Title :
Improved FFT-Based Frequency Offset Estimation Algorithm for Coherent Optical Systems
Author :
Yumin Liu ; Yunfeng Peng ; Shuang Wang ; Zonglong Chen
Author_Institution :
Beijing Eng. & Technol. Res. Center for Convergence Networks & Ubiquitous Services, Univ. of Sci. & Technol. Beijing, Beijing, China
Abstract :
Algorithms of frequency offset (FO) estimation based on fast Fourier transform of the sample signal´s argument have been investigated, in which the FO estimation range is [-Rs/12, Rs/8] (Rs is the symbol rate). In this letter, an improved algorithm is proposed with the sign of FO being determined by means of an improved judging method. The estimation range of the proposed algorithm can be up to [-Rs/8,Rs/8], with the same accuracy as that of the previous algorithms being obtained, yet at the same time requiring very little additional computational burden.
Keywords :
estimation theory; fast Fourier transforms; optical modulation; optical transmitters; quadrature amplitude modulation; quadrature phase shift keying; FO estimation; FO sign; coherent optical systems; estimation range; fast Fourier transform; improved FFT-based frequency offset estimation algorithm; improved judging method; sample signal argument; symbol rate; Estimation; Frequency estimation; Frequency modulation; OFDM; Optical modulation; Phase shift keying; Signal to noise ratio; Coherent optical communication; fast Fourier transform (FFT); frequency offset estimation; quadrature amplitude modulation (QAM); quadrature phase shift keying (QPSK);
Journal_Title :
Photonics Technology Letters, IEEE
DOI :
10.1109/LPT.2014.2301796
