A simple, low cost and robust scheme for optical orthogonal frequency division multiplexing (OOFDM) symbol synchronization is proposed and experimentally tested. The main idea is to load a direct current (DC) signal on a special subcarrier to achieve OFDM symbol synchronization at the receiver.
This techniqueis applicable to OFDM-PON (OFDM-passive optical network) system without additional bandwidth as the first zero subcarrier does not have any signal loaded originally. Using the proposed scheme, a real-time optical OFDM signal transmission at 2.667 Gbit/s over 20 km standard single-mode fiber is achieved. This scheme also offers an additional network security mechanism on the physical layer. Most importantly, it provides online real-time symbol synchronization for point-to-point and point-to-multipoint OOFDM network.
NI Bao-jing, LI Ying-chun, HAN Jing-long, JIANG Peng, FU Lei
. A New Technique of Symbol Synchronization for OOFDM[J]. Journal of Shanghai University, 2013
, 19(2)
: 132
-137
.
DOI: 10.3969/j.issn.1007-2861.2013.02.005
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