The imaging method and sampling scheme of rotation scanning interferometric radiometer

Rotation scanning interferometric radiometer is a kind of new proposed time shared imaging concept for purpose of further decreasing the hardware complexity and increasing the spatial resolution. The main problem need to be solved is the image reconstruction from the rotation sampling visibilities. In this study we develop a Pseudo-Polar FFT algorithm that suitable for dealing with the polar sampling grid data of rotation scanning system. It takes pseudo polar grid as the conversion destination instead of traditional Cartesian rectangular grid before the Fourier inversion. The involved effective 1D interpolations and 1D-FFT routines in this imaging algorithm guaranteed a high accuracy and computational efficiency. Moreover we analyzed the associated rotation sampling scheme such as the antenna array arrangement and rotation sampling interval which have great effects on the reconstruction results. Numerical simulations are present for validating the superiority of this new imaging algorithm. Simulation results also indicated that the non-redundant plane antenna array with good linearity is the prefer array arrangement for rotation scanning system.