Detection of subsurface rocks in sand of similar composition using a millimeter wave imaging system

The ability to image objects, whether natural or man made, beneath soil is extremely beneficial. The detection scenario becomes increasingly difficult when the object and the soil are composed of the same material, as in the detection of subsurface rocks. The feasibility of detecting rock in similar composition is explored. An active multi-spectral millimeter wave (mmW) imaging system operating from 90–140 GHz is used to detect lava rock buried beneath lava sand at various depths, up to a limit of 64 mm. The principal component analysis method was used in the data processing.