초록 ▼

A hand-held antenna specifically for GPS applications is provided which includes a microstrip patch antenna having a ground board, a single radiating patch spaced from the ground board and a resonant cavity defined between the ground board and the single radiating patch. Feed points are provided, on

A hand-held antenna specifically for GPS applications is provided which includes a microstrip patch antenna having a ground board, a single radiating patch spaced from the ground board and a resonant cavity defined between the ground board and the single radiating patch. Feed points are provided, one in the geometrical center of the radiating patch, and one, two, or four equidistantly spaced from the central feed point and disposed at 90.degree. angular intervals. A feed network couples fundamental modes of excitation to the side feed points on the patch and a higher mode of excitation to the central feed point. Amplitude and phase controllers are provided in the feed network for amplitude and phase shifting between the fundamental and higher order modes of excitation in order to steer a spatial null in azimuth and elevation.

대표청구항 ▼

[ What is claimed is:] [1.]1. An antenna system, comprising:a patch antenna, including:a ground plane,a single radiating patch installed in spaced relationship to said ground plane and extending substantially parallel thereto,a dielectric filled resonant cavity located between said ground plane and

[ What is claimed is:] [1.]1. An antenna system, comprising:a patch antenna, including:a ground plane,a single radiating patch installed in spaced relationship to said ground plane and extending substantially parallel thereto,a dielectric filled resonant cavity located between said ground plane and said single radiating patch,a central feed point disposed at the geometric center of said single radiating patch, andat least one first side feed point on said single radiating patch disposed a predetermined distance from said central feed point; anda feed network, coupled to said central and said at least one first side feed point,said feed network including:a first path for coupling at least a first fundamental mode of excitation to said at least one first side feed point,a second path for coupling a higher order mode of excitation to said central feed point to generate a top-loaded monopole radiation pattern, andmeans for controlling an amplitude and phase relationship between said at least first fundamental mode of excitation and said higher order mode of excitation, thereby creating a radiation pattern of said patch antenna having a directionally adjustable spatial null.