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arXiv · 1407.5616

TW-TOA Based Positioning in the Presence of Clock Imperfections

Mohammad Reza Gholami·Sinan Gezici·Erik G. Ström
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Abstract

This paper studies the positioning problem based on two-way time-of-arrival (TW-TOA) measurements in asynchronous wireless sensor networks. Since the optimal estimator for this problem involves difficult nonconvex optimization, we propose two suboptimal estimators based on squared-range least squares and least absolute mean of residual errors. The former approach is formulated as a general trust region subproblem which can be solved exactly under mild conditions. The latter approach is formulated as a difference of convex functions programming (DCP), which can be solved using a concave-convex procedure. Simulation results illustrate the high performance of the proposed techniques, especially for the DCP approach.

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Mohammad Reza Gholami, Sinan Gezici, Erik G. Ström. 2014-07-19. TW-TOA Based Positioning in the Presence of Clock Imperfections. https://arxiv.org/abs/1407.5616

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