SU1405121A2 - Device for monitoring discrete communication channel - Google Patents

Abstract

The invention relates to telecommunications. The purpose of the invention is to reduce the control time and increase the reliability of the control. The device contains the keys 1 and 2, the normalizing counter (C) 3, the EL of 4 or 5, the reversing C 6, C 7 truncation of the analysis interval, the decoder 8, the comparators 9 and 10, and the shaping device 11 of the guard interval. To take into account the dependence of the values of the threshold levels on the sample size when analyzing the likelihood ratios, the basic ratio of the sequential analysis is used. This makes it possible to reject the direct calculation of the number of errors, m, and to operate on the functionally dependent on m value M, the definition of which is implemented in the device. The value of M is fixed at C 6, and the values of the lower A and upper R thresholds: the levels determine the comparison thresholds of the Comparators 9 and 10, the Goal is achieved by dynamically controlling the values of the threshold levels with an increase in the sample size using the entered decoder 8 and the Comparators 9 and 10. 3 il. i O)

Description

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Js

 About 01

YU

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sixteen

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eight

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eleven

The invention relates to telecommunications, can be used to determine the quality of channels intended for the transmission of discrete Signals, and is an enhancement of the invention according to the author. No. 1133677

The purpose of the invention is to reduce the monitoring time and increase the reliability of the control by dynamically controlling the values of the threshold levels with an increase in the sample size.

Fig. 1 shows a structural electrical circuit of a device for monitoring a discrete communication channel; figure 2 - timing charts of the device; on fig.Z - graphs of solving equations.

The device for controlling a discrete communication channel contains the first and second keys 1 and 2, the normalizing counter 3, the first and second elements OR 4 and 5, the reversible counter 6, the counter 7 of the truncation of the analysis interval, the decoder 8, the first and second comparators 9 and 10, a guard interval generator 11, a clock bus 12, an error pulse bus 13, a device initialization bus 14 in the initial state, a channel health indication bus 15 a channel fault indication bus 16.

A device for monitoring a discrete communication channel operates as follows.

When the device is turned on from bus 1, the Reset signal is sent through the second element OR 5, which sets the normalizing counter 3 and the counter 7 of the truncation of the analysis interval to zero and the reverse code 6 in the reversing counter is equal to half the capacity of this counter (Kc

), at the exit of the former 11

guard interval there is no signal blocking keys 1 and 2 on the control inputs.

The basic ratio of the sequential analysis plan to take into account the dependence of the values of the threshold levels on the sample size when analyzing likelihood ratios can be represented as

U + K, n + S-n t V-K2-n + S.n, (l) where U, V, S are the coefficients of the solving

equations chosen based on the probability values of errors of the first CxL,

second | 3 kind and control error;

,, K are the approximating coefficients taking into account the dependence of the values of the lower and upper threshold levels on the sample size for the likelihood ratio, respectively;

m

- number of mistakes;

five

0 5 o

with

d

0

five

n is the sample size. Determining the state of the communication channel according to a sequential analysis plan involves counting the number of Sd errors and comparing it with the maximum permissible values (thresholds r and ai). If in time t, the number of errors does not exceed r, the channel is registered as healthy, if more than a, it is registered as faulty. If the error has occurred, the tests are continued. The communication channel monitoring interval is limited to the tuc time (during the truncation of the interval, the analysis, i.e., one of the solutions is made at this point. If by this time the number of errors is 5 g, a fault signal is generated

Others, otherwise a healthy signal is generated.

The basic ratio of sequential analysis (1) through obvious transformations can be represented as

 .m -U-S- n V-U-K -n.

This makes it possible to refuse to directly count the number of errors nij, and to operate with a functionally dependent on t, the value M td-i-3 P, the definition of which is implemented in the proposed device. The value of M is fixed in the reversible counter 6, and the values of n and R V-U-K n determine the values of the comparison thresholds of the first and second comparators 9 and 10.

Hence, the capacity of the normalizing counter 3 is determined by the value N, //, the capacity of the reversible counter 6 - Npj, // U-V // 5 and its initial

condition. (I u / where symbol

.// // the whole part of the number. The capacity of the counter 7 truncation of the analysis interval is chosen equal to Na U-V, based on the required reliability of the decision, and after the initial

 four

The installation of this counter from its direct outputs is removed a code, and from inverse - a code. Codes b and C are fed to the second inputs of the first and second comparators 9 and 10, respectively.

During operation of the device, clock pulses from the bus 12 clock pulses through the open first key 1 are fed to the summing input of the normalizing counter 3. Pulses thinned out at the counter 3 from its overflow output (Fig. 2a) are fed to the summing input of the counter 7 of the truncated analysis interval and to the subtractive the input of the reversible counter 6, the summing input of which receives the error signals through the second key 2 (fig.2b). On the second, the inputs of the first and second comparators 9 and 10 with a frequency that is a multiple of the arrival frequency of 3 clocks punctured by a normalizing counter and determined by the values of the coefficients K and K, the state of the bits of the counter 7 is truncated, dynamically varying values of the lower A and upper R threshold levels.

The first inputs of the first and second comparators 9 and 10 receive the code of the number M from the outputs of the reversible counter 6. If, then the output of the first comparator 9 generates a health signal that passes through the first element OR 4 and enters the channel health indication bus (FIG. marked), and at the same time, the passage through the second element OR 5 is fed to the installation inputs of the normalizing counter 3, the reversible counter 6 and the counter 7 truncating the analysis interval, thereby setting the device to its initial state.

If, then at the output of the second comparator 10 a malfunction signal is formed (fig. 2d marked), which is fed to the input of the protective interval generator 11 and the input of the second element OR 5. The protective interval former 11 generates a fault signal at the inputs of its first and second keys 1 and 2 signal prohibiting the passage

12

5 0 5 0

about 5

five

one

giving clock pulses and error pulses. At the same time, the channel fault signal enters the channel fault indication bus 16.

A channel health signal, even for dynamically varying threshold values for medium quality channels, can be generated at long intervals. To shorten this time, truncate the interval of consecutive analysis. For this, a counter 7 of the truncated analysis interval is applied. If through interN h and X n

time t, where TC is the period of the decimated clock pulses, no pulses appear at the outputs of the first or second comparators 9 and 10, then a pulse appears at the output of the decoder 8 (FIG. 2B), which forms a channel health signal, enters through the first element OR 4 into the bus 15 indicating the health of the channel and at the same time carries out the installation of the device in the initial state (figure 2, marked).

Claims (1)

Invention Formula Device for monitoring a discrete communication channel by aut. St. No. 1133677, characterized in that, in order to reduce the monitoring time and increase the monitoring reliability by dynamically controlling the threshold levels with an increase in the sample size, a first comparator is inserted between the outputs of the reversible counter and the second input of the first OR element, the second comparator included between the outputs of the reversible counter and the guard of the guard interval, the decoder connected between the main outputs of the truncation counter of the analysis interval and the first input of the first element OR, This additional outputs truncation analysis interval counter connected to the other inputs of the second comparator and the decoder, and outputs the main count truncation interval and analyzing connected to the other inputs of the first comparator. but  / 77 7 eat / / fawa / i uncontrollable AND Fy8.2 / - KoBi AffWH is OK f) .t Fig.Z