Fast RFI localization using virtual array in synthetic aperture interferometric radiometers

Radio frequency interference (RFI) has becoming a seriously limitation in the retrieval of geophysical parameters from the measurements of microwave radiometers. In this work, a novel RFI localization approach is presented here to improve the computationally complexity by using virtual arrays and direction of arrival (DOA) estimations techniques. The proposed RFI localization method utilizes the underlying rotational invariance among signal subspaces induced by the virtual array, which is expanded by the sparse array in synthetic aperture interferometric radiometer (SAIR). Estimating Signal Parameters via Rotational Invariance Techniques (ESPRIT) manifests remarkable performance and computational advantages in the test result over the proceeding approach like MUSIC without searching over parameter space.