Edge decision assisted decorrelators for asynchronous CDMA channels

Asynchronous decorrelating detector is a linens multiuser detector in code- division multiple-access (CDMA) environment. It has relatively good perform ance and low-computational complexity. However, the ideal asynchronous deco rrelating detector [3] requires the observation of the entire input hit seq uence. Implementation of this ideal detector based on long bit sequence res ults in long delays and high computational complexity. Lo fact, if the obse rved window does not corer the entire data sequence, the classical asynchro nous decorrelating detector is no longer near-far resistant. In this paper, we propose a method using initial decisions on bits for both edges of the finite observed window. These initial decisions are used to assist subseque nt decisions sf the whole sequence inside the observed window based on the decorrelating method, This new edge decision assisted decorrelator (EDAD) m ethod is shown to be near-far resistant.