Experimental Characterization of Circular Polarization Selective Structures Using Linearly Single-Polarized Antennas

Abstract

We present a technique for performing high-accuracy measurements of the transmission and reflection properties in circular polarizations (CPs) of a test panel. Using linearly polarized antennas and measuring at four different antenna orientations, all with a relative rotation of 45°, an efficient normalization of each scattering component can be utilized. This method achieves a high signal-to-noise ratio in all normalized linear polarization components used to synthesize the CP scattering. Furthermore, a postprocessing scheme is introduced to compensate for measurement uncertainties due to antenna misalignments. The novel measurement and postprocessing techniques are utilized to characterize a manufactured wideband CP selective structure, both in transmission and reflection, and the measurement results are in excellent agreement with simulation results from commercial software. The repeatability of the measurement results is investigated, and the results are in the expected range in comparison with estimated measurement uncertainties.