JPS5820494B2 - repeater - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to improvements in repeaters, and particularly to enable master stations and remote stations to dynamically control transmission lines.

Conventionally, when configuring a 1-to-N data transmission system using the repeater shown in Figure 1, which can perform regenerative relay in both directions, the repeaters are connected in series or cascaded as shown in Figure 2. It was connected.

Here, 100 and 101 in Figure 1 are left and right cables, 10
2, 103 is a left and right receiving section, 104 is an input gate, 105
1 is a regeneration relay section, 106 is a sampling pulse generation section, 1
07 is an output gate, 108 is a modulation section, 109 and 110 are left and right transmitting sections 111 are basic link generation sections, and 112 is a control section.

Further, 200 in FIG. 2 is a master station, 201.
202, 203, 204 are remote stations, 20
5.206.207.208°209 are repeaters shown in FIG.

According to the data transmission system shown in Figure 2, there are 210 transmission paths.
If there is a disconnection, the remote stations 203, 204 and the master station 200 beyond the disconnection point cannot transmit data.

Therefore, in recent years, in preparation for disconnection of the transmission line, one
A method has been adopted in which the system is configured in a loop using actual cables.

However, if the conventional repeater shown in FIG. 1 is applied as is, the following problems will occur.

(1) Once a station sends data, the data goes around the transmission path and returns to the data sending station.

Once that station sends out data, it then captures the data it sent and reproduces and relays it, resulting in the remaining data circulating around the transmission path indefinitely.

This is a problem that did not occur in the system shown in FIG. 2, and since the transmission line in FIG. 2 is interrupted at the master station 200 and remote station 204, the above-mentioned problem does not occur.

(2) In order to prevent self-transmitted data from being regenerated and relayed, it is possible to prohibit the relay operation for a certain period of time after data transmission, but if the transmission path becomes longer or the number of repeaters increases, The data delay in these cases varies, and if the worst value is set, there will be a drawback that efficient data transmission will not be possible.

(3) If the loop of the repeater at the master station is not broken, it is preferable to transmit from one direction rather than from both directions because data will not collide on the transmission path.

On the other hand, if a disconnection occurs, it is better to transmit from both directions.

Good.

The above drawbacks can be eliminated by changing the operating specifications of the repeater used at the master station and the repeater used at the remote station.

That is, the repeater at the master station can receive and transmit from both directions.

In the case of transmission, it is desirable to be able to dynamically perform transmission from one direction at a time.

However, changing the operational specifications of the repeater inevitably increases the number of types, which is economically undesirable.

In view of the above, in order to realize the data transmission system shown in FIG. 3, the operations of the repeaters cannot be fixed uniformly.

The role of a repeater is various, and a repeater that allows a master station and a remote station to control the transmission path is required.

300 in FIG. 3 is a master station, 301;

302, 303, 304, 305, 306, 307 are remote stations, 308, 309, 310° 311
．． 312, 313, 314, and 315 are repeaters.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a repeater that allows a master station and a remote station to dynamically control a transmission path.

The details of the present invention will be explained below with reference to FIG. 4 showing one embodiment thereof.
03 is a transmitter, 404, 405, 406 is an input gate, 404 is a gate that takes in the left received signal, 405 is a gate that takes in the right received signal, and the output of 406 is a regenerative relay part (ta). However, it is sent to the master station (not on the repeater).

407, 408, and 409 are output gates that send the data to the left transmitter 402;
08 is a gate for switching the modulation signal.

410, 411, and 412 are output gates that send data to the right transmitter 1 transmitter 403; 410 is a regenerative relay signal;
1 is a gate that switches the modulation signal.

Next, the operation of the circuit shown in FIG. 4 will be explained.

u, 416°417.418 comes from the control section inside the repeater? It's a signal.

According to the control signal 416, the received signal from the left receiving section 400 is sent to the regenerative relay section via the input gate 404,
The regenerative relay signal is sent to the transmitter 403 on the right side via the output game 4410.

Control signal 417 performs the opposite operation to control signal 1416 described above.

That is, the received signal from the receiving section 401 on the right side is regenerated and relayed and sent to the transmitting section 402 on the left side.

Control signals 416 and 417 are related to relay operations, and control signal 418 is for transmitting modulated signals of data sent from the station to which this repeater is connected in both left and right directions.

Control signals 419 and 420 are for implementing the invention and are sent from the master or remote station to which the repeater is connected.

For example, when the master station repeater closes the control signal 419 from the master station, the left side of the repeater will not be able to receive data, and at the same time it will not be able to send regenerative relay signals or modulated signals to the left side. There will be no.

Similarly, a control signal) 420 prohibits transmission and reception on the right side, contrary to the control signal 419.

In this way, the input gate and output gate of the repeater can be controlled.
This device is characterized in that it can be controlled not only from the control unit inside the repeater but also from an external station to which the repeater is connected.

As is clear from the above, when the repeater of the present invention is applied to a data transmission system as shown in FIG. 3, the conventional drawbacks can be overcome as follows.

(1) The repeater of the master station can temporarily close either the control signal 419 or 420 from the master station in FIG. 4, and cut the transmission path. There is no drawback that the remaining data sent from the remote station circulates around the transmission path indefinitely.

(2) Even if a disconnection occurs in the transmission line or a repeater at a certain remote station is unable to relay in one direction, the repeater at the master remote station uses control signals 419 and 420 to By opening the input gate of the system so that it can receive data input from both directions, data transmission can be performed without the system going down.

[Brief explanation of drawings]

Figure 1 is a circuit diagram of a conventional repeater, Figure 2 is a circuit diagram of a data transmission system in which the repeater shown in Figure 1 is directly connected to the relay, Figure 3 is a circuit diagram of a conventional loop data transmission system, and Figure 3 is a circuit diagram of a conventional loop data transmission system. FIG. 4 is a circuit diagram of a repeater according to the present invention. 400.401... Receiving section, 402, 403... Transmitting section, 404, 405, 406... Input gate, 40
7.408, 409, 410, 411.412... Output gate, 416, 417.418.419.420
···Control signal.

Claims (1)

[Scope of Claims] 1. A repeater connected to a loop transmission line that performs 1:N data transmission between a master station and a plurality of remote stations, including a left and right receiving section, a left and right transmitting section, and a left and right receiving section, a left and right transmitting section, and a The signal received by the receiving section is guided to the right transmitting section via the left input gate means, the regenerative relay section, and the first right output gate means. a first relay means; a second relay means for guiding the signal received by the right receiving section to the left transmitting section via the right input gate means, the regenerative relay section and the first left output gate means; The transmission signal is transmitted to the second left output gate means, the second
Right output via gate means. transmitting means for guiding the signal to the left and right transmitting sections;
a control section that controls the relay means and the transmission means; a first gate opening/closing means that controls opening and closing of the left input gate means, the first left output gate means, and the second left output gate means;
The right input gate means, th. 1 right output gate means and a second gate opening/closing means for controlling opening/closing of the second right output gate means, and the repeater of the master station prevents the data sent to the transmission line from endlessly circulating the transmission line. A repeater characterized in that either the first or second gate opening/closing means is brought into a closed state. 2. Claim 1 is characterized in that when a failure occurs in the transmission line or the remote station, the master station repeater receives data input from both directions through left and right input gate means. relay.