ACE改进算法降低CO—OFDM系统的PAPR

Improved ACE Algorithm for PAPR Reduction in CO-OFDM Systems

相干光正交频分复用（CO—OFDM）系统结合了相干光检测技术和OFDM技术的双重优点，对于实现长距离高速率大容量的光通信有明显的优势，近年来得到了广泛的研究。然而在CO—OFDM系统中同样存在高峰均功率比的问题，严重影响了系统的BER性能，为抑制光OFDM系统的PAPR，本文提出了两种复杂度较低的改进的动态星座图扩展方法，仿真结果表明，该方法与传统ACE算法相比能够明显的降低OFDM系统的PAPR，且能获得稳定的BER性能。

Coherent optical orthogonal frequency division multiplexing （CO-OFDM） system which has been extensively studied in recent years has combined the advantages of the coherent light detection technology and the OFDM technology, and therefore has obvious advantages in long-distance, high-speed, large-capacity optical com- munication. However,in CO-OFDM system,the high peak to average power ratio still exists,seriously affecting the BER performance of OFDM systems. To reduce the PAPR, this paper proposes two improved dynamic constellation expansion methods that have smaller computational complexity. The simulation results show that the methods can significantly reduce the PAPR of OFDM system, compared with the traditional method of ACE algorithm,while obtaining stable BER performance.