Fully polarimetric W-band ISAR imagery of scale-model tactical targets using a 1.56THz compact range

With the continuing interest in ATR, there is a need for high-resolution fully polarimetric data on tactical targets at all radar bands. Here we describe a newly developed system for acquiring W-band data with 1/16 scale models. The NGIC sponsored ERADS project capability for obtaining fully polarimetric ISAR imagery now extends from X to W band. The high-frequency terahertz compact radar range developed recently to measure single polarization return from scale models of tactical targets has been enhanced to collect fully polarimetric data. The 1.56THz transceiver uses two highstability optically pumped far-infrared lasers, microwave/laser Schottky diode side-band generation for frequency sweep, and a pair of Schottky diode receivers for coherent integration. Tactical targets may be measured in "free space" or on various ground terrain, which simulate different types of terrain. The results of recent polarimetric measurements on several tactical targets will be presented. Data collected using this compact range from a simulation target will also be compared with predictions from the XPatch computer code. In addition to conventional ISAR imaging the compact range is capable of imaging in both azimuth and elevation by collecting data and integrating it through a solid angle. Recent two-dimensional and three-dimensional measurements using this technique will be presented.