We propose and investigate a novel technique to realize non-return-to-zero (NRZ) to return-to-zero (RZ) format conversion of a multichannel 4-ary amplitude shift keying (4-ASK) signal. The proposed format converter composed of two modulators and a dispersion compensating fiber (DCF) is theoretically investigated using numerical simulation as basis. Research shows that a 4-channel 20-Gb/s NRZ-4-ASK signal can be converted to a RZ-4-ASK signal simultaneously without wavelength shifting and signal quality degradation, with the converted signal multiplexed to 40 Gb/s.
© 2010 Chinese Optics Letters
(060.2330) Fiber optics and optical communications : Fiber optics communications
(070.4340) Fourier optics and signal processing : Nonlinear optical signal processing
(230.0250) Optical devices : Optoelectronics
Wenke Yu, Caiyun Lou, Xiaofan Zhao, and Dan Lu, "Simultaneous multichannel NRZ-to-RZ format conversion of 4-ASK signal based on phase-intensity hybrid modulation and dispersion compensation fiber," Chin. Opt. Lett. 8, 859-862 (2010)