Open AccessLow-complexity joint symbol synchronization and sampling frequency offset estimation scheme for optical IMDD OFDM systems
Author(s) -
Zhen Zhang,
Qianwu Zhang,
Jian Chen,
Yingchun Li,
Yingxiong Song
Publication year - 2016
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.24.012577
Subject(s) - orthogonal frequency division multiplexing , computer science , synchronization (alternating current) , asynchronous communication , transmission (telecommunications) , transmission system , algorithm , electronic engineering , telecommunications , channel (broadcasting) , engineering
A low-complexity joint symbol synchronization and SFO estimation scheme for asynchronous optical IMDD OFDM systems based on only one training symbol is proposed. Numerical simulations and experimental demonstrations are also under taken to evaluate the performance of the mentioned scheme. The experimental results show that robust and precise symbol synchronization and the SFO estimation can be achieved simultaneously at received optical power as low as -20dBm in asynchronous OOFDM systems. SFO estimation accuracy in MSE can be lower than 1 × 10 -11 under SFO range from -60ppm to 60ppm after 25km SSMF transmission. Optimal System performance can be maintained until cumulate number of employed frames for calculation is less than 50 under above-mentioned conditions. Meanwhile, the proposed joint scheme has a low level of operation complexity comparing with existing methods, when the symbol synchronization and SFO estimation are considered together. Above-mentioned results can give an important reference in practical system designs.