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. 22, 1993
Filed:
Oct. 24, 1991
William J Keane, San Jose, CA (US);
Cristopher F Schiebold, Palo Alto, CA (US);
Dirk M Hoekstra, Los Altos, CA (US);
Other;
Abstract
A YIG notch filter using full RF coupling loops and having a notch filter center frequency tunable as high as 18 GHz comprising a plurality of undoped YIG spheres of much smaller volume than used in the prior art and linearly arranged in a air gap. The spheres are suspended in cavities in a nonmagnetic block which are spaced much more closely than in the prior art. The 50 ohm stripline impedance inverters formed on a substrate and connecting the RF coupling loops of the spheres used in the prior art are eliminated. The quarter-wavelength impedance inverter function necessary to fabricate a notch filter is implemented by using the RF coupling loops themselves and measuring the distance from centerline to centerline of adjacent RF coupling loops. Twin insulated wires with up to one diameter separation for the RF coupling loops are preferred with the wires soldered together between the spheres.