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arXiv · 2401.15619

A semidefinite programming approach for robust elliptic localization

Wenxin Xiong·Yuming Chen·Jiajun He·Zhang-Lei Shi·Keyuan Hu·Hing Cheung So·Chi-Sing Leung
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Abstract

This short communication addresses the problem of elliptic localization with outlier measurements. Outliers are prevalent in various location-enabled applications, and can significantly compromise the positioning performance if not adequately handled. Instead of following the common trend of using $M$-estimation or adjusting the conventional least squares formulation by integrating extra error variables, we take a different path. Specifically, we explore the worst-case robust approximation criterion to bolster resistance of the elliptic location estimator against outliers. From a geometric standpoint, our method boils down to pinpointing the Chebyshev center of a feasible set, which is defined by the available bistatic ranges with bounded measurement errors. For a practical approach to the associated min-max problem, we convert it into the convex optimization framework of semidefinite programming (SDP). Numerical simulations confirm that our SDP-based technique can outperform a number of existing elliptic localization schemes in terms of positioning accuracy in Gaussian mixture noise.

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Wenxin Xiong, Yuming Chen, Jiajun He, Zhang-Lei Shi, Keyuan Hu, Hing Cheung So, Chi-Sing Leung. 2024-01-28. A semidefinite programming approach for robust elliptic localization. https://arxiv.org/abs/2401.15619

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