An Iteratively closed-form solution to passive localization by a single moving observer using TOA only with unknown SRI

An iteratively closed-form solution to passive localization by a single moving observer only using time of arrival (TOA) only with unknown signal repetition interval (SRI) is investigated in this paper. The proposed algorithm includes three main stages. In the first stage the initial value of SRI and SRI integer are obtained by neglecting the signal propagation delay in the TOA model. In the second stage the emitter position is obtained by a closed-form solution using the estimated SRI and SRI integer. An improved SRI is obtained by a least square estimator (LSE) using the TOA compensated by the estimated emitter position in the third stage. The second and third stage are repeated to achieve higher precision. The effectiveness of the algorithm is verified by simulation.