Subspace smearing and interference mitigation with array radio telescopes

Abstract

Array radio telescopes are suitable for the implementation of spatial filters. These filters present the advantage of canceling potential radio frequency interference (RFI) while recovering uncorrupted Time-Frequency data, of interest to astronomers. Although information regarding the sources of RFI can be a priori known or reliably inferred, the complexity of radio telescope systems randomizes the formulation of the subspace spanned by the RFI due to a lack of calibration or characterization. This knowledge is however necessary for building an efficient spatial filter, and needs therefore to be estimated.