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:
Jun. 20, 1995
Filed:
Aug. 19, 1994
Elio A Mariani, Hamilton Square, NJ (US);
The United States of America as represented by the Secretary of the Army, Washington, DC (US);
Abstract
A planar preselector filter with tunable narrowband excision composed of a errite substrate having a microstrip line with a fixed-tuned bandpass filter on one surface and a plurality of slotline resonators etched in a ground plane on an opposing surface. The fixed tuned bandpass filter is composed of short resonant elements of microstrip, having a length that is one-half the guide wavelength at the center frequency of its passband. The slotline resonators are positioned on the opposing surface of the substrate such that it suppresses or excises a predetermined narrowband of frequencies within the passband of the fixed-tuned bandpass filter. Moreover, the center frequency of the narrowband excision is varied by applying a tunable magnetic bias field of a predetermined strength across the ferrite substrate.