METHOD AND APPARATUS FOR IMPROVING EFFICIENCY OF HIGH-POWER LINEAR AMPLIFIER

摘要

Disclosed is a method and apparatus for improving thermal efficiency and fie ld reliability of a linear power amplifier of a communicating system. In as illustrative embodiment, the communication system operates in a half-duplex mode sad a transistor control terminal (e.g., gate) of the amplifier is bias ed at a first bias voltage during transmit intervals of the half-duplex mode. The control terminal is biased a t a second bias voltage differ from the first bias voltage during receive intervals. The second bias voltage is sufficient to reduce idle currents in the amplifier during the receive intervals, thereby improving thermal efficiency of the amplifier. Also diseased is a base station including a base station controller, a variable bias control circuit and a linear power amplifier. The variable bias control circuit operates under the control of the base station controller to supply a variable bias voltage to the amplifier. Thermal efficiency of the amplifier is improved by reducin g idle currents via appropriate bias voltage control during a weak signal transmitting mode and/or during receive intervals of a half-duplex operating mode.