Non-periodic arrays for radio-astronomy applications

The exploitation of non-periodic antenna arrays for next-generation radio-telescopes is evaluated in the present work. More precisely, the radiation properties and the mutual coupling effects in such structures are studied. A special-purpose Method-of-Moments (MoM) simulation technique allows us to obtain all the Embedded Element Patterns (EEP) and the array impedance matrix, while estimating the effects of mutual coupling in very large arrays. The level of averaging of mutual-coupling effects is analyzed in terms of array patterns and the more difficult case of deterministic nulling in presence of mutual coupling is exposed.