Open AccessOn the long-memory filtering gain in optical high-order QAM transmission systems
Author(s) -
Wen-Chih Peng,
Hidenori Takahashi,
Takehiro Tsuritani,
Ramon Casellas
Publication year - 2013
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.21.011021
Subject(s) - transmitter , computer science , qam , transmission (telecommunications) , quadrature amplitude modulation , filter (signal processing) , optics , electronic engineering , optical communication , uncorrelated , telecommunications , bit error rate , physics , decoding methods , channel (broadcasting) , mathematics , engineering , statistics , computer vision
In this paper, we verify the effectiveness of the last-stage long memory filter (LMF) in mitigating the long-memory response (LMR) of hardware, i.e. the transmitter and receiver. Based on the experimental results, we draw the following conclusions: 1) LMF can effectively mitigate the LMR impact, such as transmitter reflections, and its efficiency is more significant for high-order QAM signals. 2) Using LMF, a partially-correlated pattern exhibits similar performance to that of an uncorrelated pattern both in back-to-back and after 320-km standard single mode fiber (SSMF) transmission. Moreover, a simple solution to the computational complexity of LMF, effective-tap (ET) LMF, is proposed and demonstrated.