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. 23, 1976
Filed:
Feb. 27, 1975
Francis G Overbury, Cuffley, EN;
Paul Barton, Bishops Stortford, EN;
Kevin M Kelly, Sawbridgeworth, EN;
International Standard Electric Corporation, New York, NY (US);
Abstract
A signal processing arrangement, particularly for Doppler ILS, giving complete scanning verification and tracking filter operation. Two commutated filters are driven by two voltage controlled oscillators whose roles are interchangeable. One filter is used solely for information signal tracking and the other solely for scanning. If the true signal is being tracked, the peak output from the scanning filter corresponds in amplitude and frequency to this signal and occurs at the same time as the frequency coincidence of the two oscillators. If the incorrect signal is being tracked, there is non-correspondance between the peak output and the signal being tracked. This is detected and the roles of the oscillators are interchanged, causing the oscillator which was scanning to reside on the correct signal and the other oscillator to adopt the scan program.