大规模MIMO中ZC码导频设计的研究

Research on ZC Code Pilot Design in Massive MIMO

针对大规模MIMO系统中存在的导频污染问题,论文提出了一种基于ZC(Zadoff-Chu)序列的导频序列设计方法。与现有的采用序列长度为奇数的ZC序列导频序列设计方法不同,论文利用序列长度为偶数的ZC序列作为基序列,利用偶数ZC序列在满足循环位移量之和为奇数的条件下互相关值极小的特点,结合偶数小区成对分区方法,设计导频序列。考虑其它小区导频污染的情况下,通过接收导频序列进行信道估计,在估计过程中对变量只采用乘加运算,不需要对变量进行除法及求逆运算,所提方法相比于传统LS估计方法精度更高,比MMSE方法计算量少,在简化了信道估计运算量的同时,提高了信道估计准确性。

A pilot design method based on ZC（Zadoff-Chu）sequence as a base sequence is proposed for the problem of pilot pollution in massive MIMO systems.It is different from the current ZC sequence with odd length,it presents a ZC sequence with even length as the basis of the pilot,utilizing the characteristic of cross correlation value is very small under the condition that if the sum of cyclic displacement is odd,and then combing even cells partition method in pairs.Considering the pilot pol-lution of other cells,the channel estimation is processed by receiving the pilot.In the process of channel estimation,the variables is only calculated by multiplication and add operation,no division and inverse operation,the proposed method is more accurate than the traditional LS estimation method,computation is less than the MMSE method,which simplifies the channel estimation calculation and improve the channel estimation accuracy.