Fast Wavelength Switching Transceiver for a Virtualized Coherent Optical Network

Fast reconfigurable digital coherent transceivers will become a key subsystem in future virtualized optical networks as they provide the ability to tailor the channel frequency, symbol rate, and modulation format. This transceiver agility is of paramount importance for network resilience, bandwidth on demand applications, and congestion aware routing. We demonstrate a fast wavelength switching coherent transceiver based on semiconductor tunable lasers and a parallelized digital signal processing implementation. The inherent frequency and phase noise associated with semiconductor tunable lasers is analyzed and a dc pilot tone assisted phase noise mitigation technique is proposed for a fast wavelength switching dual-polarization orthogonal frequency-division multiplexed transceiver. This enables the use of commercially available digital supermode distributed Bragg reflector lasers in both the transmitter and receiver in an 800-km wavelength routed coherent network that exhibits a variable path history.