A Wide-Band High-Gain Doherty Power Amplifier With Class-AB HEMT Amplifiers

Abstract

In this paper, an attempt has been made to design a Doherty power amplifier (DPA) with high-gain and wide-band. For this purpose, two peak amplifiers are used to improve the performance of the main amplifier. Main and auxiliary amplifiers with the same structure to the class-AB type and by using micro-strip lines in place of input/output and load matching networks, transmission lines and inductors of drain and gate, that minimize the losses in the DPA. The current DPA is implemented with GaN_HEMT_CLF1G0530_100v transistor and Rogers4003 substrate, which for 1GHz frequency in 0.5-1.5GHz bandwidth will be able to be at P-1dB point (this point, input power as 30dBm and output power as 47.98dBm) increase Drain efficiency and Power added efficiency (PAE) to 81.95% and 80.73%, respectively. The DPA helps to expand the back-off region and extend the linearity region, so the Peak to average power ratio (PAPR) will be 5.21dB and the Adjacent channel power ratio (ACPR) as 58.7dBc. A gain of 17.06-17.92dB was also obtained, which is significant compared to the results of similar samples.