JP3049013B2 - Transmission system - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a transmission system, and more particularly, to a transmission system having a duplex wired transmission path.

[0002]

2. Description of the Related Art FIG. 5 is a block diagram showing an example of the configuration of a conventional transmission system having a duplex wired transmission line.

In this conventional example, as shown in FIG. 5, a plurality of radio stations 120-1 to 120-n are connected to duplicated wired transmission lines 130-1A to 130-nA and 130-1B to 130-n.
The control station 110 is connected to each of the plurality of wireless stations 120-1 to 120-n via nB, and transmits and receives signals to and from the wireless stations 120-1 to 120-n.

Each of the radio stations 120-1 to 120-n transmits and receives signals to and from the control station 110, and transmits and receives signals to and from the control station 110. Changeover switches 123-1 to 123-n for switching to one of two transmission paths
And the control units 121-1 to 121-n that monitor the states of the two transmission paths and control the operations of the changeover switches 123-1 to 123-n based on the states of the transmission paths, and the two transmission paths Each of them is constituted by disconnection lamps 122-1 to 122-n which indicate that the connection is in a disconnected state.

[0005] The control station 110 communicates with each of the radio stations 120-
Control switches 113-1 to 113-n for switching a transmission path used for transmitting and receiving signals to and from 1 to 120-n
Transmission line 13 between the wireless stations 120-1 to 120-n
0-1A to 130-nA, 130-1B to 130-nB
And the control unit 111 that controls the operation of the control switches 113-1 to 113-n based on the state of the transmission line, and the two transmission lines in one wireless station were both in a non-conductive state. And a disconnection lamp 112 indicating that case.

In the transmission system configured as described above, the control switches 113-1 to 113-n operate under the control of the control unit 111 in the control unit 110, whereby the transmission lines 130-1 A to 130-nA are operated. ,
The states of 130-1B to 130-nB are monitored.

In each of the radio stations 120-1 to 120-n, the changeover switches 123-1 to 123-n operate under the control of the control units 121-1 to 121-n. -1A to 130-n
A, the states of 130-1B to 130-nB are monitored.

Here, for example, it is assumed that a control signal is transmitted from the control station 110 to the radio station 120-1.

In the control unit 111 in the control unit 110,
When it is detected that the transmission path 130-1A is disconnected,
The operation of the control switch 113-1 causes the transmission path 130-
The control signal is transmitted using 1B.

The control unit 121 in the wireless station 120-1
Since the transmission path 130-1A is also detected to be disconnected at -1, the control signal is received using the transmission path 130-1B by the operation of the changeover switch 123-1.

[0011]

However, in the conventional transmission system as described above, it is necessary to provide control switches for the number of radio stations in the control station. However, there is a problem that the size of the system is increased and the expansion of the system is complicated.

Further, when a control switch serving as an interface for each radio station is closed due to a failure or the like, there is a problem that the radio station and the control station are disconnected.

[0013] The present invention has been made in view of the above-mentioned problems of the conventional technology. Even when a radio station is newly added, the control station does not become large and two control stations are required. An object of the present invention is to provide a transmission system capable of securing a transmission path to a wireless station even when an interface of one of the transmission paths is blocked due to a failure or the like.

[0014]

In order to achieve the above object, the present invention provides a plurality of radio stations and two radio stations per radio station.
A control station connected to each of the plurality of wireless stations via a wired transmission path composed of book transmission paths , between the plurality of wireless stations and the control station via the wired transmission path. In a transmission system for transmitting and receiving signals, the control station may determine whether one of the two transmission paths is
One of the transmission lines connected to the plurality of wireless stations;
A first switching means for selecting the transmission line, and
The other transmission path is connected to the plurality of radio stations.
A second switching unit for selecting one of the transmission lines ; monitoring a state of the transmission line;
And controlling the selection of the transmission path in the second switching means.
Control means, and monitoring of the state of the transmission line by the control means
Storage means for storing a result, wherein the control means comprises:
Based on the monitoring result stored in the storage means, the first
And controlling the selection of the transmission path in the second switching means.
Characterized in that that.

[0015]

[0016]

(Operation) In the present invention configured as described above, the first switching means switches the first transmission line between all of the duplicated wired transmission lines and all the radio stations. In addition, since the second switching unit switches the second transmission line between all of the duplexed wired transmission lines and all of the wireless stations, a new wireless station is added. In this case, there is no need to newly provide a switch for switching the transmission path, and the control station does not become large.

Further, even when one of the switching means is closed due to a failure or the like, signals are transmitted and received to and from the wireless station via the other switching means.

[0019]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram showing an embodiment of the transmission system of the present invention having a duplex wired transmission line.

In this embodiment, as shown in FIG. 1, a plurality of wireless stations 20-1 to 20-n are connected to a duplex wired transmission path 30-n.
1A to 30-nA and 30-1B to 30-nB are connected to each of the plurality of wireless stations 20-1 to 20-n,
The control station 10 transmits and receives signals to and from the wireless stations 20-1 to 20-n.

Each of the radio stations 20-1 to 20-n
Transmission / reception units 24-1 to 24-n for transmitting / receiving signals to / from the control station 10 and a changeover switch 23-1 for switching transmission / reception of signals to / from the control station 10 to one of two transmission paths. And a control unit 2 that monitors the states of the two transmission paths and controls the operations of the changeover switches 23-1 to 23-n based on the states of the transmission paths.
1-1 to 21-n, and non-communication lamps 22-1 to 22 to indicate that both of the two transmission paths are non-communicable.
-N.

The control station 10 is connected to each of the radio stations 20-1 to 20-1.
20-n, which is the first transmission path group which is the transmission path 3
A time-division switch 13a, which is a first switching means for switching between 0-1A to 30-nA, and radio stations 20-1 to 20-
transmission line 30-1 which is a second transmission line group between
Transmission paths 30-1A to 30-nA, 30-1B to 30 between the time division switch 13b, which is the second switching means for switching B to 30-nB, and the radio stations 20-1 to 20-n. −
The control unit 11 monitors the state of nB and controls the operation of the time-division switches 13a and 13b based on the state of the transmission path. When the two transmission paths in one wireless station are both disconnected, Disconnected lamp 12 indicating that
And the transmission paths 30-1A monitored by the control unit 11
The transmission path state memory 14 is a storage unit for storing states of 30-nA and 30-1B to 30-nB.

The operation of the transmission system configured as described above will be described below.

First, the transmission path 30-1 in the control station 10
The monitoring operation of A to 30-nA and 30-1B to 30-nB will be described.

FIG. 2 shows transmission lines 30-1A to 30-nA, 3 by the control station 10 in the transmission system shown in FIG.
It is a flowchart for demonstrating the monitoring operation of 0-1B-30-nB.

The time division switch 13a operates under the control of the control unit 11 in the control station 10, whereby the transmission path 30-1A and the control unit 11 are connected, and the transmission path 30-
The state of 1A is monitored (step S101).

Next, the monitoring result in step S101 is stored in the transmission path 30-1A area in the transmission path state memory 14 (step S102).

Next, the time division switch 13b operates under the control of the control unit 11 in the control station 10, whereby the transmission line 30-1B and the control unit 11 are connected, and the state of the transmission line 30-1B is changed. Is monitored (step S10
3).

Next, the monitoring result in step S103 is stored in the transmission path 30-1B area in the transmission path state memory 14 (step S104).

Transmission line 30- connected to radio station 20-1
When the monitoring of 1A and 30-1B is completed, the wireless station 2
The operation shifts to the monitoring operation of the transmission paths 30-2A and 30-2B connected to 0-2 (step S105).

The time division switch 13a operates under the control of the control unit 11 in the control station 10, whereby the transmission line 30-2A and the control unit 11 are connected, and the transmission line 30-
The state of 2A is monitored (step S101).

Next, the monitoring result in step S101 is stored in the transmission path 30-2A area in the transmission path state memory 14 (step S102).

Next, the time division switch 13b operates under the control of the control unit 11 in the control station 10, whereby the transmission line 30-2B and the control unit 11 are connected, and the state of the transmission line 30-2B is changed. Is monitored (step S10
3).

Next, the monitoring result in step S103 is stored in the transmission path 30-2B area in the transmission path state memory 14 (step S104).

Transmission line 30- connected to radio station 20-2
When the monitoring of 2A and 30-2B is completed, the wireless station 2
The operation shifts to the monitoring operation of the transmission paths 30-3A and 30-3B connected to 0-2 (step S105).

By repeating the above operation, the transmission lines 30-1A to 30-nA, 30-1B to 30
The state of -nB is monitored, and those states are stored in a predetermined area in the transmission path state memory 14.

Next, the control station 10 sends the radio stations 20-1 to 20-2.
An operation of transmitting a control signal to 0-n will be described.

FIG. 3 is a flowchart for explaining the operation of transmitting a control signal from control station 10 to radio station 20-1 in the transmission system shown in FIG.

First, the transmission paths 30-1A to 30-3 shown in FIG.
After monitoring 0-nA, 30-1B to 30-nB (step S201), if there is a control signal to be transmitted to the wireless station 20-1 (step S202), the transmission path state memory 14 The state of the transmission path 30-1A stored in the transmission path 30-1A area is extracted (step S20).
4).

Next, based on the state of the transmission path 30-1A extracted from the transmission path state memory 14, the transmission path 30-1
It is determined whether it is possible to transmit a control signal to wireless station 20-1 via A (step S204).

When it is determined in step S204 that a control signal can be transmitted to the wireless station 20-1 via the transmission path 30-1A, the time division switch 13a operates under the control of the control unit 11. Thereby, the control unit 11 is connected to the transmission line 30-1A, and the transmission line 30-A
A control signal is transmitted to wireless station 20-1 via 1A (step S205).

In step S204, the transmission path 30-
If it is determined that it is not possible to transmit a control signal to the wireless station 20-1 via the transmission line 1A, the transmission line 3 stored in the transmission line 30-1B area in the transmission line state memory 14
The state of 0-1B is extracted (step S206).

Next, based on the state of the transmission line 30-1B extracted from the transmission line state memory 14, the transmission line 30-1
It is determined whether it is possible to transmit a control signal to wireless station 20-1 via B (step S207).

If it is determined in step S207 that a control signal can be transmitted to the wireless station 20-1 via the transmission line 30-1B, the time division switch 13b operates under the control of the control unit 11. Thereby, the control unit 11 and the transmission line 30-1B are connected, and the transmission line 30-
A control signal is transmitted to the wireless station 20-1 via 1B (step S208).

In step S207, the transmission path 30-
If it is determined that it is not possible to transmit a control signal to the wireless station 20-1 via the wireless station 1B, the interruption lamp 12 is turned on by the control of the control unit 11, and the wireless station 20-
The operator is notified that the transmission paths 30-1A and 30-1B to No. 1 are disconnected (step S209).

After the control signal is sent to the wireless station 20-1 or the non-operation lamp 12 is turned on, the process returns to step S201.

Next, the operation of the radio stations 20-1 to 20-n will be described.

FIG. 4 is a flowchart for explaining the operation of radio station 20-1 shown in FIG.

First, the changeover switch 23-1 is switched to the transmission line 30-1A side by the control of the control unit 21-1 (step S301), and a control signal is received from the control station 10 via the transmission line 30-1A. It is determined whether or not it is possible (step S302).

When it is determined in step S302 that the control signal can be received from the control station 10 via the transmission line 30-1A, it is detected whether the control signal is transmitted from the control station 10. (Step S30
3).

When the control signal from the control station 10 is detected in step S303, the control signal from the control station 10 is received via the transmission line 30-1A (step S30).
4).

In step S302, the transmission path 30-
If it is determined that it is not possible to receive the control signal from the control station 10 via the control unit 1A, the control unit 21-1 controls the changeover switch 23-1 to switch the transmission path 30-1.
The transmission path is switched to the B side (step S305).
It is determined whether it is possible to receive a control signal from control station 10 via -1B (step S306).

If it is determined in step S306 that the control signal can be received from the control station 10 via the transmission line 30-1B, it is detected whether the control signal has been transmitted from the control station 10. (Step S30
7).

If the control signal from the control station 10 is detected in step S307, the control signal from the control station 10 is received via the transmission line 30-1B (step S30).
8).

In step S306, the transmission path 30-
If it is determined that it is not possible to receive the control signal from the control station 10 via the control station 1B, the interruption lamp 22-1 is turned on by the control of the control unit 21-1 and the transmission line 30 to the control station 10 is turned on. -1A and 30-1B are notified to the operator (step S309).

Incidentally, after the control signal is received from the control station 10, when the control signal is not transmitted from the control station 10 via the transmission lines 30-1A and 30-1B, or when the interruption lamp 22-1 After is turned on, the process returns to step S301.

[0058]

As described above, in the present invention,
First switching means for switching the first transmission line between all wireless stations in the duplicated wired transmission line, and second switching means for switching between all the wireless stations in the duplicated wired transmission line; The second switching means for switching the transmission path is provided, so that even when a radio station is newly added, it is not necessary to newly provide a switch for switching the transmission path, and the control station becomes large. Disappears.

Further, even when one of the switching means is blocked due to a failure or the like, a signal can be transmitted / received to / from the wireless station via the other switching means, and a highly reliable redundant system can be constructed. Becomes possible.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an embodiment of a transmission system of the present invention having a duplex wired transmission path.

FIG. 2 is a flowchart for explaining an operation of monitoring a transmission path by a control station in the transmission system shown in FIG. 1;

FIG. 3 is a flowchart illustrating an operation of transmitting a control signal from a control station to a wireless station in the transmission system illustrated in FIG. 1;

FIG. 4 is a flowchart for explaining the operation of the wireless station shown in FIG. 1;

FIG. 5 is a block diagram illustrating a configuration example of a conventional transmission system having a duplex wired transmission path.

[Explanation of Signs] 10 control station 11, 21-1 to 21-n control unit 12, 22-1 to 22-n disconnection lamp 13a, 13b time division switch 14 transmission line state memory 23-1 to 23-n changeover switch 24-1 to 24-n transmission / reception units 30-1A to 30-nA, 30-1B to 30-nB
Transmission line

Claims (1)

(57) [Claims] 1. A plurality of radio stations and one radio station
A control station connected to each of the plurality of wireless stations via a wired transmission path including two transmission paths; and a control station connected between the plurality of wireless stations and the control station via the wired transmission path. In the transmission system for transmitting and receiving signals in the control system, the control station may perform the transmission on one of the two transmission paths,
One of the transmission paths connected to the
A first switching unit for selecting one of the two transmission paths and the other transmission path.
One of the transmission paths connected to the
A second switching unit for selecting a state of the transmission line, and monitoring the state of the transmission line.
Control for controlling selection of the transmission path in the second switching means
Means for storing monitoring results of the state of the transmission line by the control means.
And a storage unit that, the control unit, the stored monitoring result in the storage unit
The transmission in the first and second switching means based on the
A transmission system for controlling selection of a route .