NLOS Error Mitigation for TOA-Based Source Localization With Unknown Transmission Time

In this letter, we address the time-of-arrival-based localization problem using an asynchronous sensor network under non-line-of-sight conditions. We formulate a robust least square (RLS) problem to jointly estimate the source location and the transmission time. To tackle the problem that the unknowns in the RLS problem are coupled with each other, we decouple the coupled constraint as the second-order cone constraints by applying some inequalities, and then apply the standard second-order cone relaxation technique to obtain a convex second-order cone program. Simulation results verify the performance of the proposed method.