Exploiting forward scattering for detecting submerged proud/half-buried unexploded ordnance

Abstract

Laboratory underwater bistatic scattering measurements are reported for free, proud, and half-buried unexploded ordnances for 0° and 90° source angles. Forward echoes are larger than backscattered returns, and half burial significantly decreases the latter but not the former. Results agree with analytic predictions borrowed from radar. The forward echo and source signal are separated by measurements made with and without the target, a method not possible in a target search. For this, a method is described that uses knowledge of the source location and the hyperbolic character in time-cross range of the signals received at points along a line.