Abstract: An antenna system comprising an array of antenna elements, the array comprising a plurality of groups of antenna elements wherein each group comprises one or more antenna elements arranged in series, and wherein the system further comprises first phase-control means for performing the function of introducing respective phase-shifts to transmitted or received signals passed to or received from each of said groups to provide beamforming and second phase-control means for performing said function with respect to a sub-set of said groups. An antenna system of the invention allows two radar beam patterns having different spatial characteristics to be generated using a single antenna system. The invention also provides a radar system incorporating an antenna system of the invention.

Abstract: A phased array antenna (400) comprises a first array element (402) and second array element (404) and a dielectric separator (408). Each of the first and second array elements (402,404) is a detection element and or an emitter element. The dielectric separator (408) is located between the first and second array elements (402, 404) and within a path of an inter-element mutual coupling (IMC) signal between the first array element (402) and the second array element (404).