Conformal transformation for efficient ROOT-TOA estimation

Wireless location based on TOA (time-of-arrival) requires an accurate estimation of the first time delay. In this context, polynomial rooting techniques can provide an accurate estimation of the first arrival even in adverse multipath scenarios and when the direct path is highly attenuated. In general, these methods imply finding the roots of a complex polynomial. The aim of this paper is to present a conformal mapping that circumvents this problem, transforming it into a root search of a real polynomial with the resulting decrease in computational load.