The Design and Verification of a Hierarchical Wideband Beamforming System for SKA MFAA

The SKA (Square Kilometer Array) midfrequency aperture array (MFAA) is one of the representatives of the next-generation digital array that raises the unique challenges to realize a feasible and affordable large array with sufficient beamforming flexibility. This paper presents the design and verification of a hierarchical beamforming architecture for MFAA. The novel hierarchical beamforming architecture adopts a true-delay line based beamforming and switching design. Combined with a dense-pack Vivaldi antenna front-end, the system is able to cover the 90° of the sky with 2 to 16 output beams based on various processing capability.