Dual-wavelength source based optical circuit switching and wavelength reconfiguration in multi-hop ROADM systems

Using a dual-wavelength source, a single optical signal is distributed over two wavelengths. This approach is used to reduce power excursions due to optical circuit switching in ROADM systems. In a multi-hop optical transmission system with 100Gbps PM-QPSK signals switched over five ROADMs and 265 km of single mode fiber (SMF), power excursions are kept within ± 0.2 dB using dual-wavelength sources. A cumulative distribution function (CDF) of channel power excursions is generated from measurements of over 100 random channel loadings for four different channel loading plans. Using dual-wavelength sources, power excursions of up to ± 6 dB are reduced below ± 1.5 dB for 99% and ± 0.5 dB for 71.4% of the cases while switching up to 30 channels.