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arXiv · 2007.12662

Generalized likelihood ratio test detector for a modified replacement model target in a multivariate t-distributed background

James Theiler
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Abstract

A closed-form expression is derived for the generalized likelihood ratio test (GLRT) detector of a subpixel target in a multispectral image whose area and brightness are both unknown. This expression extends a previous result (which assumed a Gaussian background distribution) to a fatter tailed elliptically-contoured (EC) multivariate t-distributed background. Numerical experiments with simulated data indicate that the EC-based detector outperforms the simpler Gaussian-based detectors, and that the relative performance of the new detector, compared to other EC-based detectors, depends on the regime of target strength and background occlusion.

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James Theiler. 2020-07-24. Generalized likelihood ratio test detector for a modified replacement model target in a multivariate t-distributed background. https://arxiv.org/abs/2007.12662

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