摘要
针对降低峰均功率比(Peak-to-Average Power Ratio,PAPR)的主要技术的降低效果普遍不理想的情况,文中提出一种基于混沌序列低相关性的部分传输序列法(Chaotic Sequence with Low Correlation of Partial Transmission Sequence,CL-PTS)。该方法使用自相关性较低的数条混沌序列与原始信号相乘,经过快速傅里叶逆变换(Inverse Fast Fourier Transform,IFFT)降低OFDM系统的瞬时功率平均值。仿真结果表明,在互补累积分布函数(Complementary Cumulative Distribution Function,CCDF)为10^(-3)时,该方法降低PAPR的效果相比其他同类算法有1 dB左右的增益,但算法的计算复杂度过高且需消耗较多的频谱资源。在此情况下,提出了改进的相关性算法(Chaotic Sequence with Low Correlation of Modified Partial Transmission Sequence,CM-PTS),分析了PTS算法的子块数对计算量的影响。利用IFFT变换的特点,通过改变序列在系统中的插入位置达到降低PAPR的目的。实验结果表明,CM-PTS算法在增加较少计算量的同时可以使PAPR的值降低约0.5 dB,同时不会引起误比特率的提高。
After analyzing the main techniques to reduce the peak to average power ratio(PAPR),a partial transmission sequence method(CL-PTS)based on low correlation of chaotic sequences is proposed to solve the problem that the reduction effect is gene-rally not ideal.In this method,several chaotic sequences with low autocorrelation are multiplied by the original signal,and the average instantaneous power of OFDM system is reduced by inverse fast Fourier transform(IFFT).Simulation results show that when the complementary cumulative distribution function(CCDF)is 10^(-3),the PAPR reduction effect of this method is about 1 dB compared with other similar algorithms,but the algorithm is too complex and consumes more spectrum resources.On this basis,an improved correlation algorithm(CM-PTS)is proposed.This paper analyzes the influence of the number of sub blocks of PTS algorithm on the amount of computation and using the characteristics of IFFT transform,the PAPR can be reduced by changing the insertion position of the sequence in the system.The results show that CM-PTS algorithm can reduce the PAPR value by about 0.5 dB without increasing the BER.
作者
赵耿
王超
马英杰
ZHAO Geng;WANG Chao;MA Ying-jie(School of Telecommunication Engineering,Xidian University,Xi’an 710071,China;Beijing Electronic Science and Technology Institute,Beijing 100070,China)
出处
《计算机科学》
CSCD
北大核心
2022年第5期250-255,共6页
Computer Science
基金
国家自然科学基金(61772047)
北京电子科技学院一流学科建设项目(3201017)。
关键词
正交频分复用
部分传输序列
混沌序列
峰均功率比
低相关性
Orthogonal frequency division multiplexing
Partial transmission sequence
Chaotic sequences
Peak to average power ratio
Low correlation
