A Geometrical Approach for Maximum Likelihood Estimation of Multipath

Nuria Blanco-Delgado, Fernando D. Nunes, Joao M. Xavier

Abstract:	This paper considers a geometrical approach for delay estimation of line-of-sight (LOS) and multipath signal components for BPSK and BOC modulated signals in multicorrelator GNSS receivers. The estimation can be performed up to the correlators spacing by applying a maximum likelihood estimator (MLE). Previous attempts to solve the multipath problem by using the MLE implied either a brute force approach to find the maximum by a search over a minimum of 6 parameters which would be computationally demanding [1] or the adoption of iterative solutions whose convergence could not be assured [2]. Furthermore, the present technique allows discerning multipath signals with relative delays to the LOS as small as the correlators’ distance. The intended estimation approach together with the fact that large amount of operations can be precomputed and stored in memory makes the proposed method computationally efficient and fast enough to be considered for real time computations. Furthermore, simulation results show that the proposed algorithm outperforms classical solutions like Narrow Correlator and Double-Delta techniques
Published in:	Proceedings of the 21st International Technical Meeting of the Satellite Division of The Institute of Navigation (ION GNSS 2008) September 16 - 19, 2008 Savannah International Convention Center Savannah, GA
Pages:	679 - 688
Cite this article:	Blanco-Delgado, Nuria, Nunes, Fernando D., Xavier, Joao M., "A Geometrical Approach for Maximum Likelihood Estimation of Multipath," Proceedings of the 21st International Technical Meeting of the Satellite Division of The Institute of Navigation (ION GNSS 2008), Savannah, GA, September 2008, pp. 679-688.
Full Paper:	ION Members/Non-Members: 1 Download Credit Sign In