signal-to-noise ratio in the form of a signal of a certain level is fed to comparison unit 6, where it is compared with a threshold signal, we establish 1m based on data reliability requirements. If the signal-to-noise ratio exceeds the threshold signal, then the output of block 6

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the signal O appears, otherwise signal 1. Thus, the stability of the reliability of the data output to the receiver is ensured from below, and the accuracy of error detection is improved. When signal 1 appears at the control second output of decoder 3, the signal from comparison unit 6 is output to the control output of the device in order to request re-issuance of messages over the feedback channels.

Claims (1)

Invention Formula A device for receiving data signals comprising a demodulator, the output of which is connected to the input of a code converter, the output of which is connected to the input of a decoder, the first output of which is connected to the information input of the controlled key, and the input of the demodulator is a signal input of the device, information and The control outputs of which are, respectively, the output of the controlled key and the control input of the controlled key, characterized in that, in order to increase the reliability of reception, the element OR block is entered into it comparing and measuring the signal-to-noise ratio, the output of which is connected to the signal input of the comparison unit, the output of which is connected to the first input of the OR element, the second input of which is connected to the second output of the decoder, and the output of the demodulator is connected to the input of the measuring signal-to-noise ratio, output 313076004 the OR element is connected to the control input of the comparison unit is the threshold input of the control key, and the threshold output of the device.