Patent ID: 8854248

Claim:
A method performed by a computing device for detecting presence of a subsurface object in a medium, the method comprising: for each of a plurality of down-track locations, acquiring return signals at receivers from signals emitted by transmitters into the medium, the transmitters and receivers operating in a multistatic mode; pre-processing the return signals to suppress effects of extraneous signals; for each down-track location, generating by the computing device a real aperture radar image from the pre-processed return signals for that down-track location; for each down-track location, generating by the computing device a synthetic aperture radar image from the real aperture radar images of that down-track location and adjacent down-track locations; post-processing the synthetic aperture radar images to separate objects in the foreground from clutter and medium in the background by filtering out effects of clutter followed by restoring spots within the filtered images to their pre-filtered values; for each down-track location, generating a statistic based on energy of a restored spot within the filtered image for that down-track location; and identifying down-track locations with peaks in the generated statistics; and upon identifying a down-track location with a peak, indicating the presence of a subsurface object at that down-track location.