WO1999059281A1 - Optical multiplexer and optical demultiplexer - Google Patents

Optical multiplexer and optical demultiplexer Download PDF

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Publication number
WO1999059281A1
WO1999059281A1 PCT/DE1999/001305 DE9901305W WO9959281A1 WO 1999059281 A1 WO1999059281 A1 WO 1999059281A1 DE 9901305 W DE9901305 W DE 9901305W WO 9959281 A1 WO9959281 A1 WO 9959281A1
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Prior art keywords
optical
band
filter
filters
transmission channels
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PCT/DE1999/001305
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German (de)
French (fr)
Inventor
Peter Krummrich
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Siemens Aktiengesellschaft
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Publication date
Application filed by Siemens Aktiengesellschaft filed Critical Siemens Aktiengesellschaft
Priority to AU47678/99A priority Critical patent/AU4767899A/en
Publication of WO1999059281A1 publication Critical patent/WO1999059281A1/en

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    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04J—MULTIPLEX COMMUNICATION
    • H04J14/00—Optical multiplex systems
    • H04J14/02—Wavelength-division multiplex systems

Definitions

  • Optical transmission systems are increasingly using the long-wavelength multiplex method, in which several channels with different wavelengths are transmitted over the same transmission path. At the beginning of the route, the individual channels must be brought together to form a transmission band, which is divided into individual channels again at the end of the route.
  • the channels are, for example, using a non-wavelength-selective power splitter fiber coupler
  • Demultiplexers that are implemented with 1: N couplers and filters also have high vapors.
  • the object of the invention is to provide optical multiplexers and demultiplexers with low vapors.
  • FIG. 1 shows an optical demultiplexer according to the invention
  • Figure 2 shows an optical multiplexer according to the invention.
  • the demultiplexer DMUX shown in FIG. 1 is designed as a filter cascade which has the structure of a binary tree. Each filter has one input and two outputs, each of which is connected to inputs of filters of the next filter stage. Accordingly, the number of filters doubles in each subsequent stage.
  • An input of the optical DE De ultiplexers DMUX or Fl of the first filter is a transmission band ⁇ - 8 supplied and ⁇ - in a lower sub-band 4 and an upper sub-band ⁇ 5-8 divided up.
  • a second filter FD2 divides the lower sub-band into two further sub-bands ⁇ lf2 and ⁇ 3 , 4 which are adjacent in terms of wavelength; Accordingly, the upper subband is divided in a third filter FD3 into likewise adjacent further adjacent subbands ⁇ 5 , 6 and ⁇ 7 , e.
  • the lower and upper sub-band are thus in each case again lower in another and another upper subband split
  • Wavelength filters can be used as filters, combining a high pass and. correspond to a low pass. It is of course also possible to use filters with bandpass characteristics in whole or in part in order to suppress interference outside the wavelength ranges used.
  • FIG. 2 shows an optical multiplexer MUX, which is also implemented as a filter cascade with the same tree structure. The filters each have two inputs ME1, ME2; ... and an output MA on. The first filter stage FM4 to FM7 is used to combine two adjacent transmission channels ⁇ i, ⁇ 2 ; ⁇ 3 , ⁇ 4 , ... to ⁇ 7 , ⁇ 6 .
  • the number of transmission channels usually corresponds to a power of 2.
  • the optical multiplexer or demultiplexer can of course also be implemented for any number of channels.
  • the filters used are known components, for example from E-TEK Dynamics, ENC. , 1855 Lundy Avenue, San Jose, CA 95131 USA.
  • Demultiplexers and multiplexers can be built modularly and expanded according to the number of transmission channels required. In the simplest case, only two channels, for example ⁇ i and ⁇ 5 , can be transmitted, for which purpose only the filters FM1 and FD1 are required. In a first ER can wide treatment stage with the aid of the filter and FM2 FM5 and FD2 and FD5 four channels, for example, ⁇ : ⁇ 3, ⁇ 5 and ⁇ are 7 / transfer, etc.

Abstract

Optical multiplexer (MUX) and optical demultiplexer (DMUX) with a cascade structure according to the principle of a binary tree. In the case of the demultiplexer, a transmission band (μ1-8), is split into a lower partial band (μ1-4) and an upper partial band (μ5-8) in a first optical filter (FD1). The partial bands are split into further partial bands (μ1,2...μ7,8) or into transmission channels (μ1-μ8). Individual transmission channels are grouped correspondingly in the multiplexer. Low insertion loss and gradual expandability provides additional advantages.

Description

1 Beschreibung 1 description
Optischer Multiplexer und optischer DemultiplexerOptical multiplexer and optical demultiplexer
Optische Ubertragungssysteme nutzen zunehmend das ellenlan- gen-Multiplexverfahren, bei dem mehrere Kanäle mit unterschiedlichen Wellenlangen über dieselbe Übertragungsstrecke übertragen werden. Am Anfang der Strecke m ssen die einzelnen Kanäle zu einem Ubertragungsband zusammengeführt werden, das am Ende der Strecke wieder in einzelne Kanäle aufgeteilt wird.Optical transmission systems are increasingly using the long-wavelength multiplex method, in which several channels with different wavelengths are transmitted over the same transmission path. At the beginning of the route, the individual channels must be brought together to form a transmission band, which is divided into individual channels again at the end of the route.
In bisher eingesetzten Wellenlangenmultiplex-Ubertragungs- systemen werden die Kanäle beispielsweise mit Hilfe eines nicht wellenlangenselektiven Leistungsteiler-FaserkopplersIn wavelength division multiplex transmission systems used to date, the channels are, for example, using a non-wavelength-selective power splitter fiber coupler
(Power Combiner) zusammengef hrt. Diese Komponente laßt sich zwar ohne Anpassung für eine Vielzahl von Wellenlangenkombi- nationen verwenden, ihr Hauptnachteil besteht jedoch m der hohen Emfugedampfung.(Power Combiner) merged. Although this component can be used for a large number of wavelength combinations without adaptation, its main disadvantage lies in the high level of vaporization.
Demultiplexer, die mit l:N-Kopplern und Filtern realisiert werden, weisen ebenfalls hohe Dampfungen auf.Demultiplexers that are implemented with 1: N couplers and filters also have high vapors.
Aufgabe der Erfindung ist es, optische Multiplexer und Demul- tiplexer mit geringen Dampfungen anzugeben.The object of the invention is to provide optical multiplexers and demultiplexers with low vapors.
Diese Aufgabe wird durch die unabhängigen Ansprüche gelost.This task is solved by the independent claims.
Der Vorteil dieser Losung liegt nicht nur m der geringen Emfugedampfung, der Multiplexer oder Demultiplexer kann auch entsprechend den Anforderungen stufenweise weiter ausgebaut werden.The advantage of this solution lies not only in the low level of vaporization, the multiplexer or demultiplexer can also be gradually expanded according to the requirements.
Vorteilhafte Weiterbildungen der Erfindung sind m den Un- teranspruchen angegeben. 2Advantageous developments of the invention are specified in the subclaims. 2
Im Folgenden werden Ausführungsbeispiele der Erfindung anhand von Figuren näher erläutert.Exemplary embodiments of the invention are explained in more detail below with reference to figures.
Es zeigen:Show it:
Figur 1 einen erfindungsgemäßen optischen Demultiplexer und1 shows an optical demultiplexer according to the invention and
Figur 2 einen erfindungsgemäßen optischen Multiplexer.Figure 2 shows an optical multiplexer according to the invention.
Der in Figur 1 dargestellte Demultiplexer DMUX ist als Filterkaskade ausgeführt, die die Struktur eines binären Baumes aufweist. Jedes Filter weist einen Eingang und zwei Ausgänge auf, die jeweils mit Eingängen von Filtern der nächsten Filterstufe verbunden sind. Entsprechend verdoppelt sich die An- zahl der Filter in jeder folgenden Stufe.The demultiplexer DMUX shown in FIG. 1 is designed as a filter cascade which has the structure of a binary tree. Each filter has one input and two outputs, each of which is connected to inputs of filters of the next filter stage. Accordingly, the number of filters doubles in each subsequent stage.
Einem Eingang DE des optischen De ultiplexers DMUX bzw. des ersten Filters Fl wird ein Übertragungsband λι-8 zugeführt und in ein unteres Teilband λι-4 und ein oberes Teilband λ5-8 auf- geteilt. In der nächsten Filterstufe wird durch ein zweites Filter FD2 das untere Teilband in zwei wellenlängenmäßig benachbarte weitere Teilbänder λlf2 und λ3,4 aufgeteilt; entsprechend wird das obere Teilband in einem dritten Filter FD3 in ebenfalls benachbarte weitere benachbarte Teilbänder λ5,6 und λ7,e aufgeteilt. Das untere und das obere Teilband werden also jeweils wieder in ein weiteres unteres und ein weiteres oberes Teilband aufgeteilt Jedes dieser weiteren Teilbänder wird in einer dritten und hier letzten Filterstufe durch Filter FD4 bis FD7 in jeweils zwei wellenlängenmäßig benachbarte Übertragungskanäle λi, λ2jbis λ7, λ8 aufgeteilt, die an den Ausgängen DA1 bis DA8 abgegeben werden.An input of the optical DE De ultiplexers DMUX or Fl of the first filter is a transmission band λι- 8 supplied and λι- in a lower sub-band 4 and an upper sub-band λ 5-8 divided up. In the next filter stage, a second filter FD2 divides the lower sub-band into two further sub-bands λ lf2 and λ 3 , 4 which are adjacent in terms of wavelength; Accordingly, the upper subband is divided in a third filter FD3 into likewise adjacent further adjacent subbands λ 5 , 6 and λ 7 , e. The lower and upper sub-band are thus in each case again lower in another and another upper subband split Each of these additional subbands .lambda..sub.i in a third and final here filter stage by filters FD4 to FD7 in two wavelength moderately adjacent transmission channels λ 2j to λ 7 , λ 8 , which are output at the outputs DA1 to DA8.
Als Filter können Wellenlängenweichen eingesetzt werden, die der Kombination eines Hochpasses und. eines Tiefpasses ent- sprechen. Selbstverständlich können auch ganz oder teilweise Filter mit Bandpaßcharakter verwendet werden, um Störungen außerhalb der genutzten Wellenlängenbereiche zu unterdrücken. In Figur 2 ist ein optischer Multiplexer MUX dargestellt, der ebenso als Filterkaskade mit der gleichen Baumstruktur realisiert ist. Die Filter weisen jeweils zwei Eingänge ME1, ME2; ... und einen Ausgang MA auf. Die erste Filterstufe FM4 bis FM7 dient zum Zusammenfassen von jeweils zwei benachbarten Übertragungskanälen λi, λ2; λ3, λ4, ... bis λ7, λ6.Wavelength filters can be used as filters, combining a high pass and. correspond to a low pass. It is of course also possible to use filters with bandpass characteristics in whole or in part in order to suppress interference outside the wavelength ranges used. FIG. 2 shows an optical multiplexer MUX, which is also implemented as a filter cascade with the same tree structure. The filters each have two inputs ME1, ME2; ... and an output MA on. The first filter stage FM4 to FM7 is used to combine two adjacent transmission channels λi, λ 2 ; λ 3 , λ 4 , ... to λ 7 , λ 6 .
Die jeweils am Ausgang eines dieser Filter abgegebenen weite- ren Teilbänder λ:, λ2 bis λ7, λ8 werden zu einem unteren Teilband λι-4 und einem oberen Teilband λ5-8 zusammengefasst in den Filtern FM2 und FM3 und in einem ersten Filter FM1 zum Übertragungsband λi-β kombiniert, das am Ausgang MA des Multiple- xers abgegeben wird.The output in each case at the output of this filter weite- ren subbands λ: λ 2 to λ 7, λ 8 are λι- to a lower sub-band 4 and an upper sub-band λ 5-8 summarized in the filters FM2 and FM3, and in a first Filter FM1 combined to the transmission band λi-β, which is delivered at the output MA of the multiple.
Die Anzahl der Übertragungskanäle entspricht meist einer Potenz von 2. Der optische Multiplexer bzw. Demultiplexer kann selbstverständlich auch für beliebige Kanalzahlen realisiert werden.The number of transmission channels usually corresponds to a power of 2. The optical multiplexer or demultiplexer can of course also be implemented for any number of channels.
Die verwendeten Filter sind bekannte Bauelemente, die beispielsweise von der Firma E-TEK Dynamics, ENC . , 1855 Lundy Avenue, San Jose, CA 95131 USA bezogen werden können.The filters used are known components, for example from E-TEK Dynamics, ENC. , 1855 Lundy Avenue, San Jose, CA 95131 USA.
Demultiplexer und Multiplexer können modular aufgebaut werden und entsprechend der Anzahl der benötigten Übertragungskanäle erweitert werden. So können im einfachsten Fall nur zwei Kanäle, beispielsweise λi und λ5 übertragen werden, wozu nur die Filter FM1 und FDl erforderlich sind. In einer ersten Er- weiterungsstufe können mit Hilfe der Filter FM2 und FM5 sowie FD2 und FD5 vier Kanäle, z.B. λ:, λ3, λ5 und λ7/ übertragen werden, usw. Demultiplexers and multiplexers can be built modularly and expanded according to the number of transmission channels required. In the simplest case, only two channels, for example λi and λ 5 , can be transmitted, for which purpose only the filters FM1 and FD1 are required. In a first ER can wide treatment stage with the aid of the filter and FM2 FM5 and FD2 and FD5 four channels, for example, λ: λ 3, λ 5 and λ are 7 / transfer, etc.

Claims

Patentansprüche claims
1. Optischer Wellenlängen-Demultiplexer (DMUX) zum Aufteilen eines Übertragungsbandes (λι-8) in Übertragungskanäle (λι-λ8) , dadurch gekennzeichnet, daß er als Filterkaskade mit optischen Filtern (FD1-FD7) ausgebildet ist, die jeweils einen Eingang und zwei Ausgänge ausweisen, daß ein erstes Filter (FDl) vorgesehen ist, durch das ein Übertragungsband (λι_8) in ein unteres Teilband (λ^) und ein oberes Teilband (λ5-8) aufgeteilt wird, und daß weitere Filter (FD2, FD3; FD4 - FD7 ) vorgesehen sind, durch die die Teilbänder (λlι2, λ5-8) in weitere obere und untere benachbarte Teilbänder (λlf2, λ3,4; λ5,6, λ7/8) oder in ein- zelne Übertragungskanäle (λi, λ2, λ3, ...λ8) aufgeteilt werden.1. Optical wavelength demultiplexer (DMUX) for dividing a transmission band (λι- 8 ) into transmission channels (λι-λ 8 ), characterized in that it is designed as a filter cascade with optical filters (FD1-FD7), each having an input and two outputs identify that a first filter (FDL) is provided, through which a transfer tape (λι_ 8) in a lower sub-band (λ ^) and an upper sub-band (λ 5-8) is divided, and in that further filters (FD2, FD3; FD4 - FD7) are provided, through which the subbands (λ lι2 , λ 5 - 8 ) into further upper and lower adjacent subbands (λ lf2 , λ 3 , 4 ; λ 5 , 6 , λ 7/8 ) or in individual transmission channels (λi, λ 2 , λ 3 , ... λ 8 ) can be divided.
2. Optischer Wellenlängen-Demultiplexer nach Anspruch 1, dadurch gekennzeichnet, daß 2N (N = 2 ,3,4,...) Ausgänge vorgesehen sind.2. Optical wavelength demultiplexer according to claim 1, characterized in that 2 N (N = 2, 3.4, ...) outputs are provided.
3. Optischer Wellenlängen-Demultiplexer nach Anspruch 1 oder Anspruch 2, dadurch gekennzeichnet, daß er modular aufgebaut und durch mindestens eine Filterstufe (FD4 - FD8) erweiterbar ist.3. Optical wavelength demultiplexer according to claim 1 or claim 2, characterized in that it is modular and expandable by at least one filter stage (FD4 - FD8).
4. Optischer Multiplexer (MUX) zum Zusammenfassen mehrerer Übertragungskanäle (λι~λ8) , dadurch gekennzeichnet, daß er als Filterkaskade mit optischen Filtern (FM1 - FM7 ) ausgebildet ist, die jeweils zwei Eingänge (ME1, ME2; ...) und einen Ausgang aufweisen, daß an den Eingängen der Eingangsfilter (FM4 - FM7) benach- barte Übertragungskanäle (λi, λ2; λ3, λ4; ...) anliegen, die zunächst zu weiteren benachbarten Teilbändern (λ:,2; λ3/4;...) zusammengefaßt werden, 5 daß weitere Filter (FM2, FM3; FMl) vorgesehen sind, durch die die weiteren benachbarten Teilbändern (λι,2; λ3/4;...) zu umfassenderen Teilbändern (λι- ; λ5_8) oder zu einem Übertragungsband (λi-β) zusammengefaßt werden.4. Optical multiplexer (MUX) for combining several transmission channels (λι ~ λ 8 ), characterized in that it is designed as a filter cascade with optical filters (FM1 - FM7), each with two inputs (ME1, ME2; ...) and having an output that at the inputs of the input filter (FM4 - FM7) neigh- bouring transmission channels (.lambda..sub.i, λ 2; λ 3, λ 4 ...) lie, the first λ to another adjacent sub-bands (:, 2; λ 3/4 ; ...) are summarized, 5 that further filters (FM2, FM3; FM1) are provided, through which the further adjacent subbands (λι, 2 ; λ 3/4 ; ...) to form more extensive subbands (λι-; λ 5 _ 8 ) or to a transmission band (λi-β) can be summarized.
5. Optischer Wellenlängen-Multiplexer nach Anspruch 4, dadurch gekennzeichnet, daß 2N (N= 2,3,4...) Eingänge vorgesehen sind.5. Optical wavelength multiplexer according to claim 4, characterized in that 2 N (N = 2,3,4 ...) inputs are provided.
6. Optischer Wellenlängen-Multiplexer nach Anspruch 4 oder Anspruch 5, dadurch gekennzeichnet, daß er modular aufgebaut und durch mindestens eine weitere Filterstufe (FM4-FM7) erweiterbar ist. 6. Optical wavelength multiplexer according to claim 4 or claim 5, characterized in that it has a modular structure and can be expanded by at least one further filter stage (FM4-FM7).
PCT/DE1999/001305 1998-05-12 1999-05-03 Optical multiplexer and optical demultiplexer WO1999059281A1 (en)

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US6353497B1 (en) 2000-03-03 2002-03-05 Optical Coating Laboratory, Inc. Integrated modular optical amplifier
US6389188B1 (en) 1999-02-23 2002-05-14 Optical Coating Laboratory, Inc. Hybrid wavelength selective optical router and switch
US6792210B1 (en) 1999-08-23 2004-09-14 Optical Coating Laboratory, Inc. Hybrid optical add/drop multiplexing devices
US6885824B1 (en) 2000-03-03 2005-04-26 Optical Coating Laboratory, Inc. Expandable optical array

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DE102005050739B4 (en) * 2005-10-22 2011-07-07 ESA Patentverwertungsagentur Sachsen-Anhalt GmbH, 39114 Demultiplexed polymer fiber transfer receiver and method of making the same

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Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6389188B1 (en) 1999-02-23 2002-05-14 Optical Coating Laboratory, Inc. Hybrid wavelength selective optical router and switch
US6792210B1 (en) 1999-08-23 2004-09-14 Optical Coating Laboratory, Inc. Hybrid optical add/drop multiplexing devices
US6353497B1 (en) 2000-03-03 2002-03-05 Optical Coating Laboratory, Inc. Integrated modular optical amplifier
US6885824B1 (en) 2000-03-03 2005-04-26 Optical Coating Laboratory, Inc. Expandable optical array

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