Robust channel estimation for ultra-wide band communications
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Abstract
UWB (ultra-wide band) systems transmit low power signals through communication channels that operate in closed environments and in short distances resulting in multiple propagation trajectories. Moreover, the noise affecting these channels can be characterized by the use of statistical models with heavier tails that the ones exhibited by gaussian distribution. This article proposes a robust approach for the estimation of the parameters of UWB channels based on the weighted median. More specifically, it develops an algorithm of greedy search that exploits the low density characteristic of the channel’s impulsive response, in which the gains and delays of the relevant channels are determined by applying the weighted median on an scaled and displaced version of the signal received. This newly introduced algorithm is evaluated using extensive simulations in which the performance of the proposed algorithm surpasses the performance of the traditional greedy search algorithm for different levels of impulsive noise.
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References
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