DE102005051290A1 - Add-drop device for wavelength multiplexed signals - Google Patents

Abstract

The invention relates to a wavelength-selective switch to which a WDM signal is fed. A split filter (Split1) is connected upstream of the wavelength-selective switch (WSS) on the input side, which extracts at least one partial signal of the WDM signal and feeds the remaining partial signals to the wavelength-selective switch (WSS).

Description

The The present invention relates to add-drop devices for wavelength division multiplexed signals, respectively WDM signals, according to the preamble of claims 1 and Third

For transmission Data is increasingly being used by optical networks. These transmit with optical signals or optical wavelength division multiplexed signals, in short WDM signals, such data or information. A WDM signal consists of several optical (sub) signals that are wavelength division multiplexed be summarized to a WDM signal. An optical (partial) Signal transmits thereby a set of data from a source to a destination. The the optical Signals associated frequency or wavelength ranges are also called channels designated. That in an (optical) channel becomes an optical signal or (partial) signal transmitted. The sum of the transmitted through the channels Signals form the WDM signal.

The Optical networks consist of different network elements passing through Fiber optic cables are connected together. Such network elements are For example, add-drop devices or add-drop multiplexer. These serve on the one hand, from an optical wavelength multiplex signal / WDM Signal a (partial) signal to branch off respectively to "droop" and on the other hand to insert a signal or sub-signal in the WDM signal respectively add ( "Add").

An add-drop multiplexer for optical signals is disclosed in the patent US 6,590,681 B1 presented.

One optical network at the wavelengths for both distribution as well as for selective switching is used in the publication US 2002/0067523 A1.

One Comparison of different cross-connect architectures for optical Paths or optical networks is described in the "Journal of Lightwave Technology" Vol. 14, No. 10, October 1996, discussed.

One optical transmission device, an optical transmission system and an optical terminal station are in the American patent application US 2002/0101633 A1.

The heart of many Add drop facilities for WDM Signals is a wavelength-selective Switch. This is switchable so that the (sub-) signals one at its entrance WDM signals can be selectively output at its outputs / connections. That one or several (partial) signals of the WDM signal depending on the switching state delivered at any output of the switch. In reverse Working method can so several (sub-) signals are combined to a WDM signal. This will be the connections as inputs used.

The wavelength selective Switches are currently still relatively expensive and have only a limited Number of connections (Inputs and outputs) on.

task It is the object of the present invention to provide an add-drop device for WDM signals which has a wavelength-selective Switch has to improve.

These Task is performed by an add-drop facility with the features of Claim 1 or 3 solved.

According to the invention is proposed the wavelength-selective Switch on the input side a split filter upstream, with the at least a sub-signal of the WDM signal or a group of sub-signals, i.e. decoupling a so-called (frequency or wavelength) band. The remaining signals are supplied to the wavelength-selective switch. alternative or in addition becomes wavelength selective Switch a wavelength-selective Combiner followed, which inversely at least one more Signal or a group of (sub) signals or a (frequency or wavelengths) Tape adds to the WDM signal or coupled.

Of the Advantage of the invention is that signals or channels not the wavelength-selective switch supplied be processed and otherwise processed. Thus remain connections or Ports of the wavelength-selective Switch usable for others for other (sub-) signals, since the wavelength-selective switch only a limited number of connections having. Thus, part of the channels of the WDM signal is through the wavelength-selective switch freely switchable and another part is rigidly coupled in and out or otherwise interconnected.

advantageous Embodiments of the invention are in the dependent claims and in the embodiment specified.

In an advantageous embodiment of the invention, the split filter, a wavelength-selective demultiplexer is connected downstream of each of the decoupled partial signals at its output emits. This has the advantage that a (partial) signal is directly decoupled and is available for further use.

One embodiment The invention will be described in more detail below with reference to the drawing.

It shows:

1 an inventive add-drop device.

1 shows an add-drop device or an add-drop multiplexer for wavelength division multiplex signals or WDM signals, comprising a wavelength-selective switch WSS. An input WDM signal WDM1 is fed to a split filter Split1, which decouples at least one sub-signal of the WDM signal or a group of sub-signals, ie a so-called (frequency or wavelength) band or a number of channels, and feeds it to a wavelength-selective demultiplexer Demux1, which in each case emits one of the decoupled partial signals at its output. This means that one (sub-) signal or one channel is available at an output of the demultiplexer Demux1.

The remaining signals or channels become wavelength selective Switch (WSS) supplies. This branches off signals / drop and / or inserts new signals / add and / or conducts signals. This is through ports Add1, Add2, Drop1, Drop2 indicated. Such modified by the wavelength selective switch WDM signal is output side of a wavelength-selective Combiner Comb1 supplied the at least one further signal or group of (sub) Signals / channels or on (frequency or wavelength) Tape adds to the WDM signal or coupled and outputs a WDM signal WDM2 at its output.

the wavelength selective Combiner Comb1 can be a wavelength-selective Upstream of a multiplexer, which is a set of WDM-enabled signals combiner feeds Comb1 so that this group or this band of signals / channels is added to the WDM signal WDM2 to be output.

The Split filters can executed as a band filter each comprising a band comprising at least one signal Channel or a number of channels, at a first output and the remaining channels at one second output. The split filters can also be used as interleavers, Splitter or optical coupler be realized.

Of the wavelength selective Switch WSS can be as two or three dimensional wavelength selective Switch executed be.

Claims (4)

Add-drop device for wavelength-multiplexed signals, or WDM signals, comprising a wavelength-selective switch (WSS) to which the WDM signal is supplied, characterized in that the wavelength-selective switch (WSS) upstream of a split filter (Split1) upstream, the at least one sub-signal of the WDM signal decouples and supplies the remaining sub-signals to the wavelength-selective switch (WSS). Device according to claim 1, characterized that the split filter (Split1) is a wavelength-selective demultiplexer (DEMUX1) is connected, each one of the decoupled partial signals at its output. Add-drop device for wavelength multiplexed signals, respectively WDM signals, comprising a wavelength-selective switch (WSS), which outputs a WDM signal at its output, characterized, that the wavelength-selective Switch (WSS) a wavelength-selective Combiner (Comb1) is connected, which is at least one more Signal adds to the WDM signal. Device according to one of the preceding claims, characterized characterized in that the wavelength-selective Switch as two or three dimensional wavelength-selective switch are executed.