A receiver-autonomous non-cryptographic civil GPS anti-spoofing technique called the vestigial signal defense (VSD) is defined and evaluated. This technique monitors distortions in the complex correlation domain to detect spoofing attacks. Multipath and spoofing interference models are developed to illustrate the challenge of distinguishing the two phenomena in the VSD. A campaign to collect spoofing and multipath data is described, which specific candidate VSD techniques can be tested against. Test results indicate that the presence of multipath complicated the setting of an appropriate spoofing detection threshold.

Cite and download the paper:
Wesson, K.D., D.P. Shepard, J.A. Bhatti, and T.E. Humphreys, "An Evaluation of the Vestigial Signal Defense for Civil GPS Anti-Spoofing," Proceedings of ION GNSS, Portland, Oregon, 2011.

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