SU1254587A1 - Device for checking linear path of digital transmission system - Google Patents

Abstract

The invention relates to telecommunications and provides enhanced functionality by registering two-level and multi-level linear signal failures. The signal from the antenna 1 installed in the immediate proximity to the points of information about the linear signal through the block 2 input, the amplifier-limiter 3, band-pass filter 4 and detector 5 enters the low-pass filter (LPF) 6. The band-pass filter 4 selects the frequency components in the spectrum of a linear signal in the event of a failure. Low-pass filter 6 causes a low-frequency component of the signal, which carries information about faults. From this signal, the threshold element 7 generates pulses corresponding to the failure. The fault counter 8 counts them, and the result is fixed by the indicator 9. With the help of the reference generator 15, the time generator 16, the time stamp counter (COB) 17, the force generator 18 of the reset pulses periodic reset of the counter 8 failures. The COB 17 forms a sequence of pulses with a predetermined follow-up period, which depends on the speed of information transfer. In particular, the switch 14 is used to change its separation factor and rebuild the bandpass filter 4 and #Ch 6 by means of voltage regulators 12, 13 and adjustment elements 10, 11. 1 sludge. § (Ls | 1 ate

Description

The invention relates to telecommunications and can be used in the equipment of the linear path of the digital transmission system (DSP).

The purpose of the invention is to expand the functional capabilities by registering failures of two-level and multi-level linear signals.

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

A device for monitoring a linear path of a digital transmission system comprises an antenna 1, an input unit 2, a limiting amplifier 3, a band-pass filter 4, a detector 5, a low-pass filter 6 (LPF), a threshold element 7, a fault counter 8, an indicator 9, the first and second elements TO and 11 are the first and second voltage regulators 12 and 13, an adjustment limit switch 14, a reference generator 15, a driver of 16 time stamps, a counter of 17 time stamps and a driver of 18 reset pulses.

The device works as follows.

The linear signal of the monitored path of the chain, the passage through the lead-through device of the intermediate point or terminal station, causes electromagnetic radiation, the level of which is sufficient for using the antenna coverage area. The transmitting antenna in this case is the installation of an intermediate or terminal station. The field of the transmitting antenna acts on the forward antenna 1, imposing a linear signal voltage on it. Antenna 1 is a frame mounted on a special holder that must be installed in the immediate vicinity of cable glands, line boxes or other points of information about the linear signal. The specified voltage is applied to input block 2, similar to the input stage of a radio receiver, which provides pre-amplification and filtering of the input signal and the coupling of antenna 1 to limiting amplifier 3. Input block 2 is a pre-broadband low-noise amplifier that provides matching antenna 1 with the input of the amplifier-limiter 3, as well as the protection of the device from dangerous

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545871

and interfering influences. The amplified signal of the normalized amplitude from the output of the limiting amplifier 3 of the amplifier is fed to a band-pass filter 4, which is designed to isolate the frequency components appearing in the spectrum of a linear signal in the event of a malfunction. An analysis of the energy spectra of two and three-level linear signals showed that in case of failure of these signals, leading to a violation of the linear code algorithm, an aperiodic change (deformation) of the energy spectrum of the linear signal occurs, which can be detected by filtering it and then amplifying it. - a tedious detection of the V-band with a 1-band filter of the frequency composition. Depending on the type of linear signal and the nature of its failures, the average frequency and bandwidth of the band-pass filter 4 are selected, as well as the load time constant of the amplitude detector, which uses the FHP 6 signal. The low-frequency component of the signal, carrying information about the fault, is with low pass filter 6 and enters the threshold

30 is an element 7 forming rectangular pulses with a normalized amplitude and duration depending on the duration of the interfering effect. Each such pulse corresponds to 35 in the linear signal of a single fault or a group (package) of failures, which will be followed in the course of a series of single feeds. The output signal of the threshold element 7 is fed to the counter 40 fault 8, which is a binary-ten counter, the output of which is connected to the indicator 9. The indicator 9 can be performed on the basis of an LED matrix having a circuit

4 $ control, providing periodic display of the number of pulses on the light board, which was recorded by the counter 8. To ensure a clear display of readings

50 at different values of the pusaigbq coefficient, the indicator should have at least four digits: units, tens, hundreds and thousand, which allows controlling the error rate in

About 5

55 limits from 10 to 1P. Counter B failures are non-periodically reset (set to zero), for which the counter reset input is periodically

An appropriate signal is output from the generator of the 18 reset pulses. The imaging unit 18 selects the reset pulses according to commands coming from the output of the counter 17 time stamps. The function of the time stamp counter 17 is to form a sequence of pulses with a predetermined follow-up period, and the period may vary depending on whether the transfer system is served, i.e. from the speed of information transmission over the controlled linear path of the chains. The period change is made by changing the division ratio of the counter 5, 17, i.e. switching elements of its scheme. The specified switching is carried out by an adjustment limit switch H, which is a manual control switch, 20 which has a number of positions, each of which corresponds to a certain CBMT

transfer speeds (for example, 2048,

with

 , kbps 25

8448, 34368). Switch

The 14 adjustment limits are connected to the first and second voltage regulators 12 and 13, which form a constant control voltage supplied respectively to the first banding adjustment element 10 of the bandpass filter 4 and to the second bass frequency adjustment element 11. .

35

Bandpass Tuning 4

and low-pass filter 6 makes it possible to significantly expand the range of measurements and make the proposed device universal within the limits of existing and implemented chains.

Tuning the amplitude-frequency characteristics of the bandpass filter 4

and the low-pass filter 6 is made on the basis of the elements45 of a reset pulse shaper, under the change of reactive impedance (varicaps, varistors, etc.). The voltage regulators 12 and 13 control the control voltage of the voltage supplied to the adjustment elements 10 and 11, t, Q, and contain a precision source, voltage and switchable dividers.

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Order 4729/58 Edition 624

Random polygons pr-tie; Uzhgorod, st. Project, 4

874

As a reference oscillator 15, a harmonic oscillator on a transistor with a quartz frequency stabilization can be used. The harmonic oscillation from the output of the reference generator 15 is supplied to the shaper of 16 time stamps, which produces a sequence of rectangular pulses fed to the counter 17.

Claims (1)

Invention Formula Control device for control a linear path of a digital transmission system comprising a time stamp counter, a serially connected amplifier-limiter, a band-pass filter detector, a low-pass filter, a threshold element and a failure counter and successively connected reference oscillator and a time stamp generator, characterized in that in order to expand the functional capabilities by registering failures of two-level and multi-level linear signals, a reset pulse shaper, an indicator, successively United Antenna and bl to the input, serially connected adjustment limit switch, first voltage regulator and first adjustment element and serially connected second voltage regulator and second adjustment element, with the output of the input unit connected to the input of the limiting amplifier, the outputs of the first and second elements nc "KJH04eHM adjustments to the control inputs of the band-pass filter and the low-pass filter, respectively, the output of the time stamp generator via serially connected time stamp counter and The key is connected to the reset input of the fault counter, the output of which is connected to the input of the indicator, and the second and third outputs of the overshoot limit of the adjustment are connected respectively to the input of the second voltage regulator and to the control input of the time stamp counter. Subscription