JPS61264828A - Optical repeater at midpoint - Google Patents

Abstract

PURPOSE:To transmit a signal of a desired low-order group signal to an optical transmission line by using a synchronizing signal separated from an optical signal of a high order group in other direction so as to apply conversion when the optical signal of either incoming or outgoing high-order group is not received. CONSTITUTION:If a concerned station 16 does not receive a signal 1 of high- order group, the station 16 uses a synchronizing signal separated from an outgoing optical signal 4 and converts new m1-set low-order group signals inputted externally into a high-order group optical signal 2 and sends the result. Thus, even when the station 16 does not receive the high-order group optical signal 1, a synchronizing signal separated from the high-order group optical signal 4 in other direction is used, the m1-set low-order group signal inserted newly to the station 16 is converted into the high-order group optical signal 2 and sent to the optical path. Thus, even if a fault takes place in the optical path in the incoming direction between a WEST station 17 and he station 16, the communication path is ensured in the incoming direction from the station 16 toward an EAST station 18.

Description

[Detailed Description of the Invention] [Summary] Desired low-order group signals are extracted from received uplink and downlink high-order group optical signals, and desired low-order group signals are inserted respectively to generate high-order group optical signals. When sending each
Discloses a configuration capable of transmitting a high-order group optical signal by using a synchronization signal separated from a high-order group in the other direction when an optical signal of a high-order group in either the upstream or downstream direction is not received. has been done.

[Industrial application field]

In the present invention, when converting a high-order group optical signal into a low-order group signal and relaying it intermediately, if the high-order group optical signal in either the upstream or downstream direction is no longer received,
The present invention relates to an optical intermediate repeater configured to perform conversion using a clock signal separated from optical signals of higher order groups in other directions.

[Conventional technology]

Conventionally, received uplink and downlink optical signals of high-order groups are converted into low-order group signals, respectively, and desired low-order group signals are extracted from the converted low-order group signals, respectively. A new low-order group signal corresponding to the frequency band of the extracted low-order group signal is inserted and converted into a high-order group optical signal,
There is an optical intermediate repeater that transmits the converted high-order group optical signals to optical transmission lines. The optical intermediate repeater converts a high-order group signal into a low-order group signal, or converts a low-order group signal into a high-order group signal.

Synchronization signals separated from the received uplink or downlink higher-order group optical signals are fixedly used.

[Problem that the invention seeks to solve]

As mentioned above, in the conventional optical intermediate repeater, the synchronization signal separated from the optical signal of the higher order group received for the upstream or downstream direction to which the signal to be converted belongs is fixedly used. If an optical signal of a higher order group in either the upstream or downstream direction is not received due to any of the above reasons, the optical signal of the higher order group in that direction will no longer be transmitted. For this reason, in particular, a new low-order group signal is inserted into a low-order group signal obtained by converting the received high-order group optical signal, and the inserted low-order group signal is included, or the high-order group optical signal is When converting into a signal and transmitting it, since the high-order group optical signal from which the synchronization signal is extracted is not received, the low-order group signal to be newly inserted cannot be sent to the optical transmission path either. There was a problem with it being put away.

[Means for solving problems]

The present invention converts received uplink and downlink high-order group optical signals into low-order group signals, extracts desired low-order group signals from the converted low-order group signals, and extracts the desired low-order group signals. When inserting a new low-order group signal corresponding to the frequency band of the low-order group signal and converting it into a high-order group optical signal and transmitting each, the high-order group optical signal in either the upstream or downstream direction is inserted. By adopting a configuration that converts the signal using a synchronization signal separated from the high-order group optical signal in the other direction when the signal is no longer received, at least the low-order group signal to be inserted can be transferred to the optical transmission line. It is also C to enable transmission.

FIG. 1 shows a block diagram of the principle of the present invention.

In the figure, 1 and 4 are OR (optical receiver), 2 is drop/insert control unit, 3 and 5 are O3 (optical transmitter), 6-1.6
-2 is a fault detector, 7-L7-2 is 5YNC (synchronization separation circuit), 8-1.8-2 is PC (pulse generator), 9-
1.9-2 represents SW (switch).

[Effect]

In FIG. 1, a high-order optical signal (1) transmitted in the upstream direction is converted from an optical signal to an electrical signal by OR1. The converted high-order group signals are converted into a plurality of low-order group signals by the drop/insert control unit 2, and then
Only the desired low-order group signals are extracted to the outside as a DS3 signal (a signal obtained by multiplexing audio signals). On the other hand, the DS input from the outside to the Dronobu/insert control unit 2
3 signals are inserted and converted into higher order group signals. The converted higher-order group signal is converted into an optical signal by O33, and sent to the optical transmission line as an optical signal (2).

Similarly, for the high-order group optical signal (4) transmitted in the downward direction in FIG. After a low-order group signal is inserted by section 2 and O35, the signal is sent out to the optical transmission line as an optical signal (3) in the figure.

When converting a high-order group signal to a low-order group signal in the drop/insert control section 2 described above, and when converting a low-order group signal to a high-order group signal, the 5YNC7 is used for the drop/insert control section 2. A synchronization signal separated from the optical signal (11 or optical signal (4)) and a pulse from PG8-1.8-2 synchronized with the synchronization signal are supplied by -1 and 7-2. What are the synchronization signals and pulses?

Usually, it is used in a semi-fixed manner for uplink or downlink signals in which the respective synchronization signals are separated. This is done by setting the contacts of SW 9-1 on the lower side and the contacts of SW 9-2 on the upper side as shown in Figure 1.

However, if the optical signal (1) or the optical signal (4) is no longer received due to some reason, the failure detector 6-1, 6-2 detects that the optical signal (1) or the optical signal (4) is no longer received, and the sw, Either the contact of 9-1 is switched to the upper side, or the contact of SV/29-2 is switched to the lower side.

Thereby, conversion is performed using the synchronization signal separated from either the optical signal (1) or the optical signal (4) by the 5YNC 7-1 or 5YNC 7-2. For example, when the optical signal (1) is no longer received, the fault detector 6-1 switches the contact of SW 9-1 to the upper side and receives the synchronization signal separated from the optical signal (4) by the 5YNC 7-2. Supplied to PG8-1. As a result, the illustrated DS3 signal supplied from the outside to the drop/insert control unit 2 is inserted as a low-order group signal. Then, the inserted low-order group signal is converted into a high-order group signal, and sent to the optical transmission line as a high-order group optical signal (2) via 033.

〔Example〕

FIG. 2 shows a configuration diagram of one embodiment of the present invention.

In the figure, 10-1.10-2 is an S/P (serial to parallel converter), 11-1.11-2 is a 5EL (selector), and 12-1.12-2 is a P/S (parallel to serial converter). (variable mH), 13-1. 13-2 is DSTF
(destuffing), 14-1.14-2 represents STF (stuff), and 15-1.15-2 represents rNTF (interface). Note that 1 to 5 in 9 figures. 6-1. 6-
2. 7-1. 7-2°8-1. 8-2. 9-1
and 9-2 have the same functions as those shown in FIG.

In FIG. 2, an optical signal (1) in FIG. 2 is a high-order group optical signal, and optical-to-electrical conversion is performed by an OR (optical receiver) 1. The higher-order group signal subjected to the optical-electrical conversion is S
/PLO-1 converts into multiple low-order group signals,
It is input to SEL (selector) 11-1. On this occasion,
A synchronization signal that is separated by supplying the high-order group signal to the 5yNC (synchronization separation circuit) 7-1, and a P synchronization signal synchronized with the synchronization signal.
G (pulse generator) S based on the pulse from 8-1
/PLO-1 converts the high-order group signal to obtain a predetermined low-order group signal. Then, only a desired low-order group signal is selected from among the plurality of low-order group signals inputted to 5ELII-1, restored using DSTF (destuffing) 13-1, and INTF (interface) 15-1. 1 to the outside as a DS3 signal (a low-order group signal in which audio is multiplexed).

On the other hand, the DS3 signal to be inserted from the outside is INTF
5 through 15-2 and 5TF (Stuff 7) 14-1
Input to ELII-1. As a result, a new low-order group signal input from the outside corresponding to the frequency band of the low-order group signal taken out from the outside is inserted. and,
A series of low-order group signals including the inserted low-order group signals are input to P/512-1 and converted into high-order group signals. The converted higher-order group signal is converted into a higher-order group optical signal by O33, and is sent to the optical transmission line as an optical signal (2).

Similarly, OR4,5/PLO-2,5YNC7-2
, PO2-2, 5RLII-2, DSTF13-2 and INTF15-2 take out the DS.3 signal to the outside. Also, INTF15-1,5TF14-
2.3ELII-2゜P/5L2-2 and O35 insert a new low-order group signal into the frequency band of the low-order group signal taken out to the outside, and create a high-order group optical signal (3)
It is converted into and sent out to the optical transmission line.

The configuration and operation described above are for the case where the optical signal (11) and the optical signal (4) of the respective higher order groups are received in the upstream and downstream directions.On the other hand, due to some reason, the optical signal (1) Alternatively, if either the failure detector 6-1 or the failure detector 6-2 detects that one of the higher-order optical signals (4) is no longer received.

By switching the contacts of SW 9-1 or SW 9-2, conversion is performed using a synchronizing signal separated from optical signals of higher order groups in other directions. for example.

When the failure detector 6-1 detects that the optical signal (11) of the higher-order group in the upstream direction is not received, the failure detector 6-1 switches the contact point of SWl'3i to the upper side and receives the higher-order group optical signal in the downstream direction. The synchronization signal (SYNC2 signal) separated from the optical signal (4) of Although this is not the case, at least the DS3 signal input from the outside is
NTF15-2.5TF14-1.5ELII-1,P
/512-1 and 033, the higher order group optical signal (2
) and sent to the optical transmission line. In other words, all the uplink relay functions do not stop.

The low-order group signals directly input to the optical space relay device are converted into high-order group optical signals and sent out to the optical transmission line without being disturbed.

Similarly, in the downstream direction, when the fault detector 6-2 detects that the optical signal (4) of the higher order group is not received, the contact of SW29 2 is switched to the lower side, and the optical signal (4) of the higher order group in the up direction is (Using a synchronization signal (SYNCI signal) separated from 11.

At least a low-order group signal directly input to the optical space relay device is converted into a high-order group optical signal (3).

It is sent out to the optical transmission line.

FIG. 3 shows a system configuration diagram of the present invention. Authority 16 in the diagram
．． The WEST station 17 and the EAST station 18 are stations each using the optical intermediate repeater according to the present invention, and all authorities 16
The present invention will be explained in detail, focusing on the following.

In Figure 3, when no failure has occurred.

n low-order group signals (DS in the figure) transmitted from the WEST station 17 to the authority 16 via an optical path (for example, an optical cable)
The optical signal (1) of the higher order group, which is a multiplexed signal of
6 into a low-order group signal. Then, for example, m1 low-order group signals (DS3 signals) are extracted from the converted low-order group signals. On the other hand, m1 new low-order group signals (D33 signals) are newly inserted into the frequency band where the low-order group signals extracted to the outside were located.

Then, in addition to the inserted m low-order group signals, the n low-order group signals that simply pass through the authority 16 (nmt) are the high-order group signals. is converted into an optical signal (2) and sent to the EAST station 1 via the optical path.
8. Similarly, for the downward direction, EAST
A higher order group optical signal (4), which is a multiplex of n lower order group signals transmitted from the station 18 to the authority 16 via the optical path, is converted by the authority 16 into a lower order group signal. Then, for example, m2 low-order group signals are extracted from the converted low-order group signals. On the other hand, m2 is newly added to the frequency band where the low-order group signal taken out to the outside was located.
Insert low-order group signals.

Then, in addition to the inserted m2 low-order group signals, n low-order group signals that simply pass through the authority 16 (nmz) become the high-order group signals. It is converted into an optical signal (3) and sent to the WEST station 1 via the optical path.
7.

In the system as described above, a failure occurs in the optical path in the upstream direction from the WEST station 17 to the authority 16, and the authority 1
6, when the high-order group signal (1) is no longer received, the authority uses the synchronization signal separated from the downstream optical signal (4) to receive m1 new low-order group signals input from the outside. The signal is converted into a higher-order group optical signal (2) and sent out. Therefore, even if the optical signal (1) of the higher-order group is not received by the authority 16, m, newly inserted into the authority 16 using the synchronization signal separated from the optical signal (4) of the higher-order group in the other direction. It is possible to convert the low-order group signals into high-order group optical signals (2) and send them to the optical path. Therefore, even if a failure occurs in the upstream optical path between the WEST station 17 and the authority 16, the authority 16 can communicate with the EAST station 18.
A communication path is secured between the stations 8 in the upward direction.

〔Effect of the invention〕

As explained above, according to one aspect of the present invention, received uplink and downlink optical signals of high order groups are converted into signals of low order groups, and desired low order group signals are obtained from the converted low order group signals. In addition to each extraction, new low-order group signals corresponding to the frequency band of the extracted low-order group signals are respectively inserted, converted into high-order group optical signals, and transmitted respectively. This is because a configuration is adopted in which when an optical signal from one of the higher-order groups is no longer received, it is converted using a synchronization signal separated from the higher-order groups in the other direction.

Even if a failure occurs in either the upstream or downstream direction, the authorities can convert the inserted low-order group signal into a high-order group optical signal and send it out to the optical transmission line. The reliability of a line using an optical transmission line can be improved.

[Brief explanation of drawings]

Figure 1 is a block diagram of the principle of the present invention, and Figure 2 is a block diagram of the principle of the present invention.
Embodiment Configuration Diagram FIG. 3 shows a system configuration diagram of the present invention. In the figure, 1.4 is OR (optical receiver), 2 is drop/insert control section, 3.5 is O3 (optical transmitter), 6-1.6
-2 is a fault detector, 7-1.7-2 is 5YNC (synchronization separation circuit), 8-1.8-2 is PC (pulse generator), 9
-1.9-2 is SW (switch), 10-1.10-2
is S/P (Serial to Parallel Converter), 11-1
．． 11-2 is SEL (selector), 12-1.12-
2 represents P/S (parallel/serial converter).

Claims (1)

[Claims] A high-order group optical signal multiplexed with a low-order group transmission signal is relayed in the upstream and downstream directions, and optionally any low-order group optical signal included in the high-order group optical signal is relayed. In the optical intermediate repeater configured to take in and take out the optical signals, the optical receivers (1) and (4) convert the received uplink and downlink optical signals of the higher order groups into electrical signals, respectively.
), and respective synchronization separation circuits (7) for separating synchronization signals from the received uplink and downlink optical signals of the respective higher-order groups.
-1) (7-2) and the synchronization signal separated by the synchronization separation circuit (7-1) (7-2) is converted into an electrical signal by the optical receiver (1) (4). Each serial-to-parallel converter (10
-1) (10-2) and the serial/parallel converter (10-1) (10-2)
selectors (11-1) and (11-2) for extracting a desired low-order group signal from the low-order group signal converted by and inserting the low-order group signal; and the synchronous separation circuit (7). -1) Each parallel-to-serial converter (
12-1) (12-2) and the parallel-serial converter (12-1) (12-2)
and optical transmitters (3) and (5) for converting the high-order group signals converted by , a switch unit (9-1) (9-2) that introduces the synchronization signal separated by the synchronization separation circuit (7-1) (7-2) from the optical signal of the higher order group in the other direction.
2), an optical intermediate repeater is characterized in that it is configured to transmit a higher-order optical signal by using a synchronization signal separated from an optical signal in the other direction.