An Improved Frame Synchronization for Optical OFDM Systems

Abstract:

Orthogonal frequency division multiplexing (OFDM) is applied to optical communication widely because of its robustness against channel dispersion and high spectral efficiency. But the synchronization between transmitter and receiver is a critical factor for system performances. This paper proposes an improved frame timing synchronization algorithm for optical OFDM system to keep synchronization by delay time compensation. The simulation of 40 Gb/s single-side-band (SSB) direct-detection optical OFDM system is setup and investigated. The curve of timing metric and the constellation of four-quadrature amplitude modulation (QAM) are given in the paper. And the transmission distance using the proposed method is compared with Park method. The simulation results show that the improved frame synchronization method promote the performances of optical OFDM system greatly. The distance can be 1600 km without dispersion compensation under the bit error ratio of 10-⁴.

• Periodical: Advanced Materials Research (Volume 571)
• Pages: 646-650
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.571.646
• Online since: September 2012
• Authors: Meng Liang, Rong Lu, Yuan Bo Wang, Jia Min Gong
• Keywords: Optical Orthogonal Frequency Division Multiplexing (O-OFDM), Synchronization, Training Symbol

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