POLARIMETRIC BISTATIC MEASUREMENT FACILITY FOR POINT AND DISTRIBUTED TARGETS

A fully polarimetric bistatic-radar facility has been constructed at t he University of Michigan, to serve as a research tool for improved un derstanding of the nature of bistatic scattering for point and distrib uted targets. The facility is capable of operation at 10, 35, and 94 G Hz, but only the 10-GHz system will be described in this presentation. To meet both the size and design constraints both a horn antenna oper ating in the far-field, and a parabolic-dish antenna operating in a ne ar-field focused mode, are utilized. A newly developed bistatic-calibr ation technique, using a flat metal plate, is used to calibrate the fa cility. Validation results, using a hemisphere over a conducting metal plate, show that the facility is capable of characterizing the radar cross section of a point target to within +/-1 dB in magnitude and +/- 5 degrees in polarization phase difference over a wide range of bistat ic angles. Sample data for a point target and a distributed target are presented.