Patent ID: 6492867
Filing Date: 2002-12-10
Classification: H03F,H03G,H04L

Abstract:
A method for improving the efficiency and the dynamic range of a power amplifier operated with signals having a large peak-to-average ratio, comprising:a) providing an auxiliary amplifying circuitry of a Doherty configuration and a main amplifier, said main amplifier and said auxiliary amplifying circuitry comprising said power amplifier; b) determining a reference level, above which at least a portion of the magnitude of an input signal being a modulated signal that is input to said power amplifier, or a baseband waveform that is used to generate said modulated signal, is defined as an excess input signal; c) continuously sampling said magnitude of said input signal, for detecting an excess input signal; d) if no excess input signal is detected, supplying a constant level of operating voltage to said power amplifier, said constant level of operating voltage being sufficient to effectively amplify input signals having a magnitude below said reference level; and e) whenever the excess signal is detected, concurrently supplying a variable level of operating voltage to said power amplifier, said level of operating voltage essentially tracking the magnitude of said excess input signal with use of analog circuitry, thereby supplying, to said power amplifier, a variable increased level of operating voltage being sufficient to effectively amplify input signals having a magnitude above said reference level.