Open AccessAll-optical Nyquist-OTDM to Nyquist-WDM conversion for high-granular flexible optical networks
Author(s) -
Satoshi Shimizu,
Gabriella Cincotti,
Naoya Wada
Publication year - 2017
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.25.003496
Subject(s) - nyquist–shannon sampling theorem , optics , wavelength division multiplexing , physics , nyquist frequency , optical filter , signal (programming language) , multiplexing , multiplexer , electronic engineering , computer science , telecommunications , wavelength , bandwidth (computing) , engineering , programming language
We have proposed and experimentally demonstrated all-optical multiplexing (MUX)-format conversion from Nyquist optical time division multiplex (OTDM) to Nyquist wavelength division multiplex (WDM). The system is simply configured with a straight-type phase modulator (PM) driven by a sinusoidal wave and an optical Nyquist filter. In the theoretical investigation, it is proved that the single Nyquist signal is completely converted to Nyquist WDM signal, which consists of two half-baud-rate signals with different carrier frequencies. The theoretical modulation voltage for the phase modulator is slightly lower than Vπ: 0.913 Vπ, and it is experimentally verified. In the experimental demonstrations, 50 Gbaud to 25 Gbaud x 2 and 25 Gbaud to 12.5 Gbaud x 2 conversions are successfully demonstrated with quite low optical signal-to-noise ratio (OSNR) penalties. In addition, cascaded MUX-format conversion is also demonstrated; 50 Gbaud Nyquist signal is converted to four channels of 12.5 Gbaud Nyquist signals.