摘要
正交频分复用(OFDM)技术是一种多载波调制方式。作为第四代移动通信系统的核心技术,OFDM己成为当今高速无线通信领域的研究热点。正交频分复用(OFDM)系统存在高峰值平均功率比(PAPR)问题,这一问题会导致系统性能降低,为其实用化设置了障碍。文中研究了一种改进的降低PAPR的非线性压缩与扩展算法,可以得到更好的PAPR性能。该方法的特点在于采用一种计算复杂度较低的非线性压扩函数,同时融合了叠加训练序列方法的改进非线性压扩算法,从而有效地降低系统PAPR。理论研究和仿真结果表明,与传统方法相比,所提出的改进压缩与扩展方法可以在降低系统复杂度的同时得到更好的PAPR性能。
Orthogonal Frequency Division Multiplexing(OFDM) technology is a Multicarrier modulation technology.As a core technology for 4G mobile communication system,OFDM has become a research focus in high-data-rate wireless communication field.The large peak to average power ratio(PAPR) problem existing in OFDM signal would reduce system performance and become one of the main obstacles for wide applications of OFDM.This paper proposes an improved companding transform method,which could achieve better PAPR performance,and optimize companding transform by using a function with low calculation complexity and integrating a superimposed training sequence so as to reduce the PAPR of the system.The theory study and computer simulation results show that this as companded method could effectively reduce system complexity and obtain better PAPR performance as compared with conventional as compared transform methods
出处
《通信技术》
2010年第5期4-6,共3页
Communications Technology
关键词
正交频分复用
峰均功率比
非线性压扩
OFDM
PAPR
superimposed training
nonlinear companding transform