Root minimum variance toa estimation for wireless location

This paper addresses the TOA (Time Of Arrival) estimation problem for ranging applications in wireless location systems. High resolution first arrival path detector based on MV (Minimum Variance) and NMV (Normalized Minimum Variance) can provide an accurate TOA estimation even in high multipath scenarios and when LOS (Line-Of-Sight) signal is strongly attenuated. A new TOA estimator based on a polynomial rooting approach of the MV criterion, named RMV (Root Minimum Variance), is proposed in this paper. Performance of RMV TOA estimator is compared with the grid search MV and NMV TOA estimators and with the RDMV (Root Derivative Minimum Variance) TOA estimator presented in previous works. Root approaches provide higher resolution than grid search algorithms.