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:
Nov. 19, 1991
Filed:
Apr. 18, 1991
Clifford D Leitch, Coral Springs, FL (US);
Motorola, Inc., Schaumburg, IL (US);
Abstract
A transmitter, with an inphase input for receiving an inphase baseband input signal, and a quadrature input for receiving a quadrature baseband input signal, comprises a modulator, coupled to the inphase and quadrature inputs, for modulating the inphase and quadrature baseband signals to provide a modulated radio-frequency signal and a linear amplifier, coupled to the modulator, for amplifying the modulated radio-frequency signal to produce an output signal. Oscillation detector means are coupled to receive the output signal, for detecting oscillation, and for producing an error signal as a result of the oscillation. The transmitter also comprises means for reducing the open loop gain of the feedback loop, disposed between the inphase and quadrature inputs and the modulator. The means for reducing the open loop gain reduces the open loop gain of the transmitter to less than one, in response to the error signal.