JPS62112429A - Duplicated optical loop network - Google Patents

Abstract

PURPOSE:To constitute right and left both systems by one optical fiber by using a light multiplexer/demultiplexer and light sources of plural wavelengths so as to assign a different wavelength light to the right rotary system and the left rotatary system thereby constituting the duplicated optical loop. CONSTITUTION:An optical signal of wavelength lambda1 is sent in the right rotatary system and an optical signal of a wavelength lambda2 is sent in the left rotary system. The transmission signal of the right rotatary system is led to the light multiplexer/demultiplexer 9 by an optical fiber 8, reproduced into an electric signal by a photoelectric transducer 12 and branched. The branched signal is converted into an optical signal of wavelength lambda1 by an electrooptic transducer 12 together with an insertion signal of the own station and sent to an optical fiber 8' by the light multiplexer/demultiplexer 10. The transmission signal of the left rotary system is led to the light multiplexer/demultiplexer 10 through the fiber 8' after the reproduced into an electric signal by a photoelectric transducer 14 simularly and branched. The branched signal is sent to the optical fiber 8 via an electrooptic converter 11 and the light multiplexer/demultiplexer 9. If a transmission line with the next station of the right rotatary system is failed, the branching signal of the right rotatary system is switched by a changeover switch 15 and sent as the signal of the left rotatary system.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Field of Application) The present invention provides a method for making telephone calls and telephone calls using a loop-shaped optical transmission line within an area.
The present invention relates to an optical loop network used in an optical LAN for communication such as FAX and TV.

(Configuration of conventional example and its problems) FIG. 2 shows an optical-to-electrical converter at one station of a conventional dual optical loop network.

The configuration of this conventional example will be explained below with reference to FIG. 2.

In Figure 2, 1 and 1' are clockwise optical fibers, 2
, 2' are left-handed optical fibers, 3 and 6 are optical to electrical converters, 4 and 5 are electrical to optical converters, and 7 is a changeover switch for loop return.

Next, the above conventional example will be explained.

In Fig. 2, a clockwise signal is guided by an optical fiber 1, and after being regenerated into an electrical signal by an optical-to-electrical converter 3, the signal is branched and inserted into an electrical-to-optical converter 4. The signal is transmitted from the electro-optical converter 4 to the next station through the optical fiber 1' along with the insertion signal.

Similarly, for counterclockwise signals, the signal on the optical fiber 2 is regenerated into an electrical signal by the optical/electrical converter 6, and then the signal is branched and inserted into the electrical/optical converter 5, together with the insertion signal of the own station. The signal is transmitted from the electro-optical converter 5 to the next station via the optical fiber 2'.

In addition, in the event of a failure such as a break in the transmission line between the clockwise system and the next station, the clockwise optical signal is converted into an electrical signal by the optical-to-electrical converter 3, and then the branch signal is sent to the changeover switch. 7, the signal is converted into an optical signal together with the insertion signal by the counterclockwise electrical/optical converter 3, and transmitted to the counterclockwise circuit via the optical fiber 2.

In this way, by switching the transmission line from one transmission line to the other using two loop-shaped optical fibers, both the right and left systems can be looped back at stations on both sides of the failure point. , the spread of failures can be minimized.

However, in the above conventional example, since independent optical fibers are used for both the right and left systems, there is a drawback that an optical fiber having a length twice the loop length must be used.

(Object of the invention) The present invention eliminates the above-mentioned drawbacks of the conventional technology, and aims to eliminate the above-mentioned drawbacks of the conventional optical fiber system.
- The purpose is to configure both the left and right systems of the workpiece using a single optical fiber.

(Structure of the Invention) In order to achieve the above-mentioned L1 objective, the present invention uses an optical multiplexer/demultiplexer and a light source of a plurality of waves R to obtain 9 wavelengths that become 11 in a 6-same number j system and a counterclockwise system. It constitutes a split Y/R double optical loop, and has the advantage of being able to configure both the left and right systems with one single C fiber.

(Example) An example of the present invention will be described below with reference to the drawings.

FIG. 1 is a diagram showing an optical-to-electrical converter according to an embodiment of the present invention, where 8 and 8' are optical fibers, and 9 is a wavelength λ1.
is an input, wavelength λ is a bidirectional optical multiplexer/demultiplexer with 7 being an output, lO
is the wavelength λ, is the input two wavelengths λ, is the output bidirectional optical multiplexer/demultiplexer, 11 is the wavelength λ, 13 is the electrical/optical converter that converts the wavelength λ2, and 12 and 11i are the optical/electrical converters, respectively. It is a converter.

Next, the operation of the above embodiment will be explained.

In FIG. 1, the clockwise transmission signal is an optical signal with a wavelength λ1, and the counterclockwise transmission signal is an optical signal with a wavelength λ.

The clockwise transmission signal is guided through an optical fiber 8 to an optical multiplexer/demultiplexer 9, where it is coupled to an optical/41-air converter 12, where it is regenerated into an electrical signal and then branched.

The branch signal is an electric signal along with the insertion signal of the self-controller.
The optical converter 13 converts the signal into an optical signal of wavelength λ1, and the optical multiplexer/demultiplexer 10 sends it to the optical fiber 8'.

The counterclockwise transmission signal is similarly guided to an optical multiplexer/demultiplexer 10 through an optical fiber 8', and is coupled to an optical/electrical converter 14 by the optical multiplexer/demultiplexer 10 (7, where it is regenerated into an electrical signal and then branched. .

The branch signal is converted into an optical signal of wavelength λ2 by the electric/optical converter 11 together with the add signal of the own station.

The optical multiplexer/demultiplexer sends out the light to the optical fiber 8.

Furthermore, in the event of a failure such as a break in the transmission line between the next station in the clockwise system, the optical signals λ, □ in the clockwise system will pass through the optical multiplexer/demultiplexer 9 and be sent to the optical/electrical converter 12. After converting it into an electrical signal, the branch signal is converted into an optical signal λ2 by the changeover switch 15 to the electric-to-optical converter 11 of the left turn j system, along with the insertion signal of the own station, and then passes through the optical multiplexer/demultiplexer 9). It is sent to the fiber-saving fiber 8 as a counterclockwise (+'li) signal.

In this embodiment, since both the left and right systems can be configured with one original fiber, there is no need to use two optical fibers to configure both the left and right systems as in the conventional example. have

(Effects of the Invention) The present invention has a double structure and provides the effects shown in Section 11 below.

(a) Since a duplex system is constructed with a single optical fiber, the optical fiber that is twice the length of the loop is required, whereas the optical fiber that is twice the length of the loop is It has the advantage of requiring only fiber.

(b) Since it uses an optical multiplexer/demultiplexer, it has the advantage of being able to transmit multiple different types of signals (for example, an analog signal and a digital signal in the clockwise direction, and another analog signal and a digital signal in the counterclockwise direction). I like it.

(c) Since an optical multiplexer/demultiplexer is used instead of an optical branch/coupler, it is compared to the case where an optical branch/coupler is used.
This has the advantage of providing a gain of 3d13 of the theoretical insertion loss of an optical branching coupler.

[Brief explanation of drawings]

FIG. 1 is a diagram showing an optical-to-electrical converter according to an embodiment of the present invention, and FIG. 2 is a diagram showing an optical-to-electrical converter at one station of a conventional dual optical loop network. 1, P, 2.2', 8.8'...Optical fiber 3,
6.12,14...Optical/electrical converter. 4, 5.11.13...Electrical/optical converter, 7.15
...Selector switch. 9.10... Optical multiplexer/demultiplexer. Patent applicant: Matsushita Electric Industrial Co., Ltd. Figure 1 9.10...9 liquid separators I+, +3...Tuntrap/yt, friend h 12.14...Fan I track Mongolia 15...・(1st hard)

Claims (1)

[Claims] Using an optical multiplexer/demultiplexer and a light source with multiple wavelengths, one wavelength is used for the clockwise system and the other wavelength is used for the counterclockwise system, creating a duplex system with a single optical fiber. A double optical loop network characterized by: