Tracking Performance of the Blind Adaptive LMS Algorithm for Fading CDMA Systems
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.
Keywordsmultiple access interference (MAI) delay locked loop code acquisition tracking least mean square algorithm
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