Foliage Penetrating Synthetic Aperture Radar
Lockheed Martin has developed a radar that strips away foliage and allows you to track targets under the treetops.
the dual-band FOPEN system uses low-frequency radio waves to achieve high-resolution penetration of concealed areas –– natural ones like leaves or wood, or man-made camouflage –– with relatively low loss in signal strength at ranges of up to 60 km