基于分数阶Fourier变换减小OFDM系统PAPR的研究

介绍了基于分数阶Fourier变换的OFDM系统,给出了这种系统中经过变换后的信号的表达形式,探讨了该系统在不同的调制方式下（QAM调制和QPSK调制）使用Clipping算法降低系统PAPR的情况,并使用Matlab对不同阶数的CCDF进行了仿真。仿真结果表明,QAM调制下基于分数阶Fourier变换的Clipping算法性能不如基于傅立叶变换的Clipping算法好,而在QPSK调制方式下基于分数阶Fourier变换的OFDM系统PAPR性能比基于傅立叶变换的OFDM系统性能有了显著的提高。

Study on Reduction of Peak-to-average Power Ratio in OFDM System Based on Fractional Fourier Transform

In this paper, the OFDM system based on fractional Fourier transform （FRFT） is presented, the expression of signal in this system is given, the clipping algorithm for lowering the PAPR under different modulations （QAM modulation and QPSK modulation） for OFDM systems based on FRFT, is described. And with Matlab, the complementary cumulative distribution function （CCDF） with different fractional angle is simulated. Simulation indicates that the performance of clipping algorithm based on FRFF is not as good as that of clipping algorithm based on FFT under the QAM modulation, and however, under the QPSK modulation the PAPR performance of clipping algorithm based on FRFF is much better than that based on FFT.