抑制LOFDM系统PAPR非线性压扩变换算法  

Nonlinear companding transform for PAPR reduction in lattice-OFDM system

作　　者：彭斯明 沈越泓[1] 袁志钢[1] 苗誉威[2] 简伟[1] 

机构地区：[1]解放军理工大学通信工程学院,江苏南京210007 [2]济南军区通信网络技术管理中心,山东济南250002

出　　处：《通信学报》2015年第3期215-222,共8页Journal on Communications

基　　金：国家自然科学基金资助项目(60772083;61201242);江苏省自然科学基金资助项目(BK2012057);解放军理工大学预研基金资助项目(KYTYZLXY1208)~~

摘　　要：针对网格正交频分复用(LOFDM,lattice OFDM)系统具有较传统OFDM系统更高峰均功率比(PAPR,peak-to-average power ratio)的问题,在将传统非线性压扩变换应用于LOFDM系统的同时研究并分析了一种新的基于原信号统计分布特性的连续可导非线性压扩算法。该算法从原信号的渐进高斯分布特性出发并对原信号的幅度分布函数进行截断逼近,在保持平均功率不变的条件下,将压扩后的信号限制在与原信号分布特性一致的特定范围内,使压扩后的信号在保持其原有分布特性的同时,能更大程度改善系统PAPR和误比特(BER,biterror ratio)性能。理论分析和仿真实验表明,所提出的算法性能要显著优于传统非线性压扩算法。Since the inherent higher peak-to-average power ratio （PAPR） in lattice OFDM （LOFDM） is higher than that of conventional OFDM systems, a novel continuous and differentiable nonlinear companding scheme is investigated and analyzed when employing the conventional companding transforms. By making full use of the characteristic of the Gaus- sian-distributed original signals and employing a truncation to the distribution function of the original signals, the com- panded signals can be restricted in a specific region which consistents with the distribution of original signals. Therefore, the companded signals can not only achieve an improved PAPR and bit error ratio （BER） performance but also maintain the statistical characteristics of the original signals. Theoretical analysis and simulation results demonstrate that the pro- posed scheme substantially outoerform~ the t^c^nve.ntinn^l nc^nll ,4~ 1-

关 键 词：网格正交频分复用 峰均功率比 非线性压扩变换 概率分布函数 

分 类 号：TN919.72[电子电信—通信与信息系统]