Low Complexity Toa Estimation for Wireless Location

Positioning estimation based on Time Of Arrival (TOA) estimation needs high accurate first arrival detector. Highresolution TOA estimators based on Minimum Variance (MV) and Normalized Minimum Variance (NMV) provide an accurate estimation of the first arrival even in high multipath environments at the expenses of a high computational cost. The aim of this paper is to reduce the computational burden of high resolution TOA estimators. First, reduced complexity MV and NMV implementations based on the FFT are presented. Next, polynomial root versions of both estimators are proposed yielding an improvement in positioning accuracy. Finally, a near TOA Maximum Likelihood (ML) estimator is proposed providing a good trade off between complexity and accuracy.