A dual mode GaAs HBT power amplifier for LTE applications

In this paper, a dual mode GaAs HBT power amplifier for LTE band I applications is present. The amplifier is designed to operate from 1.92 GHz to 1.98 GHz with 28 dB of gain, enough to work with transmitter chips with relative low output power. The amplifier deliveries 28 dBm of linear power at 3.4 V supply to satisfy the linearity requirement for the LTE application. To improve the average efficiency of the amplifier, a new structure of dual mode is proposed. At the high power mode, the efficiency of the amplifier is 34% at 28 dBm of CW output power, and at the low power mode, the efficiency of that is 22% at 15 dBm output power.