JPH04294660A - Optical subscriber equipment monitor system - Google Patents

Abstract

PURPOSE:To monitor the operation of an optical burst transmission section of a standby system as well as the operation of an optical burst reception section of the standby system. CONSTITUTION:AND circuits 41, 42 receive an output burst signal of a burst signal generating section 7 at their one input. A switching signal generating section 6 and an inverter 5 give the switching signal to the other input of the AND circuits 41, 42 for its pause period synchronously with an output burst signal of the burst signal generating section 7. The AND circuits 41, 42 give a burst signal to two optical burst signal transmission sections 11, 12 based on the switching signal.

Description

[Detailed description of the invention]

0001

FIELD OF INDUSTRIAL APPLICATION The present invention is applied to an optical subscriber equipment monitoring system for optical communications. In particular, the present invention relates to a passive double-star type optical subscriber equipment monitoring system that has a redundant system and uses time-compression multiplexing (TCM).

0002

2. Description of the Related Art FIG. 2 is a block diagram of a conventional optical subscriber equipment monitoring system.

Conventionally, a passive double-star type optical subscriber equipment monitoring system using a time-base compression multiplexing transmission system (TCM) having a redundant system has been proposed as shown in FIG. Burst signal receiving sections 21, 2
2, directional couplers 31, 32, and AND circuit 41
, 42, an inverter 5, a burst signal generator 7, and a switching signal generator 6 are installed in the station. In addition, the station is connected to the optical branching connector 8 via the optical subscriber lines 111 , 112 , and after branching is connected to a plurality of optical subscriber premises equipment 91 - 93 via the optical subscriber lines 211 - 213 . Ru.

An optical burst signal transmitting section 11 , an optical burst signal receiving section 21 , and a directional coupler 31 constitute a working system, and an optical burst signal transmitting section 12 , an optical burst signal receiving section 22 , and a directional coupler 32 constitute a backup system. Configure the system. The burst signal generator 7 outputs the output burst signal to the AND circuit 4.
1, 42. The output signal of the AND circuit 42 is inputted by the output signal of the switching signal generator 6, and only the AND circuit 41 is input to the optical burst signal transmitter 11.
Outputs a burst signal to. Here, the optical burst signal transmitting sections 11 and 12 do not output an optical burst signal when the input burst signal is at the "L" level.

On the other hand, the backup optical burst signal transmitter 12
Since the AND circuit 42 inhibits the burst signal by the output signal of the switching signal generator 6 and does not transmit the optical burst signal, the optical burst signal transmitter 1 of the working system
Collision with the optical burst signal of 1 can be prevented. The standby system operates under the control of the switching signal generator 6 when a failure occurs in the active system.

[0006]

[Problems to be Solved by the Invention] However, in such a conventional optical subscriber equipment monitoring system, the optical burst signal receiving section of the backup system receives optical burst signals from the optical subscriber premises equipment as well as the active system. Since the signal is input via the optical branch connector, operation monitoring is possible.However, the standby optical burst signal transmitter is connected to the optical subscriber line between the optical branch connector and the optical subscriber premises equipment. Since it is a book, it is not possible to monitor the operation because the optical burst signal is not output to avoid collision with the optical burst signal of the active system, and there is a problem that failure detection is only possible after switching to the backup system. .

[0007] The present invention solves the above problems.
It is an object of the present invention to provide an optical subscriber equipment monitoring system capable of monitoring the operation of not only a backup optical burst signal receiving section but also a backup optical burst signal transmitting section.

[0008]

[Means for Solving the Problems] The present invention provides a working system and a system for transmitting optical burst signals to a plurality of optical subscriber premises equipment respectively via directional couplers and optical branching connectors based on input burst signals. Two standby optical burst signal transmitters, a burst signal generator that generates a burst signal, and switching to switch the output burst signal of the burst signal generator and give it to one of the two optical signal burst transmitters. In the optical subscriber equipment monitoring system, the switching means includes means for switching and applying the output burst signal of the burst signal generating section to a rest period of the burst signal.

Further, in the present invention, the switching means has two logical products, one input of which is connected to the output of the burst signal generation section, and the output of which is connected to the input of the two optical burst signal transmission sections, respectively. and switching signal generating means for alternately applying a switching signal to the other input of the two AND circuits in synchronization with the output burst signal of the burst signal generating section.

Further, in the present invention, the optical branching connector is inserted between the directional coupler and the plurality of optical subscriber premises equipment, and each of them is connected via one optical subscriber line. Can be done.

[0011]

[Operation] The switching means switches the output burst signal of the burst signal generating section during the rest period of the burst signal and supplies it to one of the two optical signal generating sections.

As described above, it is possible to monitor the operation of not only the backup optical burst signal receiving section but also the backup optical burst signal transmitting section.

[0013]

Embodiments Examples of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram of an optical subscriber equipment monitoring system according to an embodiment of the present invention.

In FIG. 1, the optical subscriber equipment monitoring system is as follows:
Two optical systems, a working system and a standby system, transmit optical burst signals based on the input burst signals to a plurality of optical subscriber premises equipment 91 to 93 via the directional couplers 31 and 32 and the optical branch/connector 8, respectively. Burst signal transmitters 11 and 12, a burst signal generator 7 that generates burst signals, and two optical signal burst transmitters 11 that switch the output burst signals of the burst signal generator 7.
, 12.

A feature of the present invention is that the switching means includes means for switching and applying the output burst signal of the burst signal generating section 7 during the rest period of the burst signal.

The switching means also includes two AND circuits 41, one input of which is connected to the output of the burst signal generator 7, and the output of which is connected to the inputs of the two optical burst signal transmitters 11 and 12, respectively. , 42 and a switching signal generating section 6 and an inverter 5 as switching signal generating means for alternately applying switching signals to the other inputs of the two AND circuits 41, 42 in synchronization with the output burst signal of the burst signal generating section 7. including. Further, the optical branching connector 8 is inserted between the directional couplers 31, 32 and the plurality of optical subscriber premises equipments 91-93, and connects them via one optical subscriber line 111, 112, 211-213, respectively. Connected.

The operation of the optical subscriber equipment monitoring system having such a configuration will be explained.

In FIG. 1, the optical subscriber equipment monitoring system is as follows:
Since it is a TCM system, optical signals to be transmitted are not generated continuously but in bursts. The burst signal generator 7 outputs the burst signal to the AND circuits 41 and 42. The AND circuits 41 , 42 select the optical burst signal transmitters 11 , 12 based on the output signal of the switching signal generator 6 .

[0019] Here, the optical burst signal transmitter 11,
12 does not output an optical burst signal when the input burst signal is at the "L" level. The switching signal generating section 6 is synchronized with the burst signal generating section 7, and the optical burst signal transmitting section 11, 12 is synchronized with the burst signal generating section 7.
Switch. Therefore, in order to operate the optical burst signal transmitting section 11 and the optical burst signal transmitting section 12 alternately without generating an error in the burst signal, it is possible to monitor the operation even if one of them is in a failure state. Note that if one of the optical burst signal transmitters is in a failure state, the switching signal generator 6 fixes the burst signal path to the normal optical burst signal transmitter 1.

[0020]

As described above, the present invention has the excellent effect of being able to monitor the operation of not only the backup optical burst signal receiving section but also the backup optical reception burst signal transmitting section.

[Brief explanation of drawings]

FIG. 1 is a block diagram of an optical subscriber equipment monitoring system according to an embodiment of the present invention.

FIG. 2 is a block diagram of a conventional optical subscriber equipment monitoring system.

[Explanation of symbols]

11, 12 Optical burst signal transmitter 21, 22
Optical burst signal receivers 31, 32 Directional couplers 41, 42 AND circuit 5 Inverter 6 Switching signal generator 7 Burst signal generator 8 Optical branch connectors 91 to 93 Optical subscriber premises equipment

Claims (3)

[Claims] Claim 1: Two optical burst signals for a working system and a protection system, each of which transmits an optical burst signal to a plurality of optical subscriber premises equipment via a directional coupler and an optical branch/connector, respectively, based on an input burst signal. An optical subscriber comprising a transmitting section, a burst signal generating section that generates a burst signal, and switching means for switching the output burst signal of the burst signal generating section and applying it to one of the two optical signal burst transmitting sections. An optical subscriber equipment monitoring system, characterized in that the switching means includes means for switching the output burst signal of the burst signal generating section to an idle period of the burst signal. 2. The switching means comprises two AND circuits each having one input connected to the output of the burst signal generating section and the output connected to the input of the two optical burst signal transmitting sections, respectively; 2. The optical subscriber equipment monitoring system according to claim 1, further comprising switching signal generating means for alternately applying a switching signal to the other input of the two AND circuits in synchronization with the output burst signal of the burst signal generator. 3. The optical branching connector according to claim 1, wherein the optical branching connector is inserted between the directional coupler and the plurality of optical subscriber premises equipment, and each is connected via one optical subscriber line. Optical subscriber equipment monitoring method.