A high power and highly efficient multi-band power amplifier for mobile terminals

This paper presents a highly efficient multi-band heterojunction bipolar transistor power amplifier (PA) employing reconfigurable matching networks (MNs). The MN consists of field effect transistor switches and achieves the desired matching condition in the target frequency band by controlling the on/off status of switches. The fabricated reconfigurable PA has 3-stage and operates in 9 bands from 0.7 to 2.5 GHz, i.e., 0.7, 0.8, 0.9, 1.4, 1.7, 1.8, 1.9, 2.3, and 2.5-GHz bands, with over a 30 dB gain. It also achieves an output power of greater than 34 dBm and a power added efficiency of over 40% at the supply voltage of 3.5 V in each operating band.