Low Complexity FFT-Based Frequency Offset Estimation for M-QAM Coherent Optical Systems

Author

Junxiong Xiao ; Jie Feng ; Jilong Han ; Wei Li ; Rong Hu ; Qi Yang ; Shaohua Yu

Author_Institution

Wuhan Nat. Lab. for Optoelectron., Huazhong Univ. of Sci. & Technol., Wuhan, China

Volume

27

Issue

13

fYear

2015

fDate

July1, 1 2015

Firstpage

1371

Lastpage

1374

Abstract

Frequency offset estimation algorithms for M-ary quadrature amplitude modulation based on the maximization of the periodogram of fourth-power samples have been investigated. In this letter, a low complexity estimation algorithm using interpolated discrete Fourier transform approach is introduced to replace the gradient descent (GD) or the chirp z transform (CZT) methods. The numerical simulations and complexity analysis demonstrate that the proposed estimator has much lower computational complexity than that of GD and CZT without performance degradation.

Keywords

Fourier transform optics; computational complexity; discrete Fourier transforms; interpolation; optical communication; optimisation; quadrature amplitude modulation; M-QAM coherent optical systems; M-ary quadrature amplitude modulation; chirp z transform; complexity analysis; fast Fourier transform; fourth-power samples; frequency offset estimation; gradient descent method; interpolated discrete Fourier transform approach; low complexity FFT; low complexity estimation algorithm; periodogram maximization; Accuracy; Complexity theory; Discrete Fourier transforms; Frequency estimation; Frequency modulation; Optical polarization; Optical receivers; Coherent optical communication; Discrete Fourier transform (DFT); M-ary quadrature amplitude modulation (M-QAM); discrete Fourier transform (DFT); frequency offset estimation; interpolation;

fLanguage

English

Journal_Title

Photonics Technology Letters, IEEE

Publisher

ieee

ISSN

1041-1135

Type

jour

DOI

10.1109/LPT.2015.2421507

Filename

7083716