The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Aug. 16, 2005
Filed:
Mar. 14, 2003
Frank N. Bauregger, Mountain View, CA (US);
Per Enge, Mountain View, CA (US);
Todd Walter, Mountain View, CA (US);
Dennis Akos, Palo Alto, CA (US);
Frank N. Bauregger, Mountain View, CA (US);
Per Enge, Mountain View, CA (US);
Todd Walter, Mountain View, CA (US);
Dennis Akos, Palo Alto, CA (US);
The Board of Trustees of the Leland Stanford Junior University, Stanford, CA (US);
Abstract
Method and apparatus for reducing radio frequency interference (RFI) using a dual-element patch antenna [The antenna possesses two antenna elements [having distinct radiation patterns. Either element may be independently selected using a DC bias voltage. Diodes [connected to the elements serve to disable one element when the other is selected. In one selected mode, a nominal radiation pattern provides a broad, hemispherical shaped sensitivity that is designed for acquiring and tracking all navigation satellites above the horizon. This nominal radiation pattern, however, is susceptible to interference that is present near or below the horizon. The second selectable radiation pattern of the dual-element antenna has comparatively higher gain toward zenith, and lower gain at and below the horizon to mitigate interference. This combination of features is packaged in a single antenna unit that can be a direct replacement for existing antennas. The dual-element antenna unit has a low vertical profile and is suitable for mounting on high-speed moving vehicles.