A linear InGaP/GaAs HBT power amplifier for LTE B7 applications

This paper describes a highly linear InGaP/GaAs HBT power amplifier (PA) for LTE band 7 applications. By optimizing a bias point of the power stage and the driver stage and adjusting sweet-spot point of IMD3, the linearity of the PA can be improved. By the measurement results, the level of ACLR is below −46 dBc up to a 23.5 dBm output power. The fabricated InGaP/GaAs HBT PA has a gain of 29.5 dB, a P1dB of 31.5 dBm, and a PAE of 36% under 5 V supply voltage.