Abstract
Semiconductor optical amplifier (SOA) is a promising candidate for metro and access networks thanks to its wide amplification bandwidth and potential low cost. However, in wavelength-division-multiplexing (WDM) systems, nonlinear cross gain modulation (XGM) can degrade the transmission performances by inducing strong cross-talk between WDM channels. Recently, differential phase-shift keying (DPSK) modulation has attracted much interest for its enhanced immunity against the effects of XGM nonlinearities [1]. DPSK signals can be obtained by biasing a single Mach-Zehnder Modulator (MZM) at a null, and using a high-power RF driver amplifier with Vp-p ~ 2Vπ to have a phase shift between 0 and π. Employing an intensity modulator, instead of a pure phase one to generate optical DPSK can have the advantage that exact n phase shifts are produced. However, intensity modulation is present in the signal and can degrade the signal amplification through SOA by phase-amplitude coupling, especially if one operates near the SOA saturation power, as this can occur with a complete WDM comb.
© 2007 IEEE
PDF ArticleMore Like This
Tong Cao, Liao Chen, Yu Yu, and Xinliang Zhang
AF2B.3 Asia Communications and Photonics Conference (ACP) 2014
E. Ciaramella, A. D’Errico, V. Donzella, G. Contestabile, S. Betti, V. Carrozzo, F. Curti, and M. Guglielmucci
JThA75 National Fiber Optic Engineers Conference (NFOEC) 2007
Oladeji Akanbi, Jianjun Yu, Yong-Kee Yeo, Benny Bing, and Gee Kung Chang
CTuO5 Conference on Lasers and Electro-Optics (CLEO:S&I) 2005