一种改进的基于循环前缀的OFDM系统定时同步方法

同步是正交频分复用(OFDM,Orthogonal Frequency-Division Multiplexing)系统研究的关键问题之一,本文主要研究了基于循环前缀(CP,Cyclic Prefix)的OFDM系统定时同步方法.传统的基于循环前缀的OFDM系统定时同步方法只局限于在一个符号内进行相关运算,同步效果不够理想,而且在多径信道存在的情况下循环前缀的长度大都比较长才能正确确定符号定时点,降低了传输效率.本文提出了一种扩展的多符号联合定时同步算法,仿真结果显示,改进后的方法提高了传输速率,在符号同步估计性能较原始方法有显著的提高.

A Modified Timing Synchronication Method Based on Cyclic Prefix in OFDM Systems

Synchronization is a key problem of orthogonal frequency division multiplexing (OFDM) system,timing synchronization methods based on cp (cyclic prefix) are researched in this paper.The correlation function and the power function of conventional timing synchronization method based on cp are carried out over only one OFDM symbol,which makes synchronization performance dissatisfied,at the same time,the length of cp under multipath environment which is usually longer can correctly ascertain symbol timing point so as to decline transmission rate.An extended method is proposed in this paper,simulation results show that the modified method improves transmission rate and has a prominent performance improvement than the conventional method.