Near field imaging of subsurface targets using active arrays and elastic waves

This paper presents a time-reversal based approach for detecting the positions of subsurface passive targets like landmines. The measurements are made by using sources and sensors placed on the surface. The imaging algorithm uses the seismic waves reflected from the targets, and measured on the surface. A time-reversal based algorithm is used, which utilizes the possible link between the time-reversal matrix and the covariance matrix used in standard array processing. It is shown that the time-reversal matrix can be used to estimate the near field DOA and range parameters using a 2D MUSIC approach.