SU794743A1 - Device for quality control of communication channels - Google Patents

Description

one

The invention relates to control devices of wired communication systems, can be used to analyze the state of telegraph and telephone communication channels, subject to intense interference, leading to the appearance of group errors.

A device for controlling the quality of communication channels is known, which contains a reversible counter, on whose counting input is given an error signal, and the subtraction input is connected to the output of the OR element, one of the inputs of which is connected to the output of a divider with a variable division factor, to the input of which an input signal is supplied , the other inputs of the OR element are connected to the outputs of multiplication blocks 1.

However, the known device has a low accuracy of quality control of communication channels, characterized by grouping errors. This is due to the fact that in the known device the independent nature of the errors is assumed and the nature of their grouping is not analyzed at all.

The aim of the invention is to improve the accuracy of quality control of communication channels characterized by grouping errors.

For this purpose, the device for controlling the quality of communication channels, containing a reversible counter, to the counting input of which an error signal is applied, and the subtraction input is connected to the output of the OR element, one of the inputs of which is connected to the output of a divider with a variable division factor, to the input of which is fed the input signal, the other inputs of the OR element are connected to the outputs of the multiplication units, the NOT element, the first and second AND elements are entered,

; b-trigger, first and second counters, a registration unit and a decoder, while the counting input of the reversible counter is combined with the S input of the Trigger and the input of the element NOT, the input of the divider with a variable division factor is combined with one of the inputs of the elements And, the output the element is NOT connected to another input of the first element I, the output of which is connected to the ./-input of the 5 flip-flop, the direct output of which is connected to the counting input of the first counter, and the inverse output to another input of the second element I, whose output is connected to the counting input second sche snip or zero inputs of the first state and

the second counters are combined with the polling input of the registration unit and the decoder and are connected to an additional divider output with a variable division factor; the outputs of the first and second counters

Claims (1)

connected via serial connections .., ... valuable registration unit and descrambler to the inputs of the corresponding multiplication units. The drawing shows a structural electrical circuit of the proposed device. The device for controlling the quality of communication channels contains a reversible counter 1, the element OR 2, a divider 3 with a variable division factor, multiplication blocks 4, a element NOT 5, the first element AND 6, / 5 trigger 7, the second element And 8, the first 9 and the second 10 counters, the registration unit 11 and the decoder 12. The device operates as follows. The input realization of errors and correctly received elements of the message in the form of a random sequence of units (corresponding to distorted elements of the message) and zeros (corresponding to correctly received elements of the message) are fed to the counting input of counter 1 and S-input / 5-trigger 7. This is a series of units in the sequence, there is an error packet, and a series of zeros between packets — an interval. The reversible counter performs a sequential analysis of the incoming signals. If after some time the difference between the number of pulses arriving at the counting input of counter 1 and the subtracting input from the output of the OR 2 element exceeds a certain set number A, then the output of counter 1 will show a signal indicating unsuitable for the given communication channel. The number A in counter 1 is set during the design process, based on the specified reliability of the estimation of the state of the communication channel, and the constant threshold level component is determined by the frequency of the signals from the output of the divider 3 with a non-temporary dividing factor, to the input of which pulses are received from the synchronous receive distributor (not shown). The signal unit ("error), which defines the beginning of the error packet and arrives at the 5-BCS of the trigger 7, sets the latter into the one state. On the leading edge of the signal taken from the direct output of the trigger 7, counter 9 is triggered, as a result of which the latter calculates the number of error packet groups (corresponding to the number of gaps L) in the input error realization. In the event that a packet ends, but the arrival of the first zero (corresponding to the correctly received message element, the first element of the safety-free night), at the output of the element HE 5, a unit level signal is applied to the first input of the element 6. As a result, the signal from the synchronous receive distributor transmitted through the open element I 6 to the I input of the trigger 7 sets the latter to the zero state. The signal from the inverted output of the trigger 7 permits the passage of pulses of the clock frequency through the AND 8 element to the counting input of the counter 10, which counts the number of pulses proportional to the duration of the current and interval of error-free reception. On the leading edge of the signals arriving with the period TI from the additional output of the divider 3 to the input of the onros of block 11, the latter estimates the average duration L of a slip-free reception as where LS is the first reading of the first counter (9); L - shows the second counter (10). On the falling edge of the pulse coming from the auxiliary output of the divider 3 to the input of the onros of the decoder 12 of medium duration for error-free reception and the input for setting the zero state of the counters 9 and 10, the decoder 12, whose inputs are connected to the outputs of the block 11, produces, depending on the value of L one of its outputs is a signal arriving at the input of the corresponding block 4, and the counters 9 and 10 are set to the zero state, preparing the device for a new measurement cycle. The duration of the time intervals Ti is chosen from the condition 1 -I PSS where GVSP is the average duration of the burst of errors. The multiplication blocks, made on the basis of shift registers, convert the pulse appearing at the input of one of them into a series of pulses. The number of pulses in a series is determined by the coefficient of the corresponding multiplication unit. The pulses from the output of the corresponding block 4, which determine the variable component of the threshold level, through the element OR 2 are fed to the input of the read out of counter 1, thereby changing the steepness of the device’s operating characteristics depending on L and preferring the channels with a larger value of L. The variable component of the threshold the level at the output of blocks 4 introduces an amendment proportional to the average duration of an error-free reception — L. The longer the average interval of an error-free reception, the more tightly the errors are grouped and the greater the effect vnost correcting them. The values of the multiplication factor of blocks 4 are assigned depending on the statistical characteristics, the transmitted messages and the used communication channels. Thus, the proposed device makes it possible to increase the accuracy of assessing the quality of monitored communication channels by taking into account the degree of error grouping in real communication channels by the average duration of error-free reception intervals. It provides the ability to select channels with a greater degree of grouping, which is more preferable when transmitting messages (in particular, when transmitting messages through decameter channels). The latter, in turn, leads to a dry increase in the reliability and speed of information transfer in communication systems. The invention The device for controlling the quality of communication channels, contains its reversible counter, to the counting input of which an error signal is applied, and the subtraction input is connected to the output of the OR element, one of the inputs of which is connected to the output divider with a variable division factor, to the input an input signal is given, the other inputs of the OR element are connected to the outputs of multiplication units, characterized in that, in order to improve the accuracy of quality control of communication channels, characterized by error grouping, the element NOT is entered, first th and second elements And, 5-flip-flop, first and second counters, registration unit and decoder, while the counting input of the reversible counter is combined with the 5-input of the 5-flip-flop and the input of the element NOT, the input of the divider with a variable division factor is combined with one of the inputs And elements, the output of the element is NOT connected to another input of the first element AND, the output of which is connected to the -input / 5-flip-flop, the direct output of which is connected to the counting input of the first counter, and the inverse output to another input of the second And element, the output of which is connected to countable The second input of the second counter, the zero state inputs of the first and second counters are combined with the polling input of the registration unit and the decoder and connected to the additional output of the divider with a variable division factor; the outputs of the first and second counters are connected through the serially connected registration unit and the decoder to the inputs of the corresponding multiplication units . Sources of information taken into account during the examination 1. USSR Author's Certificate No. 370735, cl. H 04B 3/46, published. 1970.