12.5GHz-100GHz tunable spacing optical carrier source for flexgrid bandwidth variable transponders

A flexible optical carrier source for bandwidth variable transponders (BV-Ts) managing a variable number of carriers at continuously variable free spectral range (FSR) up to 100 GHz is experimentally demonstrated. The photonic radio frequency (RF) synthesis allows achieving larger carrier spacing and simplified tuning without need of multiple RF clock sources. The cost and complexity of the scheme is independent of carrier spacing.