On generalized orthogonal spreading sequences for quasi synchronous CDMA system

Based on equidistant code, a method for obtaining spreading sequences with zero correlation zone (ZCZ) or low correlation zone (LCZ) is proposed, these spreading sequences can be employed in approximately synchronized code division multiple access (AS-CDMA) system to eliminating multiple access and multipath interference. In addition, lower bounds on correlation function of such sequence set are unproved, a new lower bound, for those ZCZ sequences which don't meet lower bound, is presented.