SOLVIT:A Reference-Free Source Localization Technique using Majorization Minimization

Abstract

We consider the problem of localizing the source using range and range-difference measurements. Both the problems are known to be non-convex and non-smooth, which makes it challenging to solve. In the case of range-difference measurements, most of the current positioning techniques choose a reference sensor, however the source positioning accuracy has been reported to be affected by this approach. In this paper, we localize the source from range-difference measurements without choosing a reference sensor. We develop an iterative algorithm to solve the range-difference problem using Majorization Minimization (MM) approach-in which we employ a novel upper bound and minimize it to get a closed form solution at every iteration. The proposed algorithm is referred to as SOLVIT: Source Localization Via an Iterative technique. We also solve the source localization problem based on range measurements and rederive the Standard Fixed Point (SFP) algorithm developed in [1] using the MM approach. By doing so, we show a less intricate way to prove the convergence of the SFP algorithm. Next, we show a computationally efficient way to implement SOLVIT. Various simulations and experiments were conducted to compare SOLVIT with the existing methods. Experiments were conducted in an anechoic chamber to localize an acoustic source. Simulations and experiments confirm that SOLVIT performs better than existing methods in terms of source positioning accuracy. Also, it was found that when compared to the existing methods, SOLVIT does not depend on the positioning of source and sensors to localize a source.