Spatial beamformer weighting sets for circular array STAP

An experimental, circular, electronically scanned array is being fabricated by Raytheon as part of the Office of Naval Research sponsored UHF Electronically Scanned Array (UESA) program. Space-time adaptive processing (STAP) techniques applied to circular arrays are of particular interest on this project. STAP refers to adaptive nulling techniques in the angle Doppler domain to place nulls in the direction of clutter or jammers. Traditionally STAP techniques have been applied to linear arrays and, until recently much less attention has been directed at employing STAP techniques for circular arrays. In this paper we explore the spatial beamformer weights (or antenna distribution) that form an interference-free pattern in the presence of multiple jammers for circular arrays of directional elements. The goal is to create patterns that have high directivity, low sidelobes, yet multiple nulls in specified angular directions, This information may be used in pre- or post-processing algorithms by providing information of the spatial beamformer weights between an optimum linear STAP processor and a circular array