WDM RING NETWORK USING A CENTRALIZED MULTIWAVELENGTH LIGHT-SOURCE ANDADD-DROP MULTIPLEXING FILTERS

We propose and experimentally demonstrate a wavelength division multip lexed (WDM) ring network employing a centralized multiwavelength light source to supply all nodes with optical carriers of precise wavelengt h spacing, This approach overcomes the problem of monitoring and contr olling the wavelengths of optical sources dispersed throughout;the net work, A four-node test bed using optical lattice-type add-drop multipl exing filters and a multiwavelength light source based on resonant cav ity-enhanced four wave mixing in a Fabry-Perot laser diode was constru cted to demonstrate the feasibility of the proposed method, The effect s of coherent crosstalk in such networks are analyzed, and methods suc h 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 wa velength multiplexer/demultiplexers to implement the wavelength add-dr op function at each node is shown to lead to a broader transmission ba ndwidth for each channel and also easier compatibility with the cohere nt crosstalk suppression mechanisms described.