Backscatter from a corner reflector close to a two-antenna radar system

The return signal from a corner reflector placed close to a two-antenna radar system was investigated. Near field effects and geometrical effects due to antenna separation and variable pointing of the antennas were studied. Calculations were compared with experiments performed with a 94 GHz radar. The purely geometrical effects of antenna separation and focusing are more important than near field effects. The antenna separation effect disappears with increasing range; the effect of intersecting antenna lobes persists. Near field effects are most important in a radar with a single antenna. For a 94 GHz radar with an antenna diameter of 0.5 m, near field effects are apparent at ranges 100 m.