JPS6266733A - Duplex system for optical terminal station - Google Patents

Abstract

PURPOSE:To use effectively optical fibers by providing a means, which turns back the output pattern of a pattern generator from a stand-by light transmitting part to a stand-by light receiving part, and a means which connects a current light transmitting part and the standby light transmitting part to one light transmission line. CONSTITUTION:The transmission signal inputted from a terminal IN passes a changeover switch 10, a multiplexing part 1n, and a light transmitting part 2n and is converted to an optical signal and passes an optical switch 12 and an optical coupler 16 and is outputted to an optical fiber 22-1. Meanwhile, the reception signal from an optical fiber 22-2 passes an optical switch 19, an optical coupler 14, and an optical receiving part 3n and is converted to an electric signal and is sent to a terminal OUT. The output signal of a pattern generator 20 passes a light transmitting part 2s, an optical coupler 15, and a light receiving part 3s and is inputted to a pattern detecting part 21 to check the operation of each part. When a switching command is issued, the transmission signal and the reception signal are transmitted and received through the light transmitting part 2s and the light receiving part 3s.

Description

[Detailed Description of the Invention] [Summary] An optical switch, a coupler, and a pair of optical fibers are used to duplicate the multiplexing section and the optical-to-electrical conversion section, and a pattern is placed on the spare side to monitor the status.

[Industrial application field]

The present invention relates to a duplex system for optical terminal equipment.

Conventional redundant advanced station equipment configures the system using four optical fibers housed in one optical cable, which has the disadvantage of using too many optical fibers. Improvement was required.

[Conventional technology]

FIG. 3 is a diagram showing an example of a conventional optical terminal station duplex system.

In the figure, In and 1s are multiplexing sections, 2n and 2s are optical transmitting sections, 3n and 3s are optical receiving sections, 4n and 4S are demultiplexing sections, 5 is a switch, and 6 is an optical cable. The same symbols represent the same objects throughout all the figures below.

The conventional duplexing system for optical terminal equipment uses four optical fibers as shown in FIG.

On the transmitting side, the transmission signal is input in parallel to the working multiplexer 1n and the standby multiplexer 1s, and the output of the working multiplexer In is converted into an optical signal in the optical transmitter 2n. The signal is then output to the first optical fiber harrow 1 of the optical cable 6, and the output of the spare multiplexer 1s is converted into an optical signal in the optical transmitter 2s, and then sent to the second optical fiber 6-2 of the optical cable 6. Output.

On the receiving side, the optical signal from the third optical fiber harrow 3 of the optical cable 6 is received by the current optical receiver 3n, converted into an electrical signal, and then input to the current multiplexer/demultiplexer 4n. The optical signal from the fourth optical fiber harrow 4 of No. 6 is received by the current optical receiver 3s, converted into an electrical signal, and then inputted to the current multiplexer/demultiplexer 4s. It was outputting a 4n output signal.

[Problem that the invention seeks to solve]

However, in the conventional duplexing method described above, the multiplexing section (i
Although the optical cable 6 is considered to be more reliable than the optical cable 6, the demultiplexer (4n, 4s), the optical transmitter (2n, 2s), and the optical receiver (3n, 3s), The disadvantage of using four optical fibers 1 to 6-4 is that it is uneconomical.

[Means for solving problems]

As shown in FIG. 1, the means for solving the problem is to send an input data signal to a pattern generator 20, a pattern detector 21, and a working optical transmitter 2n, and send an input data signal to a backup optical transmitter 2s.
A first switching means transmits the output pattern of the pattern generator 20, outputs the output optical signal of the working optical transmitter 2n to the optical transmission line, and outputs the output optical signal of the backup optical transmitter 2s to the backup optical receiver. a second switching means for outputting the output signal of the working optical receiver 3n to a subsequent stage and sending an output signal of the standby optical receiver 3s to the pattern detector 21; By providing a first optical coupler that connects the optical transmitter 2s to a single tree optical transmission line, and a second optical coupler that connects the working optical receiver 3n and the standby optical receiver 3s to the single tree optical transmission line. resolved.

[Effect]

According to the present invention, it is possible to use two optical fibers to have exactly the same functions as conventionally performed using four optical fibers, and it is possible to effectively utilize optical fibers. This effect is produced.

〔Example〕

FIG. 2 is a diagram showing an embodiment of the optical terminal duplex system according to the present invention.

In the figure, 10.11 is a changeover switch, 12.13.19 is an optical switch, 14.15.16 is an optical coupler, and 17.18
20 is an attenuator, 20 is a pattern generator, 21 is a pattern detector, 22 is an optical cable, and 22-1, 22-2 are optical fibers accommodated in the optical cable 22, respectively.

The present invention will be described in detail below with reference to the drawings.

The changeover switch 10.11 both has its contact a connected to its contact S and its contact C connected to its contact d, but as the switching operation is performed, its contact A is connected to its contact d, and its contact C is connected to its contact d. Contact C is connected to contact S.

First, on the transmitting side, the transmitting signal enters from the terminal IN,
It enters contact a of the changeover switch 10. Since the contact a of the changeover switch 10 is connected to the contact S, the 1-key signal enters the multiplexer In, is multiplexed, enters the optical transmitter 2n, and is converted into an optical signal.

At this time, since the terminal a and the terminal A of the optical switch 12 are not connected, the optical signal output from the optical transmitter 2n enters the X terminal of the optical coupler 16.

Each of the optical couplers 14, 15, and 16 is composed of a half mirror or a prism, and is an optical element that serves as a kind of switch in which an optical signal input to its X terminal or X terminal is output to two terminals.

Since the X terminal of the optical coupler 16 is connected to the Z terminal,
The optical signal output from the optical transmitter 2n is output to the optical fiber 22-1 of the optical cable 22.

On the other hand, on the receiving side, the optical fiber 2 of the optical cable 22
The received optical signal sent from 2-2 enters the optical switch 19 and is input to the X terminal of the optical coupler 14 since its terminal a and terminal A are connected at this time.

At this time, since the optical coupler 14 has its X terminal and two terminals connected, the received optical signal is input to the optical receiver 3n, converted into an electrical signal, and input to the multiplexer/demultiplexer 4n. It is demultiplexed here and its output is connected to the terminals OU since the contacts a and b and the contacts C and d of the changeover switch 11 are connected respectively.
Sent to T.

- Note H shows the operating status of the equipment on the active side, but the equipment on the backup side is as follows.

The output signal of the pattern generator 20 passes through the contact C1 and the contact d of the changeover switch 10, enters the standby multiplexer 1s, is multiplexed, and is then converted into an optical signal in the optical transmitter 2s. The output of the optical transmitter 2s enters the optical switch 13. In the optical switch 13, both terminals a and 2 are connected, so the output signal of the butterfly generator 20 enters the attenuator 18, where it is attenuated and then input to the optical coupler 15.

Since the X terminal of the optical coupler 15 is connected to the Z terminal, the optical output of the attenuator 18 enters the optical receiver 3s, is converted into an electrical signal, and enters the backup demultiplexer 4S. The output of the demultiplexer 4S is input to the pattern detector 21 through the contacts d and C of the changeover switch 11, where it is checked whether or not it is operating normally.

When a switching command is issued, the switching switch 10.11 is activated as described above.
As mentioned above, the contact a is connected to the contact d, and the contact C is connected to the contact s.

Therefore, the transmission signal input from the terminal IN enters the a terminal of the optical switch 13 via the multiplexer IS and the optical transmitter 2s.

Since the terminals a and C of the optical switch 13 are not connected due to the switching command, the output of the optical transmitter 2s enters the X terminal of the optical coupler 16. Since the X terminal of the optical coupler 16 is connected to the two terminals by the switching command, the output of the optical transmitter 2s is output to the optical fiber 22-1 of the optical cable 22.

The optical signal sent from the optical fiber 22-2 of the optical cable 22 enters the optical switch 19, and since its terminals a and C are connected at this time, it is input to the X terminal of the optical coupler 15. At this time, since the optical coupler 14 has its X terminal and two terminals connected, the received optical signal is input to the optical receiver 3s, converted to an electrical signal, and then enters the multiplexer/demultiplexer 4S. It is demultiplexed here and its output is sent to contact a of the selector switch 11.
Since contact d and contact C are connected to each other, the signal is sent to the terminal OUT.

In this case, the equipment currently used at the training camp is a pattern generator 20.
As mentioned above, the output signal of is sent and monitored.

〔Effect of the invention〕

As described in detail above, the present invention has the great effect of being able to configure a duplex system using a pair of optical fiber cables.

[Brief explanation of drawings]

FIG. 1 is a diagram showing the principle of the present invention. FIG. 2 is a diagram showing an embodiment of a redundant optical terminal station system according to the present invention. FIG. 3 is a diagram showing an example of a duplication system for a conventional optical terminal equipment. In the figure, in and Is are multiplexing sections, 2n and 2s are optical transmitting sections, 3n and 3s are optical transmitting sections, 4n and 4s are demultiplexing sections, 5 is a switch, 6 is an optical cable, and 10.1
1 is a changeover switch, 12.13.19 is an optical switch, 1
4.15.16 is an optical coupler, 17.18 is an attenuator, 20 is a pattern generator, 21 is a pattern detector, 22
is an optical cable, and 22-1 and 22-2 are optical cables 2 and 22-1 and 22-2 respectively.
This is an optical fiber housed in 2. zQ Tree/Invention 5 Light Extinguishing Bureau Rat Toni Sho Kaho Ekiri 1 Implementation 5) 1
2nd Figure 11ffi, fl,! tJ18 duplication method 3n-@・1
”Figure 3

Claims (1)

[Claims] Sending input data signals to a pattern generator (20), a pattern detector (21), and a working optical transmitter (2n);
The pattern generator (2s) is used for the backup optical transmitter (2s).
0); a first switching means for outputting the output optical signal of the working optical transmitter (2n) to an optical transmission line; (3s), and a second switch for outputting the output signal of the working optical receiver (3n) to a subsequent stage and sending the output signal of the standby optical receiver (3s) to the pattern detector (21). means, the working optical transmitter (2n) and the standby optical transmitter (2n);
2s) to one optical transmission line, and a second optical coupler to connect the working optical receiver (3n) and the backup optical receiver (3s) to one optical transmission line. A redundant optical terminal system characterized by comprising: