PERFORMANCE DEGRADATION OF MULTIWAVELENGTH OPTICAL NETWORKS DUE TO LASER AND (DE)MULTIPLEXER MISALIGNMENTS

In this letter, we use computer simulation techniques to evaluate the performance degradation for a multiwavelength optical network with a cascade of 30 randomly misaligned (de)multiplesers. Two types of (de)multiplexers are used in the simulation and modeled as third-order and first-order Butterworth filters, both with a full width half maximum (FWHM) of 125 GHz. For WDM systems at 10 Gb/s per optical channel with 30 uniformly misaligned filters, laser misalignment tolerances (at 0.3 dB distortion-induced-eye-closure penalty) vary from +/-30 GHz (+/-0.24 nm) for systems using third-order Butterworth filters to +/-20 GHz (+/-16 nm) for systems using first-order filters.