A constant false alarm rate detector for antenna diversity CDMA systems

This paper describes a novel path selection algorithm for choosing multi-path components for RAKE recombination in antenna diversity CDMA systems. This paper extends previous work on a single-antenna path selection algorithm by considering diversity reception, namely the 2D-RAKE receiver. The 2D-RAKE is described, and the algorithm is developed for use with this receiver. The resulting new algorithm will be shown to fall into the class of optimal detectors known as Constant False Alarm Rate (CFAR). As the name implies, such a detector has a fixed probability of false alarm, independent of the input signal and noise statistics. Not only is this algorithm CFAR, but it maintains a high detection probability. Simulations of 2D-RAKE receivers are undertaken in the context of a 3GPP-compliant system and the mathematical analysis for this detector is confirmed by these simulations.