Patent ID: 6803818
Filing Date: 2004-10-12
Classification: H03G

Abstract:
An amplifier circuit for use in a wireless transmission system capable of operating in one of at least two different modulation modes, each of the modulation modes having a corresponding desired data rate associated therewith, the amplifier circuit comprising:an attenuator configurable for receiving an input signal associated with one of the at least two modulation modes of the transmission system, the attenuator being operative to control an attenuation of the input signal; an amplifier coupled to the attenuator, the amplifier receiving the attenuated input signal and generating an amplified output signal; at least one power detector configurable to independently detect at least a portion of an incidental wave and a reflected wave corresponding to the amplified output signal and to generate first and second signals representative of the detected incidental and reflected waves, respectively; and a controller operatively coupled between the at least one power detector and the attenuator in a feedback configuration, the controller controlling at least one of the attenuation of the input signal and an amplification of the input signal as a function of the first and second signals from the power detector and being operative to control a linearity of the amplifier such that the desired data rate of the received input signal is substantially maintained for the corresponding modulation mode of the transmission system; whereby the output signal of the amplifier circuit is maintained at a substantially constant power level.