Selectable beam antenna

Abstract

A selectable beam antenna of generally linear, polygonal, planar or polyhedral form, able to operate at microwave and millimetre wave frequencies, and constructed from associated networks that incorporate radio frequency switches, time delays and amplitude weights positioned within a set of interleaved transmission, lines or waveguides to simultaneously perform both beam-forming and beam selection operations, which selectable beam antenna comprises: (i) a single RP antenna port connected to a 1-to-N corporate feed means, where N is greater than or equal to 2; (ii) a EF switch network means of N/q multi-pole-multi-throw radio frequency switch means (qPMT) connected to the corporate feed means; (iii) a RF distribution means of N×M singularly or multiply interleaved lines arranged so as to have approximately equal transmission length connected to the switch means, where M is the number of throws associated with each radio frequency switch means (qPMT); (iv) an antenna launch means of M×M interleaved antenna element sub-groups of S linear or planar elements, where S is greater than or equal to one, σorporately connected to the distribution means and arranged to closely follow at sub-wavelength intervals a closed are or segment of a closed surface; and (v) an overall electronic control means to set all radio frequency switches in such a way to select, to time delay and to amplitude weight the activated interleaved antenna launch elements and thus generate one of the possible directed, antenna beams.