Open AccessA simple and efficient frequency offset estimation algorithm for high-speed coherent optical OFDM systems
Author(s) -
Xian Zhou,
Keping Long,
Rui Li,
Xiaolong Yang,
Zhongshan Zhang
Publication year - 2012
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.20.007350
Subject(s) - orthogonal frequency division multiplexing , algorithm , frequency offset , computer science , quadrature amplitude modulation , offset (computer science) , residual , multiplexing , frequency domain , polarization division multiplexing , electronic engineering , signal processing , bit error rate , telecommunications , engineering , channel (broadcasting) , decoding methods , radar , computer vision , programming language
In this paper, we propose a simple frequency offset estimation (FOE) algorithm for high-speed coherent optical orthogonal frequency-division multiplexing (CO-OFDM) systems, which avoids the exhaustive search computations on the integer part of FOE by using a merit function. In time domain, the FOE algorithm can estimate all the frequency offset in the range of [-5GHz, +5GHz], for satisfying the practical application requirement, based on only one redesigned training symbol. In addition, we provide the theoretical analysis about the quantitative influences of the residual frequency offset (RFO) on CO-OFDM systems. In order to reduce the final estimation error, a new zero-overhead residual frequency offset estimation (RFOE) algorithm is also proposed in this paper. Finally, the feasibility and effectiveness of the proposed FOE and RFOE algorithms are demonstrated in a 464 Gbit/s polarization-division multiplexed (PDM) 16-ary quadrature amplitude modulation (QAM) CO-OFDM system by the simulation, and numerical results validate the proposed algorithms.