Open AccessInvestigation of wired and wireless services based on OFDM DSB-RC transmission in the presence of modulation chirp of a DEMZM
Author(s) -
Paulo Almeida,
Henrique Silva
Publication year - 2013
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.21.030764
Subject(s) - chirp , compatible sideband transmission , modulation (music) , physics , sideband , optics , optical carrier transmission rates , orthogonal frequency division multiplexing , electro optic modulator , intensity modulation , electronic engineering , telecommunications , phase modulation , optical modulator , phase noise , computer science , acoustics , radio over fiber , optical fiber , engineering , microwave , laser , channel (broadcasting) , quantum mechanics
In this paper, we investigate the performance of intensity modulation with optical carrier reduced by biasing a dual-electrode Mach-Zehnder modulator (DEMZM) below its quadrature point, in the presence of controlled modulation chirp. The effects of the modulation chirp and of the bias point of a DEMZM on the received signal are analytically derived for small-signal operation. The interaction of these two effects is assessed in terms of optical signal to noise ratio (OSNR) required for a BER = 10(-9), through a comparison between double sideband (DSB) modulation and double sideband - reduced carrier (DSB-RC) modulation, by numerical simulation. We found that the power of the optical carrier has impact on the optimum value of the α chirp parameter and that a positive value of the α chirp parameter can be the optimum value to drive a DEMZM, depending on the central frequency of the orthogonal frequency division multiplexing (OFDM) signal and on the DEMZM bias point.