Discrimination of the active submerged/bottom target based on the total scintillation index

Abstract

A variant of the traditional modal scintillation index is proposed for the discrimination of the active submerged/bottom target in a shallow water waveguide. Referred to the scintillation index applied in the passive surface/submerged target discrimination, the mathematical definitions of the modulated scintillation index (MSIm) and the total scintillation index (TSI) are introduced for active targets, where the mode excitations due to the target depth modulation exhibit a submerged or bottom dependent signature that can be exploited to statistically separate submerged and bottom targets. Simulations are presented for both an ideal sound speed profile as well as a typical sound speed profile of a downward refraction in shallow water environment. The approach based on the proposed TSI can provide a robust alternative to matched field processing for the problem of binary active submerged/bottom target classification.