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:
Dec. 19, 2000
Filed:
Nov. 06, 1998
Eric Frank Vannerson, Phoenix, AZ (US);
Wm Keith Baker, Belfountain, CA;
Sotos Michael Theodoulou, Bramalea, CA;
Xerox Corporation, Stamford, CT (US);
Abstract
A device for providing an RF signal burst to an external load includes a voltage-controlled oscillator to generate a drive signal having a frequency f.sub.VCO fixed by an oscillator control signal. An RF driver stage coupled to the external load receives the drive signal and generates an RF signal burst in response to the drive signal. A current transformer coupled between the RF driver stage and the external load senses the current in the RF driver stage and generates a reference current having the same phase as the sensed current. A phase detector receives the reference current along with the drive signal and generates a phase detection signal that provides a measure of the phase of the current in the RF driver stage with respect to the drive signal. The phase detection signal can be used to adjust the oscillator control signal to drive the oscillator frequency to a desired value.