WDM ring network using a centralized multiwavelength light source and add-drop multiplexing filters

Abstract

We propose and experimentally demonstrate a wavelength division multiplexed (WDM) ring network employing a centralized multiwavelength light source to supply all nodes with optical carriers of precise wavelength spacing. This approach overcomes the problem of monitoring and controlling the wavelengths of optical sources dispersed throughout the network. A four-node test bed using optical lattice-type add-drop multiplexing filters and a multiwavelength light source based on resonant cavity-enhanced four wave mixing in a Fabry-Perot laser diode was constructed to demonstrate the feasibility of the proposed method. The effects of coherent crosstalk in such networks are analyzed, and methods such as phase scrambling or the use of a pulsed optical source are shown to significantly reduce the effects of coherent crosstalk. The use of four-port add-drop multiplexer (ADM) filters instead of 1:n optical wavelength multiplexer/demultiplexers to implement the wavelength add-drop function at each node is shown to lead to a broader transmission bandwidth for each channel and also easier compatibility with the coherent crosstalk suppression mechanisms described.

A routing and wavelength assignment scheme supporting multiple light-source nodes in multi-carrier-distributed optical mesh networks with wavelength reuse

“…In the ring topology, an optical carrier connection, which connects the MCLS node and a requested lightpath, or between two requested lightpaths, is uniquely determined because the connecting direction is limited [11]. It is very simple to select the optical carrier connection since there are only two possible paths, the clockwise and anticlockwise directions.…”

“…In practical cases, all routes of optical carrier connections and requested lightpaths are required to be designed to minimize the number of wavelengths. The work in [5][6][7][8][9][10][11][12][13] provided only a wavelength assignment scheme. The routing of optical carrier connections and requested lightpaths was not considered.…”

A routing and wavelength assignment scheme in multi-carrier-distributed optical mesh networks with wavelength reuse

“…19 shows that the optimum MCLS node location in the European COST 239 network is nodes 1, 2, 3, 5, 7, and 8. Finally, in the U.S. long distance network, the optimum MCLS node location is nodes 1, 2, 3, 4, 5, 6,7,8,10,11,13,14,16,17, and 20, as depicted in Fig. 20.…”

“…In the ring topology, an optical carrier connection, which connects the MCLS node and a requested lightpath, or between two requested lightpaths, is uniquely determined because the connecting direction is limited [10]. It is very simple to select the optical carrier connection since there are only two possible paths, which are the clockwise and anticlockwise directions.…”

“…In practical cases, all routes of optical carrier connections and requested lightpaths are required to be designed to minimize the number of wavelengths. The work in [4][5][6][7][8][9][10][11][12] provided only a wavelength assignment scheme. The routing of optical carrier connections and requested lightpaths was not considered.…”