Sparse and Thinned Arrays for Multiple Beam Satellite Applications

In this paper some of the potentialities of aperiodic arrays for multiple beam satellite applications are discussed. Especially when their elements are uniformly fed, aperiodic arrays may be useful for reducing cost and complexity of direct radiating arrays for satellite multibeam applications. Playing with the aperiodicity, the number of elements can be reduced without changing the array aperture size while sidelobe and grating lobe levels can be optimised to deal with isolation constraints. Equal amplitude excitation of the elements in the transmit mode maximizes the antenna power efficiency since all the amplifiers operate at their most efficient working point. Moreover, the higher power required per amplifier, to keep a similar equivalent isotropically radiated power, favours the use of high-efficiency mini travelling tube amplifiers instead of solid state amplifiers. Grating lobes peak is reduced as well when the elements are positioned in one aperiodic lattice.