Comparison between Rectangular and Hexagonal Synthetic Apertures for Radar Imaging

In this paper, rectangular and hexagonal spatial distributions are analyzed in order to compare their usability to form the aperture of a nearfield Synthetic Aperture Radar (SAR) using the backprojection algorithm. The algorithm itself and its computational efficiency are in general independent from the antenna grid. It is shown that this approach is suitable to reduce the maximum side lobe level by 12.5% with nearly no effect on the main lobe width, if the spacing between the antenna positions is chosen in the right way. Additionally this paper presents radar measurement results at 144 GHz that support the theoretical investigations.