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arXiv · 1712.07148

Direct Positioning with Channel Database Assistance

Laurence Mailaender·Arkady Molev-Shteiman·Xiao-Feng Qi
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Abstract

When we have knowledge of the positions of nearby walls and buildings, estimating the source location becomes a very efficient way of characterizing and estimating a radio channel. We consider localization performance with and without this knowledge. We treat the multipath channel as a set of "virtual receivers" whose positions can be pre-stored in a channel database. Using wall knowledge, we develop a generalized MUSIC algorithm that treats the wall reflection parameter as a nuisance variable. We compare this to a classic MVDR direct positioning algorithm that lacks wall knowledge. In a simple scenario, we find that lack of wall knowledge can increase location error by 7-100x, depending on the number of antennas, SNR, and true reflection parameter. Interestingly, as the number of antennas increases, the value of wall knowledge decreases.

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Laurence Mailaender, Arkady Molev-Shteiman, Xiao-Feng Qi. 2017-12-19. Direct Positioning with Channel Database Assistance. https://arxiv.org/abs/1712.07148

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