Signal processing of laser-Doppler vibrometer output for mine detection

Sound waves from a powerful loudspeaker can excite a certain type of vibration of the surface of the ground when a mine is present and near the surface. In turn, a laser-Doppler vibrometer can be employed to acquire information about the surface vibrations. In particular, the portion of the ground surface that is vibrating has the shape of the projection of the mine onto the surface. This paper discusses a method based on Bayesian probability theory for processing laser- Doppler vibrometer data to infer the periphery of any surface vibration pattern. Difficulties with using a phase- lock loop in determining a surface map are also discussed.