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:
Mar. 03, 1987
Filed:
Aug. 21, 1984
Charles C Counselman, III, Belmont, MA (US);
Donald H Steinbrecher, Brookline, MA (US);
Western Geophysical Co., Houston, TX (US);
Abstract
A circularly polarized microwave radio antenna which is constructed so that its phase center can be very easily and very accurately positioned with respect to a marker point over which the antenna is placed is disclosed. The antenna includes a ground plane, antenna elements in a common plane parallel thereto and supported by a perpendicular center post, separate feed lines for each element and a combining network all positioned symmetrically about an axial bore in the center post so that the phase center of the antenna is on the axis of the center post at the intersection with the upper surface of the ground plane. A graduated rod may be positioned in the bore to align the antenna with the marker point. The antenna is especially useful in microwave radio interferometry systems for measuring relative position vectors between survey marks on the ground using radio frequency signals transmitted from earth orbiting satellites but may be used in any application where accurate positioning of an antenna's phase center relative to a reference point is desired or required. The antenna can be easily reproduced with substantially identical electrical and mechanical characteristics.