SU1425854A1 - System for remote monitoring of digital linear path - Google Patents

Abstract

The invention relates to telecommunications. The purpose of the invention is to improve the accuracy of control by enabling the prediction of the state of a digital linear path, reducing the evaluation time and reducing the energy consumed. The system is part of the terminal station (C) 1, in which Zl-ta # 1 of the monitored object are encoder 2, regenerators 3 forward and reverse directions and decoder 4. The system contains a key block 5, error detector 6, counter 7, attenuator 8, Mr. 9 igum, power key 10, decoder 11, shift register 12 ,. the control {counter 13, the telecontrol command shaper 14, the calculator 15 and the telecontrol channels 16 and the telecontrol 17 connected to the intermediate- {and C 18. At the 1st stage (the integral evaluation stage), a periodic measurement of the jamming margin is performed total controlled digital linear path by creating at the outputs of the precursors of the terminal C 1 normiroF (L

Description

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bath interference, allowing to estimate the non-value of the LSD of the entire path and its dynamics. In the case of approaching the LSD to the maximum permissible value, the system proceeds to the 2nd stage. This is the stage of local estimation, during which the numbers of regenerators 3 are found, which have a reduced TOR. In the intervals between the time intervals in which the integral evaluation of the LSD is performed, on the terminal С 1 pro1

The invention relates to telecommunications and can be used in telecommunication monitoring systems of digital systems; transmission of information.

The circuit of the invention is to improve the control accuracy by making it possible to predict the state of the digital linear path, reducing the evaluation time and reducing the energy consumption.

Figure 1 shows the structural electrical circuit of the tele.n.trol digital linear path system; FIG. 2 is a block diagram of the output algorithm.

A telecontrol system for a digital linear path, which is part of terminal station 1, on which the elements of the object to be monitored are encoder 2, forward and reverse regenerators 3 and decoder 4, contains a key block 5, an error detector 6, a counter 7, attenuator 3, noise generator 9, power switch 10, decoder 11, shift register 12, control counter 13, telecontrol command generator 14, calculator 15, telecontrol channel 16 and telecontrol channel 17 connected to intermediate stations 18.

The system works as follows.

At the first stage (integral assessment), a periodic measurement of the noise immunity margin of the entire monitored digital linear path is made by creating, at the outputs of the transmitters of the terminal stations, normalized interference, allowing

The measurement factor is path errors due to detected violations of the structure of the code used. To determine the LSD, an interfering effect is introduced on the terminating C1 by changing the structure of the transmitted code. A calibrated unbalance of the linear signal, inputted to the transmitting C by violating the mode alternation law during coding, is used as an interfering effect. 2 pcs.

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to estimate the value of the noise immunity margin of the entire path and its dynamics. In the case of approaching the noise immunity margin to the maximum permissible value, the proposed device proceeds to the second stage of the local estimation, during which the numbers of regenerators with reduced noise immunity margin are entered. In time intervals, in which the integral assessment of the noise immunity margin is carried out, the terminal error rate is measured at the terminal stations due to detected violations of the structure of the code used.

There are several methods for determining the noise immunity margin, but the most promising is one in which a disturbing effect is introduced at the terminal stations by changing the structure of the transmitted code. This method allows quite simply and without disturbing the communication to make an assessment of the noise immunity margin.

As is well known, codes that are balanced or partially balanced by a constant component are used to transmit digital information over channels with limited bandwidth to reduce the effect of intersymbol interference. These types of codes include the codes n, NB- (N + 1) B, NB- (N-1) B, etc. The most commonly used on the lines of a coaxial, optical, symmetric cable are codes of the class NB- (N + +1) B, which are binary

314

codes balanced by a constant component, in which blocks of N binary symbols are converted into blocks of N + 1 symbols. Coding devices of such systems are built with. by means of permanent memory devices, the memory of which is written to the conversion table. Thus, for example, for a 5B6B code, a two-mode table (sometimes, using parity, four-mode) is written in ROM, in which 16 five-bit words are uniquely encoded with 16 six-bit words that are balanced by the constant component, and 16 the remaining words are encoded, depending on the current value of the digital sum, by codewords with the unbalance amount of either + 2 or -2.

Thus, by controlling. the current value of the digital sum, the output signal is balanced by the clock component. Balancing provides a reduction in intersymbol interference arising from the inclusion of remote power supply transformers in the linear path and the presence of a low-frequency cut-off input uviliteli and amplifiers-proofreaders of regenerators.

It is possible to determine the stability margin of the digital linear path by using as a disturbing effect a calibrated unbalance of the linear signal inputted to the transmitting stations by disrupting the modulation law during coding.

In accordance with the general work program of the calculator 15, time intervals are formed which determine the frequency of checking the noise immunity margin of the entire dafra path. At the beginning of the control, the calculator 15 generates a signal controlling the operation of the control counter 13, and sets its recalculation coefficient, the value of which determines the number of modes modulation law N introduced by the calculator 15. At the second terminal station 1, the number of recorded errors is distributed Nj, information about which on channel 17 telecontrol enters the input of the calculator 15 of the first terminal pack

1, where a comparison is made of the total number of oi: nf6oK registered. with entered and calculated}} error error

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 N2 - N

T f

i 7. .T

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where Tj is the evaluation interval; f - clock frequency.

If K AOP, the computer generates a command to increase the recalculation coefficient to the control counter 13. This operation continues until K is a valid Cd, after which the conversion factor N is compared with the limit value. If N "i, the calculator 15 goes to the subroutine of determining the number of the regenerator, which has a reduced noise immunity margin. In this case, at the output of the telecontrol command generator 14, a code word is generated corresponding to the number of the first controlled regenerator, which via the telecontrol channel 16 enters the shift register 12, decoded by the decoder 11, as a result of which the power key 10 is triggered, which feeds to block 5 keys, 6 error detector, counter 7, noise generator 9 and attenuator 8. Then the auxiliary output of the controlled regenerator 3 is connected to the input of the detector 6 errors, and you od attenuator 8 - to an auxiliary input of the regenerator 3.

At the end of the connection procedure, the calculator 15 begins to generate commands that, through the decoder 1 1., Control the operation of the attenuator 8, - and provide in each time interval a stepwise increase in the noise level supplied to the auxiliary input of the regenerator 3 from the noise generator 9. As soon as in one of the time intervals the counter 7 overflows, the key block 5 switches off all the auxiliary inputs and outputs of the regenerator 3 and generates a pulse with which the power key 10 is triggered, which leads to power loss from blocks 5 to 10, and Kotorp channel 17 tele514

KOHTi oJbT interrupts the program of operation of the PC 13, which transfers to the regenerator noise immunity margin subroutine.

 the value of the margin is greater than the boundary, the calculator returns to the control subroutine, but begins with the generation of the number of the next controlled regenerator. The calculation results are printed out to document the monitoring process and stored in the calculator memory for later comparison.

Between measurements of the noise margin of the digital path to the input of the transmitter 15, C11 signal is received from the auxiliary output of the decoder 4, registering violations of the code structure during decoding, and an estimate of the coefficient

OSH11bok

where m | number of violations found

with tr u to t ur s to ode;

T | - the evaluation interval, calculated by the computa tion.

If the coefficient of the flashback K, approaches the limit value 105, a priority interruption of the program is performed, and the calculator 15 proceeds to an extraordinary measurement of the noise immunity of the linear path

The algorithm of operation is used; the title 15 is shown in Fig. 2. According to this algorithm of the beginning (block 19), time intervals T are formed - the period of the integral assessment of the noise immunity margin of the linear path; T is the interval for estimating the coefficient oimbok for violation of the code structure; T is the interval for estimating the error rate pr of the integral estimate of the noise immunity margin of the linear path; T is the evaluation interval when measuring the margin of immunity of an individual regenerator.

Next (block 20), the current time is compared with the start time of the integral assessment of the noise immunity margin of the path. At t 7 i nTj, s where n is an integer, the error rate coefficient K is estimated due to violation of the code structure (blocks 21-24). Otherwise (at t pTd), go to block 25, and the process starts .

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Integratively assessing the safety margin of the path with the help of a violation of the mode alternation law (blocks 25-29). It should be noted that the transition to block 25 may be ocyuiecTB-bounded even after evaluating the error coefficient for the violation of the code structure, if the condition К, 6К "(block 23) is not met, in block 30 the number of introducing N is compared with the Npp limit value. With N N 5, which corresponds to the normal functioning of the linear path, the value of N is printed (block 31) and a transition to block 20 occurs. Otherwise, N i N

etc

which corresponds

the reduction of the noise immunity margin of the linear path below the preset one, the calculator 15 is converted to the routine for determining the numbers of regenerators 3, possessing 1X a reduced noise immunity margin (blocks 32-40).

In this subroutine, blocks 32, 39, and 40 provide a consistent measure of the noise immunity margin of all regenerators 3, starting from the first (L 1) to the last (L L, where M is the number of regenerators between the two end stations),

In block 33, the initial value of the noise level introduced into the regenerator 3 is formed, and in block 34 a condition is checked that registers the overflow of the meter 7. If Kg 1, i.e. in this time interval of the error counter overflow, it did not go back, a stepwise increase in the noise level is performed (block 35), and in the next time interval the status of counter 7 is checked again (block 34). When the counter 7 (K 1) overflows, the evaluation process ends and in block 36 the measured value of the noise immunity margin u, Sj is compared with the boundary value Srp-.

If & 5ts: S, the value of D. Sj is output to print (block 38) and the transition to measuring the susceptibility margin of the next regenerator 3 (blocks 39 and 40) occurs; Otherwise, the calculator 15 signals a decrease in the noise immunity margin in this regenerator 3 (block

37), and then continues to check the remaining .regenerators 3, also the transition to blocks 39 and 40,

Claims (1)

Invention Formula A system for telecontrol of a digital linear path containing each terminal station I connected computer and a telecontrol command driver, the output of which through the remote control channel is connected to the first input of the transmitter of another terminal station, and at each end station and intermediate station - a block of keys, the first and second inputs of which are the inputs for connecting the auxiliary outputs of the corresponding controlled oscillators linear path, the counter and shift register, the input of which is connected to the output of the telecontrol command generator via the telecontrol channel, characterized in that, in order to increase control by providing the ability to predict the state of the digital linear path, reducing the evaluation time and reducing the energy consumed, a control counter is introduced at each end station, the first input of which is connected to the second output of the calculator, and the second input and output are respectively the output and input the control signals of the encoder of the monitored digital linear path, an error detector is inserted at each endpoint and intermediate station, connected between the first output of the key block and info A counter input, the output of which is connected to the third input of the key block, serially connected noise generator and attenuator, the output of which is connected to the fourth input of the key block}, the second and third outputs of which are the auxiliary signals of the regenerators of the controlled digital linear path, serially connected decoder and key power, the output of which is connected to the fifth input of the key block and to the power inputs of the error detector, counter, noise generator and attenuator, another key input Itani connected to the fourth output of shift keys telecontrol unit and via the first input channel calculator, the output register is connected to the decoder input, the other output is connected to the control input of the attenuator and the second input of the calculator is the corresponding decoder output controlled digital linear path. ./sР-/Д vJHipHupoBaMue & / feHMfx imta fcfP67 ,, ff, T3.Tf -aTi. , 6ixfoff camowest, fashion iffffft / u "ode L R noffcvem vucfa ou / uSoft t r ..fSLif Hem - jj-I 6bi8i} dMO A ntvamtt A5L