OFDM系统峰均值比方法比较

The Comparison of Approaches for Reducing Peak-to-Average Power Ratio of OFDM System

IEEE802．16D作为定位于固定的宽带无线接入城域网标准，在系统容量和传输距离方面比无线局域网系统更有竞争优势，IEEE802．16D物理层采用OFDM作为主要的调制方法。OFDM系统存在着潜在的高峰均功率比（PAPR），在遇到射频功率放大器等非线性器件时，会发生严重的非线性畸变。本文重点分析并讨论了目前几种主要的OFDM峰均比改善方法，给出了几种峰均比减小的方案，并对各方案进行分析得出了各自的优缺点。

As the standard for fixed Broadband Wireless Access Metropolitan Area Network （MAN）, IEEE802. 16D has advantages over wireless LAN on system capacity and transmission distance. It employs OFDM as main modulation mechanism at physical layer. However, with potential high Peak-to-Average Power Ratio （PARP） in OFDM system, nonlinear distortion will occur when nonlinear devices such as RF power amplifier exist. This paper mainly discusses the main existing methods of improving PARP of OFDM system, gives some approaches of reducing PARP and analyzes the advantages and disadvantages of them.