A 5W class-AB power amplifier based on a GaN HEMT for LTE communication band

In this paper, the design and characterization of a GaN HEMT based class-AB power amplifier (PA) operating in LTE communication band (1.9-2.5 GHz) are presented. A model-based design procedure is adopted. Source and load impedances for optimum linearity, power and efficiency are extracted through source- and load-pull simulation. The implemented PA shows excellent performance on the whole frequency band from both the efficiency and linearity points of view. It provides a saturated output power of 36.9 dBm and a gain of 19dB at the design frequency of 2.3 GHz, over a 600 MHz bandwidth. Measurements report a saturated power-added efficiency (PAE) of 68 % and a PAE at 1dB compression of 54.3 %. System level characterization with a 7 MHz-bandwidth QAM-256 input signal is also carried out on the fabricated PA.