SOLUTION PATHS TO LIMIT INTERFEROMETRIC NOISE-INDUCED PERFORMANCE DEGRADATION IN ASK DIRECT DETECTION LIGHTWAVE NETWORKS/

Interferometric noise, arising on the optical interference of the desi red information signal and parasitic crosstalk waveforms at the photod etector, afflicts practically all lightwave communication networks, in ducing unacceptable power penalties and bit error rate floors. In this paper, the induced performance degradation is quantified, both experi mentally and analytically, and solution paths are identified. It is co ncluded that the total crosstalk level of noise generating parasitics in a generalized optical network must be held below -25 dB for a penal ty of less than 1 dB-a further 2 to 4 dB may lead to network failure; otherwise, means of suppressing the noise by RF rejection at the recei ver must be invoked. A number of approaches to achieving a reduction i n the level of interferometric noise are presented and contrasted.