摘要
正交频分复用(Orthogonal Frequency Division Multiplexing,简称OFDM)是一种多载波调制技术,是4G的核心技术。但OFDM系统的主要缺陷之一是对同步误差非常敏感,尤其是频率偏差,很小的频率偏差就会导致系统性能的急剧下降。本文针对OFDM系统的频率同步问题,首先介绍了OFDM系统模型,然后介绍了频率偏差对OFDM系统的影响,最后重点讨论了两种频率同步算法。在AWGN信道下对两种算法进行了仿真实验,比较了两种算法的估计精度、复杂度以及估计范围。
Orthogonal Frequency Division Multiplexing （OFDM）, the core technology of 4G, is a multi-carrier modulation technique. However, OFDM system is very sensitive to synchronous errors, especially the frequency offset. This is one of the major defect in OFDM system. A very small frequency offset will lead to degeneration of the system performance dramatically. This paper aims at the problems of frequency synchronization in the OFDM system. Firstly, a OFDM system model is introduced. Secondly, the effects of frequency offset for the OFDM system are described. Finally, two kinds of frequency synchronization algorithm are discussed. The accuracy, complexity and the estimated scope of two algorithms are compared using computer simulation in additive white Gaussian noise channel（AWGN）.
出处
《微计算机信息》
2010年第27期60-62,共3页
Control & Automation
