Title
Weighted finite impulse response filter for chromatic dispersion equalization in coherent optical fiber communication systems
Abstract
Time-domain CD equalization using finite impulse response (FIR) filter is now a common approach for coherent optical fiber communication systems. The complex weights of FIR taps are calculated from a truncated impulse response of the CD transfer function, and the modulus of the complex weights is constant. In our work, we take the limited bandwidth of a single channel signal into account and propose weighted FIRs to improve the performance of CD equalization. The key in weighted FIR filters is the selection and optimization of weighted functions. In order to present the performance of different types of weighted FIR filters, a square-root raised cosine FIR (SRRC-FIR) and a Gaussian FIR (GS-FIR) are investigated. The optimization of square-root raised cosine FIR and Gaussian FIR are made in term of the bit rate error (BER) of QPSK and 16QAM coherent detection signal. The results demonstrate that the optimized parameters of the weighted filters are independent of the modulation format, symbol rate and the length of transmission fiber. With the optimized weighted FIRs, the BER of CD equalization signal is decreased significantly. Although this paper has investigated two types of weighted FIR filters, i.e. SRRC-FIR filter and GS-FIR filter, the principle of weighted FIR can also be extended to other symmetric functions super Gaussian function, hyperbolic secant function and etc.
Year
DOI
Venue
2017
10.1117/12.2300529
Proceedings of SPIE
Keywords
Field
DocType
optical communications,optical fiber,chromatic dispersion
Discrete mathematics,Raised-cosine filter,Digital filter,Half-band filter,Linear filter,Control theory,Infinite impulse response,Algorithm,Low-pass filter,Adaptive filter,Mathematics,Filter design
Journal
Volume
ISSN
Citations 
10617
0277-786X
0
PageRank 
References 
Authors
0.34
0
4
Name
Order
Citations
PageRank
Ziyi Zeng100.34
Aiying Yang200.34
Peng Guo300.68
Lihui Feng431.43