Amplitude weighting of irregular planar arrays: Minimising near-in and intermediate sidelobes

Amplitude tapering can be employed for phased array systems in order to reduce the level of coherent sidelobes in a Nyquist sampled array. Whilst this is true for both regular and irregular geometries, the latter, which may be implemented for under-sampled regimes to avoid grating lobes, can benefit by a method of occupied area adjustment, in which the amplitude of each element depends on its distance from nearby elements as well as its position in the array as a whole. Herein, we propose methods for both 1D and 2D arrays using a number of area adjustment techniques, namely Voronoi cell and nearest neighbour, to further reduce the near-in and intermediate sidelobes. As an example, we explore the potential use of this method for the SKA-LOW telescope.