OFDM在长距离光传输系统色散补偿中的应用

The application of OFDM for dispersion compensation in long-haul optical systems

为了降低光纤长距离传输中电域色散补偿(EDC,Electronic Dispersion Compensation)的实现复杂度,采用正交频分复用技术(OFDM,Orthogonal Frequency Division Multiplexing)与光单边带调制(OSSB,Optical Single Sideband),可有效实现光纤的色散补偿。文章介绍了基于光直接检测(DD,Direct-Detection)的OFDM系统,重点对系统色散补偿的实现进行了具体的数学分析,并进行了数字仿真,就系统误码率(BER)与传统光传输系统(NRZ,Non-Return-to-Zero)进行了比较。结果表明,较传统光传输中电域色散补偿,基于光直接检测的OFDM系统色散补偿实现简单,系统复杂度降低,同时也提高了系统性能。

In order to lower the complexity of EDC （Electronic Dispersion Compensation） for chromatic dispersion in long-haul optical transmission, the combination of Orthogonal Frequency Division Multiplexing （OFDM） and Optical Single Sideband Modulation （OSSB） can be used to adaptively compensate for chromatic dispersion in long-haul Standard Single-Mode Fiber （S-SMF） links. The paper introduces the optical OFDM systems based on direct-detection and analyses the theory of chromatic compensation. Additionally, simulation demonstrates that the performance of optical OFDM system based on direct-detection is substantially improved more than conventional NRZ system. With such a scheme, optical OFDM could be a simple and effective solution to completely compensate fiber chromatic dispersion in long-haul optical transmission.