Conference Paper

A genetic algorithm based finger selection scheme for UWB MMSE rake receivers

Department of Electrical Engineering, Princeton University, Princeton, New Jersey, United States
DOI: 10.1109/ICU.2005.1569977 Conference: Ultra-Wideband, 2005. ICU 2005. 2005 IEEE International Conference on
Source: IEEE Xplore

ABSTRACT Due to a large number of multipath components in a typical ultra wideband (UWB) system, selective rake (SRake) receivers, which combine energy from a subset of multipath components, are commonly employed. In order to optimize system performance, an optimal selection of multipath components to be employed at fingers of an SRake receiver needs to be considered. In this paper, this finger selection problem is investigated for a minimum mean square error (MMSE) UWB SRake receiver. Since the optimal solution is NP hard, a genetic algorithm (GA) based iterative scheme is proposed, which can achieve near-optimal performance after a reasonable number of iterations. Simulation results are presented to compare the performance of the proposed finger selection algorithm with those of the conventional and optimal schemes.

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