Understanding radar signals in a highly heterogeneous clutter environment

Ground-penetrating radar (GPR) systems operate very often in environments with highly heterogeneous clutter sources and typically low signal-to- clutter ratios (SCRs). These clutter sources are generally divided, according to their origin, as surface and subsurface clutters. Surface clutter is related, particularly, to the reflection produced by the air-soil interface and also by objects located on the surface near the antennas. Subsurface clutter can be originated from all kinds of soil inhomogeneities and by other objects present in the targeted area. Besides dealing with low SCRs, GPR systems have generally limited bandwidth due to soil attenuation. This implies that the obtained resolution is usually not enough to differentiate between targets and clutter sources with similar characteristics. In this chapter, we will show examples as to how clutter affects GPR data and how multistatic acquisitions and polarimetry can be applied in GPR to improve detection and classification attempting to compensate these limitations in resolution and SCR.