SU372736A1 - ALL-UNION I Pisht || o ~ 1pshg: r: sh! - Google Patents

Description

The invention relates to communication paths with redundant communication channels.

Telecontrol devices are known for switching redundant communication channels of a data transmission path, which include devices for monitoring the state of communication channels, switching devices and a remote control channel (TU) for transmitting and receiving commands for replacing a backup channel. TU systems using voice-guidance (TT) channels have two drawbacks:

1) low efficiency;

2) long switching time, affecting the reliability parameters of high performance paths.

The proposed device is characterized in that, in order to increase the reliability of the path, a backup link is used as a telecontrol channel and monitoring devices of the state of the communication channels, the transmitter output of the channel part of the transmission equipment is connected to the transmitting and receiving branches of the path data of one station and a monitoring device for a backup communication channel of another station, which isolates the voltage of the control (carrier or side) frequency of the equipment that was previously switched on This is a continuous channel, and ensures the formation of a command, through which the switching device of this station connects the equipment also to the backup communication channel.

The control device of the backup channel contains a frequency discriminator, the output of the selection of the control frequency voltage of which, through the contacts of the switching device, directly controls the switching of the equipment to the backup channel

connection and connected through a prohibition on a single input, and then through the normally open contacts of the main relay and the differentiating chain - to the zero input of the trigger, which controls the operation of the main relay for the switching time of the backup channel at two end stations. The second output of the frequency discriminator — the output of the voltage signal voltage selection — is connected through the common circuit to the switching inputs to the first or second communication channel through the amplifier and the contacts of the switching device.

This combination of transmitter channel equipment, backup link and

The backup channel control device allows:

1) to achieve a high reliability of the allocation of the teleunderstand command to the non-switching of the backup channel on the opposite

stations, since the probability of a false allocation of a remote control command is practically zero;

2) to exclude from the structure of the path specially designated communication channels for the transmission of telecontrol commands for switching back-up channels, which is the economic effect.

The drawing shows a block “o-functional diagram of a combined telecontrol system using backup channels of the data transmission path. The path is shown in the position of work on the first communication channel 1.

The proposed system includes the following elements:

- two channel part transmitters included in data transmission equipment 2 and 3, which convert a discrete sequence of message pulses into a modulated signal. Each transmitter is used only at the moment of switching the backup communication channel as a source of control (carrier) frequency. When switching the backup channel at one of the end stations, modulation of the carrier frequency is stopped for the time of switching by breaking the request signal circuit to the subscriber 6 or 7 by the contacts of the circuit and breaking the service silencing modulating carrier in the absence of information combinations from the subscriber;

- two switching units 8 and I connecting equipment 2 and 3 to the first / or second 10 communication channel. Each switching unit includes a multi-contact polarized relay 11 or 12, which, when a signal is applied to one of its contacts 13 or 14, switches the channel information circuits of the equipment to the second or first communication channel;

- two control units of the state of the working communication channel 15 and 16, which control the channel by carrier level interruptions or by the probability of error. When the permissible interruption of the level or the specified probability of an error in one of the branches of the working communication channel is reached, the control unit 15 or 16 generates a command for the local switching of block 8 or 9 to the backup communication channel;

- reserve paths of the path / and 10, which are standard telephone links;

- two control devices of the backup communication channel, each of which performs the following functions:

- monitors the state of the backup link by the presence of a signal frequency level. If necessary, by modulating the signal frequency with a discrete sequence, you can monitor the status of the backup channel by confidence;

- forms a command to switch the equipment of the opposite station to the backup communication channel and provides reverse control of this switch to any of the stations of the path;

- performs logical functions, namely: it provides switching of equipment 2 and 3 to an operative backup communication channel;

- uses reserve drop connection for remote control operations only

at the time of transmission and formation of a remote control command.

To perform these functions, each control unit of the backup channel contains: - a signal frequency generator 17, which is a conventional sinusoidal oscillator;

-frequency discriminator 18 (19) for isolating voltage / carrying one output and voltage / s on the other, which is a three-loop bandpass filter, the first circuit of which is connected to the communication channel and the other two are tuned to frequencies / carrier and / cv- The AC voltage produced by these circuits is rectified with successive detectors and provided as main control signals;

- the trigger 20 (21), which fixes the switching time interval of the backup communication channel at two terminal stations.

The executive element of each control unit is the main relay 22 (23),

controlled by trigger 20 (21).

The coincidence circuits 24 (25) and 26 (27) ensure the passage of a switching command from the output of the control units 15 (16) to the input, respectively, through contacts 13 or 14

if at the second inputs of these circuits there is a signal of a healthy state of the backup communication channel coming from amplifier 28 (29). Diodes 30-37 serve as isolation elements. The principle of operation of the remote control system

is as follows. Assume that, when transmitting information over a working communication channel / control equipment 15, one of the terminal stations recorded an emergency condition of the channel. In this case, the output of the first communication channel / through the contacts of the relay 11 in position 13 to the input of the matching unit 26 is sent a command to switch the equipment 2 to the backup channel 10. If the channel is healthy, the command coming to the input of contact 14 of the relay 11 (12) switches its contact system to position 14.

When equipment 2 is connected to the input of the communication channel, from the transmitter output of the channel part, the carrier frequency / carrier enters the transmitting branch of channel 10.

sets it to the unit and provides the triggering of the relay 22, breaking all the circuits switched by its contact system. This makes it possible to disable the receiving branch of the emergency channel 1 by contacts 39-40.

from discriminator 18 so that it doesn't happen