초록 ▼

An omni directional coverage multibeam antenna relief on a ground surface having simple conical shapes to provide beam steering is disclosed. One advantage of such a system is that the projected area is always constant and broadside to the intended direction resulting in limited scan loss effects. I

An omni directional coverage multibeam antenna relief on a ground surface having simple conical shapes to provide beam steering is disclosed. One advantage of such a system is that the projected area is always constant and broadside to the intended direction resulting in limited scan loss effects. In the case of a cylinder as the conical shape, z-axis symmetry provides a constant antenna aperture projection in any azimuthal direction. Using this geometry, high level, side lobes are reduced considerably because of the natural aperture tapering from dispersion effects. Coverage area and power can be controlled by changing the ground surface angle and by selectively activating different antenna beam positions around the circumference of the ground surface, and by selectively changing the phase relationship between a given set of antenna beams. Likewise, beam down-tilt may be electrically realized by providing a phase differentiated signal to different antenna sections associated with an antenna beam. Furthermore, modular circuitry may be utilized to provide different beam widths from a single antenna structure design.

대표청구항 ▼

[ What is claimed is:] [1.] A multibeam antenna system having a plurality of radiating structures, said antenna system comprising:signal providing means, selected from a plurality of signal providing means, for accepting an input signal and providing said input signal to a preselected group of said

[ What is claimed is:] [1.] A multibeam antenna system having a plurality of radiating structures, said antenna system comprising:signal providing means, selected from a plurality of signal providing means, for accepting an input signal and providing said input signal to a preselected group of said radiating structures, said group of radiating structures selected such that excitation by said input signal radiates a signal from said antenna system combining to form a wave front having a predetermined beam width, wherein ones of said sigmal providing means provide said input signal to different preselected groups of said radiating structures to thereby provide different predetermined beam widths and other ones of said signal providing means provide said input singal to same preselected groups of said radiating structures to thereby provide same predetermined beam widths; andmeans for removably accepting different ones of said plurality of signal providing means in said antenna system, wherein said plurality of radiating structures are provided in a predetermined array configuration adapted to removably accept said different ones of said plurality of signal providing means without altering said predetermined array configuration.