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:
Jan. 30, 1990
Filed:
Dec. 24, 1986
NEC Corporation, Tokyo, JP;
Abstract
A horn antenna for radiating or receiving a microwave is provided with a plurality of axially spaced radial fins fixedly mounted on the outer surface of the horn, which fins form a plurality of radial grooves and a front axial groove each having a depth of approximately equal to a quarter of a wavelength of the microwave. Those fins and grooves form a choke surface-wave structure which improves the radiation pattern and reduces undesired radiation and side lobe. A multimode horn arrangement for a higher frequency wave is employed for the horn so that two different frequency waves are efficiently radiated or received at a single horn antenna with a reduced side lobe and an excellent cross polarization characteristic.