（中國傳媒大學,北京,100024）
摘要：過高的峰值平均功率比(Peak-to-Average Power Ratio, PAPR) 是正交頻分復用技術(Orthogonal Frequency Division Multiplexing, OFDM)的一個主要缺陷。PAPR 抑制技術的應用可以最大限度地減小功率放大器的非線性失真, 提高功率放大器(High Power Amplifier, HPA)的效率。在各種抑制PAPR的算法中，基于削波的方法由于其簡單易實現的特性得到廣泛應用。在做PAPR抑制時，采用削波的方式往往需要多次迭代，同時不同的削波方式對其性能也有不同的影響。在本文中，分析和比較了兩種削波方式對PAPR、收斂速度及平均功率的影響。仿真結果表明，削波后保持所有子載波幅值相同時，PAPR抑制更明顯，收斂速度也更快，但平均功率增加會非常大。
關鍵詞：峰值平均功率比；正交頻分復用；削波；收斂速度
Analysis and Comparison of Two Clipping Methods in PAPR Reduction for OFDM System
Liang Yao, Jing He, Xinyu Xu
(Communication University of China, Beijing, 100024, yaoliang@cuc.edu.cn)
Abstract: High PAPR (Peak-to-Average Power) is one of the major drawbacks of OFDM systems. To improve the HPA efficiency and reduce nonlinear distortion, PAPR reduction techniques are used. Various PAPR reduction techniques have been proposed, and clipping based methods are attractive for its simplicity and easy implementation. Clipping based methods generally are iterative. Different clipping method leads to different performance. In this paper, two clipping methods, clipping and enlipping, are analyzed and compared in terms of PAPR, convergent rate and increase of average power. The simulation results show that enlipping can achieve faster convergent rate, but the average power is increased significantly which will incur degradation of overall system performance.
Keywords: PAPR; OFDM; clipping; convergent rate
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作者簡介：姚亮（1987-），男，碩士，主要研究方向現代電子設計。
