【作者】 张军；

【导师】 吕振肃；

【作者基本信息】 兰州大学 ， 通信与信息系统， 2007， 硕士

【摘要】 正交频分复用(OFDM)技术属于多载波调制技术(MCM)的一种，它以其良好的特性成为下一代移动通信领域研究的重点。但是其特有的调制方式决定了它存在着较高的峰值平均功率比(PAPR)。较大的PAPR值对于OFDM系统发送端的功率放大器的线性度提出了很高的要求，同时也增加了A／D和D／A转换器的复杂度并且降低了它们的准确性。因此，如何有效地降低OFDM系统的PAPR值将直接关系着整个OFDM系统的性能，进而影响到该技术在未来移动通信领域的广泛应用。本文以OFDM技术在移动通信领域的应用为背景展开讨论，详细论述了OFDM系统的PAPR的相关问题。探讨了目前较为常用的降低OFDM系统PAPR的三类方法，主要包括信号畸变技术、编码类技术和非畸变技术。同时就各类方法在降低OFDM系统PAPR的性能特点方面做了深入细致的分析。并结合自己的学习情况，就非畸变技术中的选择性映射(SLM)方法以及部分传输序列(PTS)方法做了相应的改进，在保证降低系统PAPR效果的基础上减小了系统计算的复杂程度。其中，对SLM方法的改进主要体现在对逆快速傅立叶变换(IFFT)模块数量的减小上，而对PTS方法则采用了寻求次优辅助信息的迭代算法，最后通过计算机仿真分析证明其可行性。更多还原

【Abstract】 The technology of Orthogonal Frequency Division Multiplexing (OFDM) is one of technology of Multi-carrier Modulation (MCM). It will become a hotspot in the fields of next generation communication for its good performance. However, the development of this technique is embarrassed by the drawback of high Peak-to-Average Power Ratio (PAPR).The power amplifier which lies in the transmission port must need wider dynamic range for adapting to high PAPR in OFDM system. At the same time, the convertor of A/D and D/A are became more complex and its veracity is debased for high PAPR. Therefore, it is very important for the performance and application of OFDM system to reduce effectively high PAPR.In this paper, we discussed many different traditional methods of reducing PAPR in system of mobile communication. Then, we analysed and compared the characteristic of different ways through simulation, including signal aberrance technique, coding technique and non-aberrance technique. After this we further improved the methods of Selected Mapping (SLM) and Partial Transmit Sequence (PTS) based on the analysis about traditional methods. We expect to decrease the complexity of SLM and PTS in the precondition of keeping effect of reducing PAPR. In detail, we decreased the number of IFFT module in method of SLM and chose the iterative algorithm of seeking hypo-optimization side information in method of PTS. Finally, we proved this assume by simulation.更多还原