Methods for source localization from time difference of arrival measurements and their performance improvement in ill-conditioned cases

Çelenk, Nusret
Estimating the location of a radiating source is crucial in a wide variety of fields, such as military applications, navigation systems and geophysics. In such fields, power and cost limitations, requirement of remaining undetected or the nature of the problem may necessitate passive localization techniques. One of such techniques is time difference of arrival (TDOA) based source localization. In this thesis, TDOA based closed-form source localization methods are studied. An extensive overview of the available methods is given. Some modifications are made on the existing methods to solve some ambiguities, reduce computational cost and increase estimation performance. Moreover, sensor and source distribution scenarios causing the problem to be ill-conditioned are analyzed. A new method robust to ill-conditioned cases, namely efficient constrained weighted least squares with coordinate separation (ECWLS-CS) is proposed. Existing methods and the proposed one are implemented in the same framework and compared under certain scenarios.


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Citation Formats
N. Çelenk, “Methods for source localization from time difference of arrival measurements and their performance improvement in ill-conditioned cases,” M.S. - Master of Science, Middle East Technical University, 2018.