KR950009420B1 - Organization method of optical ring communication network - Google Patents

Abstract

The optical address processor is adopted to construct ultra-high speed optical ring network. An optical address processor (10) comprising an optical fiber delay line matched filter and a threshold detector, a gate pulse generator(1) and an optical switch, is set on intermediate nodes. The first and the second output terminals of the optical switch(6) are connected to an output optical fiber coupler(4b) and receiver of nodes respectively, and output terminals of the coupler are connected to the next node.

Description

How to configure optical ring communication network

1 is a block diagram of a typical optical ring network.

2 is a conventional optical packet switch.

3 is a block diagram of a conventional optical ring communication network.

4 is a block diagram of an all-optical packet switch.

5 is a block diagram of an optical ring communication network according to the present invention.

6 is a block diagram of a multi-channel optical ring communication network according to the present invention.

* Explanation of symbols for main parts of the drawings

1: gate pulse generator 2: optical fiber time delay line

3: fiber optic 4a: fiber optic separator

4b: optical fiber coupler 5: polarization regulator

6: Optical switch 6a: Optical switch input terminal

6b: first output terminal of the optical switch 6c: second output terminal of the optical switch

6d: Control signal input terminal of optical switch 7: Optical receiver

8: address processor 9: switch driver

10: optical address processor 11: semiconductor optical amplifier

12 wavelength multiplexer 13 wavelength separator

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical ring communication network, and more particularly, to the design of an all-optical ring communication network using an all-photonic packet switching device and a design of a multi-channel all-optical ring communication network in which wavelength multiplexing is applied to the ring communication network. will be.

Ring networks are widely used for local area networks (LANs), customer premise networks (CPNs), and so on. Source nodes are destinations before payloads (user data). A node (address) field is attached to form a cell or packet and transmitted through a ring cable. When receiving the cell at an intermediate node other than the receiving station, the cell is inputted to the station via the ring cable since the destination address of the cell does not match the station address.

When the receiving station receives this cell, since the cell's destination address matches the station address, it detects that the cell's destination is the station and receives the cell data into the receiving memory through the receiver of the station.

1 is a general ring network configuration diagram.

Optical ring communication network is composed of optical fiber (optical fiber) for large-capacity, ultra-fast transmission and reception. In such an optical ring communication network, conventionally, an optical ring communication network has been designed using an optical packet switch using an electrical address processor that uses an electrical signal to determine whether a cell destination address matches a station address.

2 is a block diagram of an optical packet switch using a conventional electrical address processor.

In the conventional system, when a cell of an optical signal is input to a receiving station through the optical fiber cable 3, about 10% of the optical signal is separated by the optical fiber separator 4a and input to the high speed optical receiver 7. It is done.

The optical receiver 7 detects an optical signal which is an address field of an input cell and converts the destination address optical signal into an electrical signal. The address of the electric signal thus converted is compared with the address of the station and the address of the cell by using an internal shift register with the address bits input to the address processor 8, and if the address of the station and the address of the cell match, If the control signal is '1', and if it does not match, the digital control signal '0' is provided to the optical switch driving circuit 9.

At this time, the optical switch driving circuit 9 controls the optical switch 6 in accordance with a control signal provided from the address processor 8. The optical switch 6 receives a digital control signal from the optical switch drive circuit 9 through the control signal input terminal 6d. When the optical switch 6 receives the control signal '0', the input terminal 6a of the optical switch 6 is received. The optical signal cell inputted to the first output terminal 6b and the control signal '1' when receiving the optical signal cell is switched to the second output terminal 6c.

Therefore, in the design of the conventional optical ring communication network, as shown in FIG. 3, the first output terminal 6b of the optical switch 6 is connected to the input of the output optical fiber combiner 4b together with the optical fiber connected to the transmitter of the station. The output of this coupler 4b is directed to the ring, and the second output terminal 6c is connected to the receiver of the station to form an optical ring communication network.

If any station in such an optical ring network wishes to transmit data to another station, the station is operating as a receiving station or there is no signal to relay to the next station, i.e. a signal to the ring cable exiting the station. Sends data when there is no

However, in this conventional method, since address processing for determining whether an address coincides at each station is made of an electric signal, there is a limitation of the speed of the communication network due to the speed of the electric signal in the communication network, making it difficult to realize an ultra-high speed optical communication network. Many.

The present invention aims to compensate for this drawback, and to design an ultra-high speed optical ring communication network by introducing an optical packet switch using an optical address processor.

4 is a block diagram of an all-optical packet exchanger employed in the present invention.

When the cell of the optical signal is input to the optical fiber cable to the receiving station, about 10% of the optical signal is separated by the optical fiber separator 4a and amplified while passing through the semiconductor optical amplifier 11 and input to the optical address processor 10. It is done.

Although not shown in the figure, the optical address processor 10 is composed of an optical fiber delay line matched filter and a threshold detector. The optical signal cell input to the optical address processor 10 is first input to the matching filter with the optical fiber delay line. The fiber-optic delay line matching filter has the address information of the station by inserting a dielectric reflective mirror or an optical fiber delay path and sends correlation pulses between the station information and the input optical address signal to the threshold detector. give.

At this time, since the autocorelation value is always larger than the crosscorrelation value, it is easily determined by the threshold detector whether the optical address signal of the input cell matches the address of the station.

In other words, if the optical address of the input cell matches the address of the station, the fiber-optic delay line matching filter uses autocorrelation pulses and, if they do not match, corsscorrelation pulses to the threshold detector, respectively. In this case, the threshold detector drives the gate pulse generator 1 with the digital control signal '1' if the value of the input correlation pulse is greater than the threshold value, and with the digital control signal '0' if the value is smaller than the threshold value.

At this time, the gate pulse generator 1 controls the optical switch 6 in accordance with a control signal provided from the optical address processor 10. When the value of the control signal input to 6d of FIG. 4 is '0', the optical switch 6 converts the cell of the optical signal input to the input terminal 6a of the optical switch to the first output terminal 6b. When the value of the control signal provided from the address processor 1 is '1', the cells are switched to the second output terminal 6c, respectively.

In the present invention, an all-optical ring communication network as shown in FIG. 5 is constructed by using an all-optical packet switch (FIG. 4) as described above.

That is, the first output terminal 6b of the optical switch 6 is connected to the input of the output fiber coupler 4b together with the optical fiber from the transmitter of the station, and the output of this coupler 4b is directed to the ring, The second output terminal 6c of the switch 6 is connected to the receiver of the station to form an optical ring communication network.

In addition, it is possible to increase the communication capacity of the communication network by using a wavelength multiplexing scheme for the all-optical ring communication network. The multi-channel all-optical ring communication network is configured as shown in FIG.

In the multi-channel all-optical ring communication network, a wavelength separator 13 is provided at an input terminal of each station to separate an optical signal input to each station for each wavelength and input to the all-optical packet exchanger 14, respectively. The second output terminals 6c in the all-optical packet exchanger 14 of each station are connected to the receiver of the station, and the first output terminals 6b of the optical switch 6 together with the optical fiber connected to the transmitter of the station are output fiber. A multi-channel all-optical ring network is combined to combine at the combiner 4b and multiplexed at the wavelength multiplexer 12 at the output of the station to the ring.

Therefore, the optical ring communication network of the present invention uses an all-optical packet exchanger that determines whether an address matches at an optical speed, thereby eliminating the need to convert an optical signal of a cell into an electrical signal at each station of the ring communication network, thereby reducing the speed of the electrical signal. By overcoming the limitations of the speed of the optical ring communication network, a high speed optical communication network is realized.

In addition, the wavelength multiplexing method is applied to the all-optical ring communication network to form a multi-channel all-optical ring communication network to realize a large capacity of the communication network.

Claims (2)

In a method of constructing an optical ring communication network in which a plurality of stations are annularly connected by an optical fiber cable, an optical address processor (10), a gate pulse generator (1), and an optical switch (6) comprising an optical fiber delay line filter and a threshold detector. An all-optical packet exchanger including the optical fiber switch in each of the stations, and the first output terminal 6b of the optical switch 6 of each station to the input of the output optical fiber combiner 4b together with the optical fiber connected to the transmitter of the station. And connecting the second output terminal (6c) with the receiver of each station, and connecting the output of the output fiber coupler (4b) with the next station. 2. The method of claim 1, wherein a wavelength separator (13) is configured at an input terminal of each station and a wavelength multiplexer (12) is configured at an output terminal for wavelength multiplexing.