考虑高斯误差和Doppler扩展的最大比合并性能分析  

The Impacts of Gaussian Error and Doppler spread on Maximal-Ratio Combining of Antenna Arrays

作　　者：李汉强[1] 郭伟[1] 郑辉[2] 

机构地区：[1]电子科技大学抗干扰通信国家重点实验室,四川成都610054 [2]信号盲处理国防科技重点实验室,四川成都610041

出　　处：《电子学报》2006年第1期24-30,共7页Acta Electronica Sinica

基　　金：国家自然科学基金(No.60472052)

摘　　要：在高斯误差和Doppler扩展条件下,研究信道估计时公共导频信道相关长度对天线阵的合并性能影响.假设信道估计通过相关WCDMA公共导频信道的N个符号来获得,文章首先推导了相干BPSK解调时平均BER性能的闭解表达式,然后利用该平均BER表达式对导频信道最优相关长度进行了分析,给出了最优相关长度的计算方法,并证明了最优相关长度N只与最大Doppler扩展f和符号周期有关,与阵列参数以及天线接收的信噪比无关.Maximum-ratio combining （MRC） is a simple and effective combining scheme for adaptive antenna arrays to combat fading. However, it requires estimation of the spatial signature （ i. e., the channel gain and phase at each antenna element） of the desired signal across the array. Assuming the channel estimation is obtained by N symbols＇ correlation using common pilot channel （CPICH）, we proceed to develop a fully analytical assessment of the impacts of Gaussian error and Doppler spread on the MRC performance. The originality of the approach revolves around the derivation of the closed-form expression for average bit error probability for coherent BPSK. The expression is then applied to find the optimal correlation length of channel estimation. As a result,the computing method of optimal correlation length has been given. It is also proved that the optimal correlation length N was only correlative with maximal Doppler spread fd and symbol duration.

关 键 词：天线阵列 最大比合并 非理想信道估计 高斯误差 Doppler扩展 

分 类 号：TN913.24[电子电信—通信与信息系统]