On the performance of Walsh-LS codes in CDMA systems

Walsh-LS-CDMA (WLS-CDMA) systems is a novel concept employing loosely synchronous (LS) codes and Walsh codes. The Walsh-LS spreading codes exhibit an interference free window (IFW) in the auto-correlation and cross-correlation functions, which has the potential to suppress inter symbol interference (ISI) and multiple access interference (MAI), resulting in increased capacity compared to traditional CDMA systems. In this paper the perspective of WLS-CDMA is explored. It is found that the forward-link has better performance than traditional CDMA systems, however in the reverse-link the Walsh-LS codes lose orthogonality