KR970008302B1 - Apparatus for add/drop of optic signal - Google Patents

Apparatus for add/drop of optic signal Download PDF

Info

Publication number
KR970008302B1
KR970008302B1 KR1019940033165A KR19940033165A KR970008302B1 KR 970008302 B1 KR970008302 B1 KR 970008302B1 KR 1019940033165 A KR1019940033165 A KR 1019940033165A KR 19940033165 A KR19940033165 A KR 19940033165A KR 970008302 B1 KR970008302 B1 KR 970008302B1
Authority
KR
South Korea
Prior art keywords
optical
channel
signal
optical signal
wavelength
Prior art date
Application number
KR1019940033165A
Other languages
Korean (ko)
Other versions
KR960027598A (en
Inventor
주무정
박창수
류갑열
Original Assignee
양승택
재단법인한국전자통신연구소
조백제
한국전기통신공사
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 양승택, 재단법인한국전자통신연구소, 조백제, 한국전기통신공사 filed Critical 양승택
Priority to KR1019940033165A priority Critical patent/KR970008302B1/en
Publication of KR960027598A publication Critical patent/KR960027598A/en
Application granted granted Critical
Publication of KR970008302B1 publication Critical patent/KR970008302B1/en

Links

Classifications

    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
    • G02B6/24—Coupling light guides
    • G02B6/26—Optical coupling means
    • G02B6/28—Optical coupling means having data bus means, i.e. plural waveguides interconnected and providing an inherently bidirectional system by mixing and splitting signals
    • G02B6/293—Optical coupling means having data bus means, i.e. plural waveguides interconnected and providing an inherently bidirectional system by mixing and splitting signals with wavelength selective means
    • G02B6/29346—Optical coupling means having data bus means, i.e. plural waveguides interconnected and providing an inherently bidirectional system by mixing and splitting signals with wavelength selective means operating by wave or beam interference
    • G02B6/29358—Multiple beam interferometer external to a light guide, e.g. Fabry-Pérot, etalon, VIPA plate, OTDL plate, continuous interferometer, parallel plate resonator
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
    • G02B6/24—Coupling light guides
    • G02B6/26—Optical coupling means
    • G02B6/28—Optical coupling means having data bus means, i.e. plural waveguides interconnected and providing an inherently bidirectional system by mixing and splitting signals
    • G02B6/293—Optical coupling means having data bus means, i.e. plural waveguides interconnected and providing an inherently bidirectional system by mixing and splitting signals with wavelength selective means
    • G02B6/29346—Optical coupling means having data bus means, i.e. plural waveguides interconnected and providing an inherently bidirectional system by mixing and splitting signals with wavelength selective means operating by wave or beam interference
    • G02B6/29361—Interference filters, e.g. multilayer coatings, thin film filters, dichroic splitters or mirrors based on multilayers, WDM filters

Landscapes

  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Optics & Photonics (AREA)
  • Optical Communication System (AREA)
  • Optical Filters (AREA)

Abstract

Optical signal add/drop apparatus optically embodies an add/drop function, removes the necessity of a light-to-electricity or electricity-to-light conversion, and simplifies a system construction. The apparatus includes: a optical circulator(10) for circulating a signal only toward an I/O terminal adjacent to one direction; a first optical filter(21) which is connected to one terminal(B) of the circulator(10), permeates an optical signal of a predetermined wavelength band, and reflexes the remaining signals; and a second optical filter(22) which is connected to th other terminal(C) of the circulator(10), permeates an optical signal of a predetermined wavelength band, and reflexes the remaining signals.

Description

광신호 삽입/추출 장치Optical signal insertion / extraction device

제1도는 파장분할 다중전송방식에서 전송되는 채널과 파장과의 상관관계를 나타낸 신호 파형도,1 is a signal waveform diagram showing a correlation between a channel and a wavelength transmitted in a wavelength division multiplexing scheme;

제2도는 파장분할 다중전송장치에서 채널 삽입/추출기능을 나타내는 기능 설명도,2 is a functional explanatory diagram showing a channel insertion / extraction function in a wavelength division multiplexing device;

제3도는 본 발명에 따른 광신호 삽입/추출장치 구성도.3 is a block diagram of an optical signal insertion / extraction device according to the present invention.

* 도면의 주요부분에 대한 부호의 설명* Explanation of symbols for main parts of the drawings

10 : 광순환기(optical circulator)21,22 : 간섭계형 필터10: optical circulator 21, 22: interferometric filter

본 발명은 광신호 삽입/추출 장치에 관한 것으로, 특히 일정한 파장에 대해서는 선택적으로 투과시키고 나머지는 반사하는 간섭계형 광필터와 광순환기를 이용하여 광주파수 혹은 파장분할 다중방식으로 전송되는 광신호에서 임의의 채널을 추출/삽입하는 광신호 삽입/추출 장치에 관한 것이다.BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for inserting / extracting an optical signal, and in particular, in an optical signal transmitted by an optical frequency or wavelength division multiplexing method using an interferometer type optical filter and an optical circulator that selectively transmit a predetermined wavelength and reflect the rest. An optical signal insertion / extraction device for extracting / inserting a channel of the present invention.

하나의 광섬유(optical fiber)에 서로 다른 파장을 갖는 복수개의 광신호를 중첩하여 동시에 전송하는 파장 혹은 주파수 분할 다중화(wavelength or frequency division multiplexing, 이하 WDM)기술에서 전송되는 여러개의 신호중 임의의 신호를 삽입/추출(add/drop)하는 기능은 매우 중요하다.Insert one of several signals transmitted by wavelength or frequency division multiplexing (WDM) technology to simultaneously transmit a plurality of optical signals having different wavelengths on one optical fiber The ability to add / drop is very important.

일반적으로, N개의 채널(channel)을 갖는 WDM 전송장치는 n개의 서로 다른 파장의 빛을 사용한다. 즉, 제1도와 같이 1번 채널은 파장이 λ1 인 광신호로 전송되고, 2번 채널은 λ2로, ……, N번 채널은 파장이 λn인 광신호로 전송된다.In general, a WDM transmission apparatus having N channels uses light of n different wavelengths. That is, as shown in FIG. 1, channel 1 is transmitted as an optical signal having a wavelength of λ 1 , and channel 2 is λ 2 . … , Channel N is transmitted as an optical signal having a wavelength of λ n .

삽입/추출 기능은 이러한 WDM방식의 광전송 장치에서 파장이 λi 인 임의의 I번 채널을 추출하여 분리해 내고, 다른 신호를 비어있는 채널에 삽입하여 전송하는 기능을 말한다.The insertion / extraction function refers to a function of extracting and separating an arbitrary I channel having a wavelength of λ i from the WDM optical transmission device and inserting another signal into an empty channel for transmission.

제2도는 상기와 같이 삽입/추출 기능을 도식적으로 나타낸 것이다.2 schematically shows the insertion / extraction function as above.

파장 다중화된 N개의 채널이 삽입/추출기에 입력되면 이 신호중 파장 λi인 채널 I는 삽입/추출기의 추출단으로 출력되고 나머지 채널은 출력단을 통해 출력된다. 이때, 파장 λi인 채널 I가 제거된 광신호에 다른 채널 K를 삽입하려고 하면 삽입/추출기의 삽입단에 파장 λk인 채널 K를 입력함으로써 가능하다.When N wavelength multiplexed channels are input to the inserter / extractor, channel I having a wavelength λ i of the signal is outputted to the extraction stage of the inserter / extractor and the remaining channels are outputted through the output stage. At this time, if another channel K is to be inserted into the optical signal from which the channel I having the wavelength λ i is removed, it is possible by inputting the channel K having the wavelength λ k to the insertion end of the inserter / extractor.

단, 채널 K를 삽입하는 경우에 입력되는 원신호에서 채널 K에 해당하는 부분은 비어있어야 한다. 채널 K가 원래부터 비어있으면, 추출단에서 추출된 채널 I를 제외한 나머지 채널의 구성은 1,2,…,I-1,I+1,…,K-1,K+1,…,N-1,N과 같이 된다. 여기에 삽입단으로부터 입력되는 파장 λk인 채널 K를 삽입하면 1,2,…,I-1,I+1,…,K-1,K,K+1,…,N-1,N의 채널이 다중된 신호가 삽입/추출기의 출력단으로 출력된다.However, when the channel K is inserted, the portion corresponding to the channel K in the original signal input should be empty. If channel K is originally empty, the configuration of the remaining channels other than channel I extracted from the extraction stage is 1,2,... , I-1, I + 1,... , K-1, K + 1,... , N-1, N. If a channel K having a wavelength λ k inputted from the insertion end is inserted, 1,2,... , I-1, I + 1,... , K-1, K, K + 1,... Signals multiplexed by N-1, N channels are output to the output of the inserter / extractor.

또한, 추출한 채널 I의 빈자리에 다른 정보를 갖는 채널 I'을 대체하여 삽입하는 것도 가능하며, 이는 앞에서 설명한 삽입 기능에서 삽입/추출기의 삽입단에 입력되는 채널 K의 채널 파장을 λi에 맞춤으로써 가능하다.In addition, it is also possible to insert the channel I 'having other information in the empty position of the extracted channel I by inserting the channel wavelength of the channel K input to the insertion end of the inserter / extractor to λ i in the above-described insertion function. It is possible.

상기와 같은 기능을 전자적으로 수행하기 위해서는 복잡한 구조의 광/전(optical/electrical)와 전/광(electrical/optical)변환장치 및 부속 회로가 요구됨에 따라 구성이 복잡하고, 신호의 삽입에 광결합기가 사용되므로 분기/결합에 따른 손실이 발생한다는 문제점을 가지고 있다.In order to perform the above functions electronically, an optical / electrical and electrical / optical converter and an accessory circuit having a complicated structure are required, and the configuration is complicated. Has the problem that a loss occurs due to branching / coupling.

이에, 본 발명은 상기와 같은 문제점을 해결하기 위해 안출된 것으로, 삽입/추출 기능을 광학적으로 구현함으로써 광/전 및 전/광 변환의 필요성을 없애고 장치의 구성을 단순화시킨 광신호 삽입/추출 장치를 제공하는 것을 그 목적으로 한다.Accordingly, the present invention has been made to solve the above problems, the optical signal insertion / extraction device that eliminates the need of light / pre and pre / light conversion by simplifying the configuration of the device by optically implementing the insertion / extraction function To provide that purpose.

상기와 같은 목적을 달성하기 위하여 본 발명은, 한방향으로 인접한 입출력단자로만 신호를 순환시키는 광순환기, 상기 광순환기의 일측 입출력단(B)에 접속되어 일정 파장대역의 광신호만 투과시키고 나머지는 반사시키는 제1광필터, 및 상기 광순환기의 다른 일측 입출력단(C)에 접속되어 일정 파장대역의 광신호만 투과시키고 나머지는 반사시키는 제2광필터를 구비하는 것을 특징으로 한다.In order to achieve the above object, the present invention, the optical circulator for circulating the signal only to the adjacent input and output terminals in one direction, is connected to one input and output terminal (B) of the optical circulator to transmit only the optical signal of a predetermined wavelength band and the rest is reflected And a second optical filter connected to the other input / output terminal C of the optical circulator and transmitting only an optical signal having a predetermined wavelength band and reflecting the rest.

이하, 본 발명의 일실시예를 첨부된 도면을 참조하여 상세히 설명한다.Hereinafter, an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

제3도는 본 발명에 따른 광신호 삽입/추출 장치 구성을 나타낸 것으로, 광순환기(optical circulator)(10)와 간섭계형 필터(21,22)로 구성되어 있다.3 shows the configuration of an optical signal insertion / extraction apparatus according to the present invention, and is composed of an optical circulator 10 and interferometric filters 21 and 22.

광순환기(10)는 4개의 입출력단을 갖는데, 각 입출력단을 A,B,C,D라 할 때, A로 입력되는 광신호는 B로 출력되고, B로 입력되는 광신호는 C로 출력되며, C로 입력되는 광신호는 D로 출력되고, D로 입력되는 광신호는 A로 출력된다.The optical circulator 10 has four input / output terminals. When each input / output terminal is referred to as A, B, C, and D, the optical signal input to A is output to B, and the optical signal input to B is output to C. The optical signal input to C is output to D, and the optical signal input to D is output to A.

간섭계형 필터(21,22)는 유전체 다층박막(dielectric thin-film multi-layer)으로 구성되거나 파브리-페로(Pabry-Ferot) 공진기(resonator)형의 필터로서, 박막의 두께나 공진기의 간격에 의해 결정되는 좁은 파장대역의 빛만 투과시키고 나머지는 반사시킨다.The interferometric filter (21, 22) is composed of a dielectric thin-film multi-layer or a Fabry-Ferot resonator type filter, depending on the thickness of the thin film or the spacing of the resonators. It transmits only the light of the narrow wavelength band that is determined and reflects the rest.

먼저, 상기와 같은 구성을 갖는 광신호 삽입/추출 장치의 광신호 추출 기능을 설명하면 다음과 같다.First, the optical signal extraction function of the optical signal insertion / extraction device having the above configuration will be described.

파장 다중화된 N개의 채널이 광순환기(10)의 입출력단 A에 입력되면 이 신호는 B단으로 출력되며, 이 출력신호는 채널 1부터 채널 N까지의 입력되는 원신호이다.When the N multiplexed wavelength channels are inputted to the input / output terminal A of the optical circulator 10, this signal is output to the B stage, and this output signal is the original signal inputted from channel 1 to channel N.

광순환기의 B단에는 간섭계형 필터(21)가 부착되어 채널 I의 파장 λi에 맞추어져 있다. 이 간섭계형 필터(21)는 채널 I의 파장 λi만 투과시키고 나머지는 반사시키므로 채널 I는 필터(21)를 통과하여 외부로 출력되고 나머지 채널은 반사되어 광순환기(10)의 B단으로 되돌아간다. 이때 반사되어 되돌아가는 신호는 채널 I를 제외한 나머지 채널(1,2,…,I-1,I+1,…,N-1,N)이 된다.An interferometric filter 21 is attached to the B stage of the optical circulator so as to match the wavelength λ i of the channel I. Since the interferometric filter 21 transmits only the wavelength λ i of the channel I and reflects the rest, the channel I passes through the filter 21 and is output to the outside, and the remaining channels are reflected and returned to the B stage of the optical circulator 10. Goes. At this time, the reflected signal is returned to the remaining channels (1, 2, ..., I-1, I + 1, ..., N-1, N) except for the channel I.

상기와 같이 필터(21)에서 반사되어 광순환기(10)의 B단으로 입력된 광신호는 광순환기의 C단으로 출력된다. 따라서, 서로 다른 여러개의 파장으로 다중화된 신호에서 필터의 투과파장에 따라 임의의 신호를 추출해 내고 나머지는 다음단으로 전송하는 추출기능의 광학적 구현이 가능하다.As described above, the optical signal reflected by the filter 21 and input to the B stage of the optical circulator 10 is output to the C stage of the optical circulator. Therefore, it is possible to optically implement an extraction function that extracts an arbitrary signal according to the transmission wavelength of the filter from the signal multiplexed with different wavelengths and transmits the rest to the next stage.

한편, 상기와 같이 파장 λi인 채널 I가 제거되어 비어있는 광신호에 다른 정보를 가진 채널을 삽입하려면 광순환기(10)의 C단에 파장 λi' 인 채널 I'을 투과시키고 나머지는 반사하는 필터(22)를 부착함으로써 가능하다.Meanwhile, in order to insert the channel having different information into the empty optical signal by removing the channel I having the wavelength λ i as described above, the channel I 'having the wavelength λ i ' is transmitted through the C terminal of the optical circulator 10 and the rest is reflected. It is possible by attaching the filter 22 to make.

광순환기(10)의 C단으로 출력되는 신호는 앞서 B단에서 추출된 채널 I를 제외한 나머지 채널이며, 이는 채널 1,2,…,I-1,I+1,…,N-1,N으로 구성되어 있다. 이 신호는 C단에 부착된 필터(22)에서 반사되어 되돌아가고, 필터(22)를 통해 입력되는 파장 λi' 인 채널 I'와 합쳐진다. 즉, 1,2,…,l-1,I',I+1,…,N-1,N의 채널이 다중된 신호가 광순환기의 D단으로 출력된다. 따라서 필터의 투과 파장에 따라 임의의 신호를 삽입하여 다음단으로 전송하는 삽입기능의 광학적 구현이 가능하다. 이때 추출한 채널 I자리에 다른 정보를 갖는 채널 I'을 대체하여 삽입하는 것 뿐만 아니라 다른 파장의 채널 K를 부가하는 것도 가능하며, 이는 광순환기(10)의 C단에 접속하는 필터(22)의 투과 파장을 파장 λk에 맞추고 C단의 필터를 거쳐 입력된는 신호를 이 파장으로 전송함으로써 가능하다. 단, 이 경우 채널 K 자리가 비어 있어야 가능하다.The signal output to the C stage of the optical circulator 10 is a channel other than the channel I extracted from the B stage, and the channels 1,2,... , I-1, I + 1,... , N-1, N. This signal is reflected by the filter 22 attached to the C stage and returned, and is combined with the channel I 'having the wavelength λ i ' input through the filter 22. That is, 1,2,... , l-1, I ', I + 1,... A signal obtained by multiplexing the N-1, N channels is output to the D stage of the optical circulator. Therefore, it is possible to optically implement the insertion function of inserting an arbitrary signal according to the transmission wavelength of the filter and transmitting it to the next stage. In this case, not only the channel I 'having different information is inserted into the extracted channel I but also a channel K having a different wavelength can be added, which is used for the filter 22 connected to the C stage of the optical circulator 10. The transmission wavelength is adjusted to the wavelength [lambda] k , and the signal input through the C stage filter can be transmitted by this wavelength. In this case, however, channel K must be empty.

상기와 같이 본 발명은 파브리-페로 필터와 같은 파장가변 간섭계형 필터를 사용함으로써 삽입/추출하는 채널의 임의 변경이 용이할 뿐만 아니라 신호의 삽입에 광결합기(optical coupler)를 사용하지 않으므로 광순환기의 필터의 삽입손실 외에는 분기/결합에 의해 발생되는 손실이 없이 이를 사용하는 전송장치의 동작 여유도(margine)를 높여준다는 장점이 있다.As described above, the present invention facilitates arbitrary change of the channel to be inserted / extracted by using a wavelength variable interferometric filter such as a Fabry-Perot filter, and does not use an optical coupler to insert a signal. In addition to the insertion loss of the filter, there is an advantage that increases the operating margin of the transmission device using the same without loss caused by branching / coupling.

Claims (3)

한방향으로 인접한 입출력단자로만 신호를 순환시키는 광순환기(10); 상기 광순환기(10)의 일측 입출력단(B)에 접속되어 일정 파장대역의 광신호만 투과시키고 나머지는 반사시키는 제1광필터(21); 및 상기 광순환기(10)의 다른 일측 입출력단(C)에 접속되어 일정 파장대역의 광신호만 투과시키고 나머지는 반사시키는 제2광필터(22)를 구비하는 것을 특징으로 하는 광신호 삽입/추출 장치.An optical circulator 10 for circulating a signal only through adjacent input / output terminals in one direction; A first optical filter 21 connected to one input / output terminal B of the optical circulator 10 so as to transmit only an optical signal having a predetermined wavelength band and reflect the rest of the optical signal; And a second optical filter 22 connected to the other input / output terminal C of the optical circulator 10 so as to transmit only an optical signal having a predetermined wavelength band and reflect the rest of the optical signal. Device. 제1항에 있어서, 상기 광필터(21,22)유전체 다층박막(dielectric thin-film multi-layer)으로 구성된 것을 특징으로 하는 광신호 삽입/추출 장치.The optical signal insertion / extraction apparatus according to claim 1, wherein the optical filter (21, 22) is composed of a dielectric thin-film multi-layer. 제1항에 있어서, 상기 광필터(21,22)는 파브리-페로(Pabry-Ferot) 공진기(resonator)형의 필터인 것을 특징으로 하는 광신호 삽입/추출 장치.The optical signal insertion / extraction apparatus according to claim 1, wherein the optical filter (21, 22) is a Fabry-Ferot resonator type filter.
KR1019940033165A 1994-12-07 1994-12-07 Apparatus for add/drop of optic signal KR970008302B1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
KR1019940033165A KR970008302B1 (en) 1994-12-07 1994-12-07 Apparatus for add/drop of optic signal

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
KR1019940033165A KR970008302B1 (en) 1994-12-07 1994-12-07 Apparatus for add/drop of optic signal

Publications (2)

Publication Number Publication Date
KR960027598A KR960027598A (en) 1996-07-22
KR970008302B1 true KR970008302B1 (en) 1997-05-22

Family

ID=19400618

Family Applications (1)

Application Number Title Priority Date Filing Date
KR1019940033165A KR970008302B1 (en) 1994-12-07 1994-12-07 Apparatus for add/drop of optic signal

Country Status (1)

Country Link
KR (1) KR970008302B1 (en)

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR100478508B1 (en) * 2002-08-29 2005-03-28 한국전자통신연구원 An Optical Add/Drop Apparatus

Also Published As

Publication number Publication date
KR960027598A (en) 1996-07-22

Similar Documents

Publication Publication Date Title
JP2977024B2 (en) Optical circuit for wavelength division multiplexing communication and optical transmission communication system including the same
US5909295A (en) Hybrid bi-directional wavelength division multiplexing device
EP0887963A3 (en) Cascaded optical multiplexing devices
KR960008352A (en) Optics
JPH0983495A (en) Optical adm device
KR100207602B1 (en) Optical filter for preventing loss of optical power and optical demultiplexer using same
US6788899B2 (en) Dynamic wavelength add/drop multiplexer for UDWDM optical communication system
US6201907B1 (en) Optical drop circuit having group delay compensation
JPH07183872A (en) Optical bandpass filter
JPH07281042A (en) Optical-channel adding/falling filter
KR20020044310A (en) Bidirectional Optical Add/Drop Multiplexer
KR0183945B1 (en) Optical demultiplexer
KR970008302B1 (en) Apparatus for add/drop of optic signal
CA2235050A1 (en) Wavelength dividing circuit with arrayed-waveguide grating monitor port
US6782156B2 (en) Interleaved band demultiplexing/multiplexing system
US7167650B2 (en) Method and apparatus for demultiplexing high bit rate optical signals on dense wavelength grid
US7418168B2 (en) Optical add/drop module
JP3308148B2 (en) Optical submarine cable branching device for WDM communication system and WDM optical submarine cable network using the same
JPH11163791A (en) Optical branching device
EP1096713A2 (en) Optical add/drop multiplexer
JPS63287125A (en) Wavelength multiplex bidirectional transmission method
KR100687043B1 (en) Reconfiguable Optical Add Drop Multiplexer
KR100585319B1 (en) Optical multi-channel dynamic add and drop apparatus
JP2976613B2 (en) Optical circuit
JPH0750212B2 (en) WDM device

Legal Events

Date Code Title Description
A201 Request for examination
G160 Decision to publish patent application
E701 Decision to grant or registration of patent right
GRNT Written decision to grant
FPAY Annual fee payment

Payment date: 20030901

Year of fee payment: 7

LAPS Lapse due to unpaid annual fee