Performance implications of component crosstalk in transparent lightwave networks

We find both theoretically and experimentally that crosstalk due to small component imperfections in transparent lightwave networks will tend to generate large performance degradations. The most severe degradations, which arise from interference between signal and crosstalk electric fields, are far larger than those predicted from simple power-addition without field interference. Systems corrupted by crosstalk from a single source of optical-field leakage appear to require component crosstalk levels /spl epsiv//spl les/-20 dB, if conventional receivers are used. Since the degradations are believed to depend on N/spl radic//spl epsiv/, where N is the number of crosstalk generators, each producing a crosstalk power level of /spl epsiv/, the problem is expected to grow rapidly severe with network size.<>