Zero correlation window(ZCW)or zero correlation zone(ZCZ)sequence can be used in quasi-synchronous code division multiple access(QS-CDMA)system to eliminate multiple access and multipath interferences.However,as the length of ZCW or ZCZ increases,fewer sequences are available.Recently,a new concept,sequence set with group-wise zero correlation window is introduced,which can increase the number of available sequences for a QS-CDMA system.In this article,a new method for generating sequence set with group-wise zero correlation window is presented.This method is based on a Hadamard matrix of size N×N and a pair of Hadamard matrices of size M×M.Compared with previous methods,the proposed sequence set has a group-wise zero correlation window for both periodic and aperiodic cross-correlation functions.
WANG Yang-zhi XU Cheng-qian College of Information Science and Engineering,Yanshan University,Qinhuangdao 066004,China