title: A simple and efficient frequency offset estimation algorithm for high-speed coherent optical OFDM systems.
abstract: 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.
authors.affiliation: Institute of Advanced Network Technology and new Services (ANTS), University of Science & Technology Beijing (USTB), No.30 Xue Yuan Road, Haidian, Beijing 100083, China.
authors.forename: Xian
authors.initials: X
authors.lastname: Zhou
authors.forename: Keping
authors.initials: K
authors.lastname: Long
authors.forename: Rui
authors.initials: R
authors.lastname: Li
authors.forename: Xiaolong
authors.initials: X
authors.lastname: Yang
authors.forename: Zhongshan
authors.initials: Z
authors.lastname: Zhang
mesh_terms: D000465:Algorithms; D055096:Optical Devices; D012815:Signal Processing, Computer-Assisted; D013685:Telecommunications