KR19990033783A - Wavelength Division Multiplexed Transmission Multichannel Wavelength Combiner - Google Patents

Abstract

The present invention provides a wavelength division multiplexing transmission method in which a wavelength division multiplexing transmission method for transmitting light of multiple wavelengths to one optical cable is capable of simply and easily branching and combining only desired wavelengths in each branch of multiple channels. Regarding a multi-channel wavelength branch coupling device,

The present invention provides a multi-channel wavelength branching apparatus of a wavelength division multiplexing transmission method, and circulates and branches a wavelength division multiplexed optical signal from a wavelength division multiplexing transmission apparatus, and reflects only a wavelength corresponding to a desired channel among the cycled optical signals. A first wavelength branching means for branching, combining and transmitting to the receiving end; and circulating and branching a multi-channel optical signal passed through without being reflected by the first wavelength branching means, reflecting a wavelength corresponding to a desired channel among the circulated optical signals, and selectively Multiplexing the second wavelength diverter means for branching and passing the signal to the receiving end, the multi-channel optical signal passed through without being reflected by the first and second wavelength diverter means, and the multi-channel inputted from another transmitter; After the multiplexed multi-channel is characterized by consisting of the coupling means for transmitting with the combined channel control the light intensity.

Description

Wavelength Division Multiplexed Transmission Multi-Channel Wavelength Divider

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a multi-channel wavelength splitting apparatus of a wavelength division multiplexing transmission method. Particularly, in a wavelength division multiplexing transmission method of transmitting light of several wavelengths to one optical cable, only a desired wavelength is selectively selected at each branch among several channels. The present invention relates to a multi-channel wavelength division combiner of a wavelength division multiplexed transmission system that can be easily divided and combined to transmit.

In general, Wavelength Division Multiplexing transmits multiple wavelengths of light from multiple input channels to one optical cable and outputs them to multiple outputs, or two from two or more input / output channels. Or, it is very effective to increase the transmission amount by transmitting light of more wavelengths through one optical cable in both directions and is being applied to ultra high speed communication.

As described above, in transmitting a plurality of channels in a wavelength division multiplexing transmission method, a multichannel branch coupling device for branching only a desired channel among multiple channels to be transmitted is used in each section. There is a device using an arrayed waveguide grating (AWG) device and an optical fiber grating. When the arrayed waveguide grating device is used, all channels are reversed even when only a small number of channels are to be branched. In order to demultiplex and multiplex all the channels, an additional device is required to match the wavelengths of the arrayed waveguide gratings. In order to attenuate each channel Since the insertion loss and the complexity of the overall configuration as well as the price of the arrayed waveguide grating itself are very high, especially when trying to branch-couple only several channels, there is a problem of high unit cost. Will have

Meanwhile, in the case of using the optical fiber grating, branch coupling is required by using two optical circulators for branch coupling of one channel, so that the unit cost increases due to the use of two optical circulators. In addition, there is a case in which a branch channel is affected, and each channel is fixed so that the dynamic selection function of the branch channel is insufficient.

An object of the present invention is to provide a wavelength branch combining apparatus capable of branching and combining transmission by simply and stably selectively branching only desired wavelengths among a plurality of channels transmitted in wavelength division multiplexed transmission.

In order to achieve the above object, the present invention provides an optical circulator for passing and circulating a wavelength division multiplexed multi-channel optical signal from a wavelength division multiplexing transmission device, and a desired channel of the multi-channel optical signal passed and circulated in the optical circulator. First and second optical fiber gratings reflecting only wavelengths within a desired bandwidth, an optical coupler for passing an optical signal reflected from the first and second optical fiber gratings, and an optical coupler of the optical signals passed through the optical coupler A first wavelength branching means comprising a third optical fiber grating for reflecting only the reflected optical signal to the optical coupler and separating it into two channels, and a channel passing through the first and second optical fiber gratings of the first wavelength branching means without being reflected Of the second optical circulator and the optical signal passing through the second optical circulator in the desired bandwidth A fourth optical fiber grating, an optical coupler for passing the optical signal reflected by the fourth optical fiber grating, and only an optical signal reflected by the fourth optical fiber grating among the optical signals passed by the optical coupler to the optical coupler to reflect the two channels. A 5X optical fiber grid for selectively passing a fifth optical fiber lattice separated by a light source, an optical signal passing through the fourth optical fiber grid without being reflected, and a sixth optical fiber grid for reflecting an optical signal passed through the 2x2 optical switch A second wavelength branching means, a first optical attenuator for adjusting the intensity of the remaining optical signal reflected from the second wavelength branching means, and N: 1 light for multiplexing multiple channels input from another transmitting device into a combined channel. A coupler, a second optical attenuator for controlling the light intensity of the coupling channel multiplexed in the N: 1 optical coupler, and an optical beam of the first and second optical attenuators It is characterized by consisting of a coupling means consisting of a 2: 1 optical coupler for transmitting the call together.

1 is a control block diagram of a multi-channel wavelength branch coupling device of the present invention;

* Explanation of symbols for main parts of the drawings

1,4; Optical circulators 2,2a, 3,5,5a, 6; Fiber optic grating

7; Optical switches 8, 9, 11, 11a; Optical coupler

10, 10a; Optical attenuator

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

1 is a control block diagram of a multi-channel wavelength splitting apparatus of the present invention, comprising: an optical circulator 1 having at least three ports for passing and circulating a wavelength division multiplexed optical signal input from a wavelength division multiplexing transmission apparatus; First and second optical fiber gratings 2 and 3 reflecting only wavelengths of a desired channel among optical signals passed and circulated in the optical circulator 1 within a desired bandwidth, and the first and second optical fiber gratings 2. The optical coupler 11 for passing the optical signal of the channel reflected by (3), and only the optical signal reflected by the first optical fiber grating 2 of the optical signals passed by the optical coupler 11 is again used for the optical coupler ( 11) a first wavelength branching means comprising a third optical fiber grating 2a which is connected to the receiving end and connected to the receiving end and passes the optical signal reflected by the second optical fiber grating 3 to separate the wavelength into two channels; First and second light of the first wavelength branching means The optical circulator 4 which passes and circulates the optical signal of the channel which has not been reflected by the flow gratings 2 and 3 as it is, and the desired bandwidth of only the wavelength of the channel for which the optical signal passed through the optical circulator 4 is desired. A fourth optical fiber grating 5 for reflecting inside, an optical coupler 11a for passing an optical signal reflected by the fourth optical fiber grating 5, and an optical signal passed through the optical coupler 11a. A fifth optical fiber grating 5a for separating optical channels of the reflected and non-reflected channels to 11 channels and separating them into two channels, and an optical signal that is not reflected from the fourth optical fiber grating 5 and passed through A second wavelength branching means composed of a 2x2 optical switch 7 for passing therethrough, a sixth optical fiber grating 6 for reflecting an optical signal passing through the 2x2 optical switch 7 selectively, and the second wavelength branching means To adjust the intensity of the multi-channel Is a first optical attenuator 10, an N: 1 optical coupler 9 for multiplexing multiple channels input from another transmitting device into a combined channel, and an optical signal multiplexed at the N: 1 optical combiner 9; A second optical attenuator 10a for adjusting the intensity, and a 2: 1 optical coupler for transmitting the multi-channel optical signals of which the intensity is adjusted in the first optical attenuator 10 and the second optical attenuator 10a together; It is composed of a coupling means consisting of 8).

The first wavelength branching means and the second wavelength branching means may be combined to increase to the Nth wavelength branching means, respectively, as necessary.

Referring to the operation of the present invention configured as described above are as follows.

When the multi-channel optical signal transmitted from the wavelength division multiplexing transmission device is input to the optical circulator 1 of the first wavelength branching means, the optical circulator 1 for passing and circulating the input multi-channel optical signal is used. The optical signal is transmitted to the first optical fiber grating 2 and the second optical fiber grating 3 which reflects only the wavelength of the desired channel of the optical signal within the desired bandwidth.

Accordingly, the first optical fiber grating 2 and the second optical fiber grating 3 reflect the wavelengths corresponding to the respective channels of the multi-channel optical signals transmitted from the optical circulator 1 and the optical circulator 1 Pass the optical coupler 11 to the third optical fiber grating 2a to transmit only the optical signal of the wavelength of the desired channel to the receiving end. In this case, the third optical fiber grating 2a passes through the optical coupler 11 Of the reflected optical signals transmitted to the third optical fiber grating 2a, only the optical signal of the channel reflected and transmitted from the first optical fiber grating 2 is reflected back to the optical coupler 11 so that the optical coupler 11 receives the receiving end. In addition, the optical signal reflected from the second optical fiber grating 3 passes through and separates the wavelengths and transmits them to the receiver.

In this way, in the state in which the wavelength of the desired channel among the multi-channel optical signals input by the first wavelength diverter means is diverted, the first and second optical fiber gratings 2 and 3 of the first wavelength diverter means The non-reflected optical signal, that is, the optical signal of the channel passed without being reflected, passes through the optical circulator 4 of the second wavelength branching means as it is, and the optical signal passed through the optical circulator 4 is the wavelength of the desired channel. Only the channel wavelength corresponding to the wavelength passed through the fourth optical fiber grating 5, the 2x2 optical switch 7, and the fifth optical fiber grating 6 reflecting only within the desired bandwidth is reflected. The optical signal passed in (5) is reflected or passed through the fifth optical fiber grating 6 according to the selection of the bar and the cross of the 2x2 optical switch 7.

Therefore, the optical signals reflected from the fourth optical fiber grid 5 and the fifth optical fiber grid 6 respectively pass through the optical circulator 4 and the optical coupler 11a to the sixth optical fiber grating 5a to the receiving end. Only the optical signal of the desired channel is transmitted separately. In this case, in the sixth optical fiber grating 5a, the fourth optical fiber grating 5 of the reflected optical signals transmitted to the sixth optical fiber grating 5a through the optical coupler 11a is transmitted. Reflects only the optical signal transmitted back to the optical coupler (11a) to connect the optical coupler (11a) to the receiving end and the optical signal reflected from the fifth optical fiber grating (6) to pass through the wavelength Is separated and transmitted to the receiving end.

On the other hand, the multi-channel optical signal passed through the second wavelength branch means without reflecting from the optical fiber gratings (2) (3) (4) (5) is again controlled by the first optical attenuator (10). Coupling and transmission to the optical coupler (8), wherein the optical coupler (8) multiplexes the multiple channels input from other transmitters into the coupling channel through the N: 1 optical coupler (9) and the multiplexed coupling channel In the first optical attenuator 10 and the second optical attenuator 10a, the optical attenuator 10a is transmitted to a coupling channel in which the intensity of light is adjusted to be the same size as the channel of the first optical attenuator 10. It will be able to transmit with the combined channel to be transmitted respectively.

As described above, in the present invention, a multi-channel branch coupling device for branching a desired channel in a wavelength division multiplexing system is composed of an optical cycler, an optical fiber grating, an optical switch, an optical attenuator, and an optical coupler. By reflecting only the desired wavelength within the bandwidth through the optical fiber grating, the reflected optical signal is branched to the optical circulator and used as a channel, and the optical signal not reflected by the optical fiber grating is selectively branched through the optical switch and transmitted to the optical coupler. Multi-channel can be easily and easily branched and transmitted, and the optical signal passed through the optical attenuator controls the intensity of light with the combined channel to be transmitted to the optical coupler, thereby diverging the channel by the combined channel during optical coupling. It will provide the effect that can be transmitted without affecting .

Claims (5)

In a multi-channel wavelength branching apparatus of a wavelength division multiplexing transmission method, a wavelength division multiplexed optical signal is circulated and branched from a wavelength division multiplexed transmission apparatus, and only the wavelength corresponding to a desired channel is reflected, branched, and combined A first wavelength branching means for transmitting to a receiving end and a multi-channel optical signal passed through without being reflected by the first wavelength branching means, and reflecting and selectively branching and passing a wavelength corresponding to a desired channel among the circulated optical signals The second wavelength diverter means for transmitting to the receiving end, the multi-channel optical signal passed through without being reflected by the first and second wavelength diverter means, and the multiple channels inputted from other transmitters, and then multiplexed. Wavelength division multiplexing, characterized in that it consists of coupling means for transmitting together with a combined channel of controlling the light intensity of the multi-channel The branch wavelength channels coupled device of the transmission system. The optical circulator 1 having the three or more ports for passing and circulating the inputted wavelength division multiplexed optical signal, and the light passed and circulated in the optical circulator 1 The light passing through the first and second optical fiber gratings 2 and 3 reflecting only the wavelength of a desired channel within the desired bandwidth within the desired bandwidth and the optical signal reflected from the first and second optical fiber gratings 2 and 3. Only the optical signal reflected by the first optical fiber grating 2 of the optical signal passed by the optical coupler 11 and the optical coupler 11 is reflected back to the optical combiner 11 to be transmitted to the receiving end and the second signal. An optical signal grating reflected from the optical fiber grating (3) is composed of a third optical fiber grating (2a) for separating the wavelength into two channels through the multi-channel wavelength branch coupling device of the wavelength division multiplexing transmission method. 2. The optical circulator 4 according to claim 1, wherein the optical circulator 4 passes and circulates the optical signal of the channel which is passed without being reflected by the first and second optical fiber gratings 2 and 3 of the first wavelength branching means. A fourth optical fiber grating 5 for reflecting the optical signal passing through the optical circulator 4 only within a desired bandwidth and an optical coupler 11a for passing the optical signal reflected from the fourth optical fiber grating 5; ), A fifth optical fiber grating 5a for separating the optical signal passed through the optical coupler 11a into two channels by passing the optical signal reflected and not reflected to the optical coupler 11a, and the fourth optical fiber. A 2x2 optical switch 7 for switching and passing the optical signal of a channel that is not reflected by the grating 5 and a sixth optical fiber grating for reflecting the optical signal selectively passing through the 2x2 optical switch 7 6) wavelength division multiplexing characterized in that consisting of The transmission method of the branch channel connecting apparatus. The method of claim 1, wherein the coupling means comprises: a first optical attenuator 10 for adjusting the intensity of the remaining optical signal reflected from the second wavelength branching means, and N for multiplexing multiple channels input from another transmitting device; A first optical coupler 9, a second optical attenuator 10a for adjusting the intensity of light multiplexed in the N: 1 optical coupler 9, the first optical attenuator 10 and the second optical attenuator 10a. A multi-channel branch coupling device of a wavelength division multiplexing transmission method comprising a 2: 1 optical combiner (8) for transmitting an optical signal of a channel whose intensity is adjusted and a coupling channel together. 5. The optical attenuator of claim 4, wherein the coupling means comprises: a first optical attenuator in which the intensity of the light of the channel passed through the first and second wavelength diverters without reflecting from the optical fiber grids (2) (3) (4) (5). The combined channel multiplexed through the N: 1 optical combiner 9, which is controlled by the multiplexer 10 and multiplexes the multiple channels input from the other transmitting device, is connected to the first optical attenuator 10 through the second optical attenuator 10a. Wavelength-division multiplexed transmission, characterized in that it is configured to be transmitted together with the channel transmitted to the first optical attenuator 10 through the optical combiner 8 after the intensity of the optical signal is adjusted to be the same size as the channel. Multi-channel branch coupling device.