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. 28, 1990
Filed:
Sep. 12, 1989
Hilmer I Swanson, Quincy, IL (US);
Harris Corporation, Melbourne, FL (US);
Abstract
An RF amplitude modulated amplifier system is presented incorporating a plurality of RF amplifiers which are compensated for unwanted phase modulation. The system includes a common RF driver for supplying a common RF driver signal. A plurality of actuatable RF amplifiers are provided with each having an input circuit for receiving the common RF drive signal. Each amplifier has a fully on condition for amplifying the common drive signal to provide an amplified RF signal, and a fully off condition. Each of these RF amplifiers exhibits a characteristic in that its input circuit has an input impedance which is greater when fully on than that when fully off, thereby tending to present unwanted phase modulation of the plurality of RF amplifiers. One or more of the RF amplifiers are selectively turned fully on in dependence upon the magnitude of an input signal. The amplified RF signals provided by the RF amplifiers that are turned on are combined so as to provide a combined signal which is amplitude modulated in accordance with the magnitude of the input signal. Circuitry is provided for selectively adding a compensating impedance to the input circuit of each of the RF amplifiers that is not actuated to be fully on. This serves to compensate for any unwanted phase modulation of the plurality of RF amplifiers.