OFDM系统中循环前缀作用的分析

Analysis of the Roles of Cyclic Prefix in OFDM System

近年来,正交频分复用(OFDM)技术已被越来越多的人所关注,并且在IEEE 802.11无线局域网中得到实际应用.在OFDM系统中一般要采用加入循环前缀(CP)的技术.本文从功率谱密度的角度分析了循环前缀的作用,并给出了仿真结果.结果表明,循环前缀的加入可以有效地消除符号间干扰(ISI)和子载波间干扰(ICI).

Recently orthogonal frequency division multiplexing （OFDM） has received more and more attention and has been applied to IEEE 802.11 wireless LAN. We usually apply cyclic prefix in OFDM system. In this paper, we analyses the roles of cyclic prefix by considering the power spectral density and present its simulation result. The results show that by adding the prefix cycle can effectively eliminate inter-symbol interference （ISI） and inter-carrier interference （ICI）.