Weiyang Mo

Neural Network Based Wavelength Assignment in Optical Switching

Greater network flexibility through software defined networking and the growth of high bandwidth services are motivating faster service provisioning and capacity management in the optical layer. These functionalities require increased capacity along with rapid reconfiguration of network resources. Recent advances in optical hardware can enable a dramatic reduction in wavelength provisioning times in optical circuit switched networks. To support such operations, it is imperative to reconfigure the network without causing a drop in service quality to existing users. Therefore, we present a system that uses neural networks to predict the dynamic response of an optically circuit-switched 90-channel multi-hop Reconfigurable Optical Add-Drop Multiplexer (ROADM) network. The neural network is able to recommend wavelength assignments that contain the power excursion to less than 0.5 dB with a precision of over 99%.

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.

Proactive and Nondisruptive Channel Probing for Wavelength Switching in Optical Transmission

Proactive and nondisruptive channel probing is investigated for the measurement of channel power, amplifier channel gain, and optical signal-to-noise ratio (OSNR) without disrupting established wavelength-division multiplexed channels. Using a nondisruptive probe signal over a three-span link, wavelength switching-induced power excursions are predicted to be within ±0.2 dB, and OSNR as high as 20 dB is accurately measured with a maximum of 0.5 dB error.

OFDM pilot-tone assisted distributed control for SDN-based elastic optical networks

We demonstrate for the first time an SDN-based OFDM elastic optical network with pilot-tone assisted distributed control. Improvement in spectral efficiency and a fast reconfiguration time of 30ms have been achieved in our experiment.