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:
Aug. 22, 2000
Filed:
Apr. 30, 1998
Jean-Luc de Gouy, Briis sous Forges, FR;
Pascal Gabet, Chaville, FR;
Thomson-CSF, Paris, FR;
Abstract
Present-day single or multiple fractional phase-locked loop frequency synthesizers are not phase coherent for they use a digital accumulator modulo a number P with a variable increment K, whose state is a function of the history of the change in values that have been imposed on the increment. This lack of phase coherence rules out the use of these synthesizers in certain fields such as that of Doppler radars. A novel type of single or multiple fractional phase-locked loop frequency synthesizer that is coherent in phase is proposed herein. This type of synthesizer comprises one or more counters with an increment of one, having their rate set by the reference oscillator of the synthesizer and being used in phase memories to enable changes in the increment or increments following a change in the fractional division ratio at instants that are synchronous with the reference oscillator.