Tracking Performance of the Blind Adaptive LMS Algorithm for Fading CDMA Systems

Abstract

Abstract. Reliable and accurate time delay estimation is an important signal processing problem and is critical to a diverse set of applications. Multi-user receivers in asynchronous Code Division Multiple Access (CDMA) systems require the knowledge of several parameters including delay estimates between users. In this paper, we address this problem by proposing a novel approach based on blind least mean squares (LMS) based early-late delay tracker. Analytical expressions have been derived and simulation results of the proposed delay tracker are compared with the classical delay locked loop (DLL) approach in a multipath fading scenario. These results show that the proposed delay tracker provides very good tracking performance in challenging cases of multipath delays.