联合迭代滤波与压扩参数优化的OFDM信号峰平比抑制  

Companding transform technique combined with iterative filtering for reducing PAPR of OFDM signals

作　　者：杨超[1] 王勇[1] 葛建华[1] 

机构地区：[1]西安电子科技大学综合业务网理论及关键技术ISN国家重点实验室,陕西西安710071

出　　处：《通信学报》2015年第4期163-169,共7页Journal on Communications

基　　金：国家自然科学基金资助项目(61101145);国家科技重大专项基金资助项目(2012ZX03001008);111基地基金资助项目(B08038)~~

摘　　要：针对现有基于压扩变换处理的信号峰平比抑制方法性能单一且参数固定等缺陷,提出一种联合迭代滤波与自适应压扩参数优化的OFDM信号峰平比抑制方案。该方案能够同时对信号的峰平比PAPR和接收端误码率BER性能进行联合优化,并在迭代过程中有效消除因信号幅度畸变所引起的带外频谱再生;所提信号压扩及解压扩函数形式简单,计算复杂度较小;推导并给出了该方案可获得的PAPR抑制增益和BER理论性能界。仿真结果表明,该方案可同时获得较好的信号PAPR抑制、误码率以及带外功率谱性能,并在迭代过程中对压扩参数进行自适应调整,能够有效提高算法的适用灵活性。Considering the drawbacks of the traditional companding transforms, an efficient companding scheme com- bined with iterative filtering was proposed to reduce the peak-to-average power ratio （PAPR） of orthogonal frequency di- vision multiplexing （OFDM） signals. By introducing a joint optimization approach for PAPR and bit error rate （BER） performances along with remaining an unchanged average output power level, the scheme could achieve significant re- duction in PAPR as well as an improved BER simultaneously. Moreover, by adaptively adjusting the transform parame- ters in the iterative process, more design flexibility in companding form and lower out-of-band radiation could also be given to satisfy various system requirements. The proposed scheme had a simple functional form and less computational complexity. The theoretical results regarding the transform gain and impact of companding distortion were derived. Simulation results show that this scheme can substantially offer better overall performances in terms of PAPR reduction, BER performance and bandwidth efficiency.

关 键 词：正交频分复用 峰平比 压扩变换 参数优化 

分 类 号：TP393[自动化与计算机技术—计算机应用技术]