A Direct Approach to Separate Forward-Scattered Waves from the Direct Blast in Doppler Domain for Forward-Scattering Detection

Forward-scattered waves are often interfered with and overwhelmed by direct blasts when a submerged target crosses the source-receiver line. The approach named low Doppler analysis and recording gram (LODARGRAM) is developed to separate forward-scattered waves from direct blasts in the Doppler domain. This separation, which is based on the kinetic characteristic of the target and the procedure, is conducted using a sliding Blackman window combined with fast Fourier transform. The concept along with its application is validated using the data collected in a tank experiment. The moving target is recognized and identified by a tilt striation on LODARGRAM. Limitations of the LODARGRAM approach are also discussed.