Quasi-synchronous CDMA system using spreading sequences with zero-correlation zone

摘要

Current code-division multiple access (CDMA) systems are interference limited and suffer from both inter-symbol and multiple-access interference in time dispersive channel. The choice of the spreading sequences predetermines some properties of the system. Therefore, considerable efforts have been invested in designing zero-correlation zone sequences that exhibit the so-called interference-free window, where the autocorrelation and cross-correlation of the codes remain equal to zero. This research has drawn on the features of this sequences to improve the CDMA system performance.