JPS61164395A - Optical exchange - Google Patents

Abstract

PURPOSE:To constitute an economical optical exchange network using an optical cable without provision of a signal private line other than information communication lines by transmitting branched light from a light branching means of a light reception section to a control means. CONSTITUTION:An incoming side cable 10 transmits an optical signal multiplexing plural wavelengths of a communication wave including communication information and a signal wave including control signal information. A light reception section 20 is provided with a light branching means 21 separating a signal wave transferred to a control circuit 40 from a received multiplexed optical signal from the optical cable 10 and a light reception means 22 for converting and processing the separated communication wave, and transfers the light of the communication wave transferred up to the incoming terminal device to light switch 30 and the light of the signal wave controlling the light switch 30 to the control circuit 40 after being subjected to signal conversion processing. The control circuit 40 receives a signal including incoming destination information from the light reception section 20, selects an outgoing optical cable 50 connected to the incoming destination to control the light switch 30 so as to be connected to an incoming line of the light reception section 20 having an outgoing call.

Description

[Detailed description of the invention] (Industrial application field) The present invention relates to an optical switch.

(Prior art) Conventional optical switching equipment takes advantage of the ability of light to transmit a large amount of information, and either transmits the signals used for switch control by including them in the optical signal, or transmits only the control signals separately from the information transfer line. Transmission is using a common line. Here, exchanges using optical switches adopt the latter, that is, the common line signaling method, converting only the light on the signal line into electrical signals and inputting them to the control circuit to control the optical switch, and the output side is also an electrical signal. The control signal is converted into an optical signal and sent to the signal line.

Therefore, since the optical switch handles only communication information, the peripheral circuits of the optical switch can be simplified.

(Problems to be Solved by the Invention) As mentioned above, conventional optical switching equipment is configured so that the line for control signals (information) is a separate line from the line for communication information. The characteristics of the optical cable, which is a line, are not utilized, and the optical cable within the communication network cannot be used effectively.

(Means for Solving the Problems) The optical exchanger of the present invention extracts demultiplexed light of a wavelength containing an exchange control signal from an optical signal input via an incoming optical cable, and passes optical signals of other wavelengths. an optical branching means for passing the light; an optical receiving means for processing the demultiplexed light and extracting a switching control signal; an optical switching means for transmitting the passing light from the optical branching means to an output optical cable; It is characterized by comprising a control means for selectively controlling the switch means in accordance with the exchange control signal inputted from the light receiving means.

(Example) Next, the present invention will be explained with reference to the drawings.

Referring to FIG. 1, which shows an embodiment of the present invention, an incoming optical cable 10 transmits an optical signal in which a plurality of wavelengths of a communication wave containing communication information and a signal wave containing control signal information are multiplexed. The optical receiver 20 receives the multiplexed optical signal via the incoming optical cable 10 connected to it, and sends the light of the communication wave to be transferred to the receiving terminal to the source switch 30, and the light of the signal wave to control the optical switch 30. The signal is converted and transferred to the control circuit 4o. The optical switch 30 connects one of the incoming optical cables 10 to at least one of the selected outgoing optical cables 50 under the control of the control circuit 40 . The control circuit 40 is the optical receiver 20
When receiving a signal including destination information from a destination, the optical switch 30 is controlled to select the outgoing optical cable 5o connected to the destination and connect it to the incoming line of the optical receiver 20 from which the call was made. Therefore, the optical receiver 20 includes a sufficient wave means 21 for separating a signal wave to be transferred to the control circuit 40 from a multiplexed optical signal including a plurality of wavelengths received via the optical cable 10, and a control circuit for receiving the separated signal wave. The optical receiver 22 converts the signal into a 4o processed signal format.

Next, FIG. 2 is a block diagram showing an example in which a transmitting terminal 60 and a receiving terminal 70 of broadband composite terminal equipment are connected to the optical exchange shown in FIG. 1. In FIG. In FIG. 2, components that are the same as those shown in FIG. 1 are given the same reference numerals and their explanations will be omitted. The transmitting terminal 60 sends out to the optical cable 10 an optical signal in which a signal wave of wavelength 8 and a communication wave of wavelength λC are multiplexed. The wavelength λC includes communication information between the originating terminal 60 and the destination terminal 70, while the wavelength λB includes information on the destination terminal 70 and control information for controlling the optical switch 30. The optical receiving section 20 of the optical exchange demultiplexes the wavelength λ8 from the optical signal received from the optical cable 10, and sends it to the control circuit 40.
At the same time, the remaining wavelength λC is sent to the optical switch 3.
Send to 0. Therefore, the optical communication information included in the wavelength λC is transmitted to the receiving terminal 70 via the optical cable 50 by the connection of the optical switch 30. The demultiplexed signal wave may be subjected to signal conversion processing by the optical branching means 20 as shown in FIG. 1, but the control circuit 40 may also directly receive and process the light of wavelength λ8.

FIG. 3 shows an example in which a two-stage optical switch is used, and the same components as those shown in FIGS. 1 and 2 are given the same reference numerals and their explanations will be omitted. In FIG. 3, the originating terminal 8
0 sends out two wavelengths λ8 and λ(2) as signal waves, and the signal to the first optical exchange includes information specifying the second optical exchange.The first optical exchange , the control circuit 4o selects the optical cable line to the second optical exchange and connects it to the optical switch 30.The second optical exchange has an optical receiving section 20'. The control circuit 40' splits and takes in the signal wave of the wavelength λ(), and the control circuit 40' switches the optical switch 30' under the control of the signal included in the wavelength λi.
is connected to the optical cable line to the receiving terminal 7o. Therefore, it is necessary for the originating terminal 8° to specify the route by including connection route information in the signal wave.

In the examples shown in Figures 2 and 3, the calling terminal sends a control signal to the control circuit of the optical switch using a signal wave of a specified wavelength during communication with the called terminal, and puts the call in progress on hold. You can receive services such as calling a third party and communicating with the third party, or making a three-party call including the third party.

FIG. 4 is a block diagram showing another embodiment of the optical exchange according to the present invention. In FIG. 4, components K that are the same as those shown in FIG. 1 are given the same reference numerals and their explanations will be omitted. The control circuit 4o'' receives a control signal from the optical receiving means 22 of the optical receiving section 20, controls the optical switch 30, and sends the control signal to the subsequent destination terminal or optical exchange.

The control signals include, for example, selection signals for the optical switch on the terminating side, while confirmation signals for example for the originating terminal on the originating side. The optical transmitter 90 is connected to the optical switch 30 and includes an optical multiplexer 91 and an optical transmitter 92. The optical multiplexing means 91 receives the optical signal transferred via the optical switch 30 and the optical signal of the control signal sent from the control circuit 40'', multiplexes it, and sends it to the output optical cable 50. Optical transmission The means 92 converts the control signal sent from the control circuit 40'' and transmits it to the optical multiplexing means 91 as an optical signal. Therefore, the terminal devices and optical exchanges at both ends of one optical cable, or the optical exchanges themselves, monitor the status of the optical cable and the status of the connected destination, determine whether or not light can be transmitted and received, and include a monitoring signal in the control signal to notify the user. It can be sent and received along with other communication information via two optical cables.

In the above embodiment, only one-way communication was explained using one optical cable, but bi-directional communication in up and down directions is also possible by using different wavelengths. A detailed explanation of signal processing has been omitted, but digital transmission by turning on and off light at low speeds does not require special optical-to-electrical conversion means, and for signals with a large amount of information, optical may be converted into an electrical signal. Furthermore, when multiplexing signals onto an optical cable for transmission, increasing the output by the signal wave can avoid a drop in output due to sufficient waves in the optical exchange.

(Effects of the Invention) As explained above, according to the present invention, one optical cable that multiplexes light of a predetermined wavelength containing a control signal required by a control means with light of other information as a signal wave and transmits the light By connecting to an optical switch via a receiving section and sending the demultiplexed light by the optical demultiplexing means of the optical receiving section to the control means, it is possible to use an optical cable without providing a dedicated signal line separate from the information communication line. In addition to being able to construct an economical optical switching network, 1. Since the relaying optical switch directly connects the incoming optical cable and the outgoing optical cable to transmit the optical signal, the optical signal can be transmitted from the originating station to the terminating station over a single line.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing an embodiment of an optical switch according to the present invention, FIG. 2 is a diagram showing an example in which a calling terminal and a receiving terminal are connected to the optical switch shown in FIG. 1, and FIG. 3 is a diagram showing an optical switch. FIG. 4 is a configuration diagram showing another embodiment of the present invention. 10.50...Optical cable, 20,20'...
. . . Optical receiving section, 21 . . . Optical demultiplexing means, 22
・・・・・・Optical receiving means, 30.30' ・・・・・・
Light switch, 40.40'. 40" ...control circuit. 1 Figure yr; zrm q Figure 3, Figure 4

Claims (1)

[Scope of Claims] Optical demultiplexing means for extracting demultiplexed light of a wavelength including an exchange control signal from an optical signal inputted through an input optical cable and passing optical signals of other wavelengths as passing light; an optical receiving means for processing the wave light and extracting a switching control signal; an optical switching means for transmitting the passing light from the optical demultiplexing means to an output optical cable; An optical exchanger comprising: control means for selectively controlling according to the exchange control signal;