Spectral diversity for ground clutter mitigation in forward-looking GPR

The operational constraints associated with a forward-looking ground-penetrating radar (GPR) limit the ability of the radar to resolve targets in the dimension orthogonal to the ground. As such, detection performance of buried targets is greatly inhibited by the relatively large response due to surface clutter. The response of buried targets differs from surface targets due to the interaction at the boundary and propagation through the ground media. The electromagnetic properties of the media, interrogation frequency, depth of buried target, and location of the target with respect to the the sensing platform all contribute to the shape, position, and magnitude of the point spread function (PSF). The standard FLGPR scenario produces a wide-band data set collected over a fixed set of observation points. By observing the shape, position, and amplitude behavior of the PSF as a function of frequency and sensor position (time), energy resulting from surface clutter can be separated from energy resulting from buried targets. There are many possible ways beyond conventional image resolution that might be exploited to improve distinction between buried targets and surface clutter. This investigation exploits the frequency dependence of buried targets compared to surface targets using a set of sub-banded images.