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In this study the polarization scattering matrices (PSM) of individual scatterers from a complex tactical ground target were measured as a function of look angle. Due to the potential value of PSMs in studies of automatic target recognition, a fully polarimetric, three-dimensional spot scanning radar modeling system was developed at 1 .56 THz to study the W-band scattering feature behavior from 1/16th scale models of targets. Scattering centers are isolated and coherently measured to determine the PSMs. Scatterers of varying complexity from a tactical target were measured and analyzed, including well-defmed fundamental odd and even bounce scatterers that maintain the exact normalized PSM with varied look angle, scatterers with varying cross-and co-pol terms, and combination scatterers. Maps defining the behavior of the position and PSM activity over varying look angle are likely to be unique to each target and could possibly represent exploitable features for ATR.The high-resolution spot scanning radar system transceiver uses a high-stability, narrow-band optically pumped far infrared laser and implements laser/microwave sideband generation. The measurement system is a heterodyned, fully polarimetric, three-dimensional imaging system, using raster scanning and frequency chirping to obtain the 3D image. The effect of mapping the 3D polarimetric scattering center data into range/cross-range ISAR imagery is demonstrated. The mapping showed considerable promise for retaining consistency over varying look angles, and the corresponding ISAR imagery demonstrated similar characteristics. The results were then analyzed in linear polarization and circular polarization bases for possible manipulations for the purpose of a simple ATR. A method utilizing the properties of two circular polarization receive states is demonstrated and its performance analyzed.

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