OFDM/OQAM系统中的干扰近似导频搜索算法

摘要

Interference Approximate Method(IAM)for OFDM/OQAM channel estimation needs to know the position of preamble, thus is inapplicable for un-cooperative communications. For this problem, the paper introduces an IAM preamble searching algorithm. The symbols before and after preamble are null symbols. After OFDM/OQAM imaginary intrinsic interference and channel fading, the phases of symbols before and after preamble are same. The characteristic can be used to determine the preamble position. Simulation results show that the preamble searching algorithm has a high correct percentage in low SNR regime when the value of preamble is high and the number of OFDM symbols is small.%非合作通信背景下，针对利用干扰近似法（Interference Approximate Method，IAM）进行OFDM/OQAM系统信道估计需要导频序列位置作为先验信息的问题，提出一种IAM导频搜索算法。IAM导频符号前后时隙为全0符号，经过OFDM/OQAM虚部干扰和信道衰落后导频前后时隙符号相位相同，利用此特征可以判定IAM导频符号位置。仿真实验表明导频符号值较大，多载波符号较少时，搜索算法在低信噪比条件下具有较高的搜索正确率。