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

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.

Design and Optimization of 2.1 mW ULP Doherty Power Amplifier with Interstage Capacitances Using 65 nm CMOS Technology

This research proposed the design and calculations of ultra-low power (ULP) Doherty power amplifier (PA) using 65 nm CMOS technology. Both the main and the peaking amplifiers are designed and optimized using equivalent lumped parameters and power combiner models. The operation has been performed in RF-nMOS subthreshold or triode region to achieve ultra-low power (ULP) and to improve the linearity of the overall power amplifier (PA). The novel design consumes a DC power of 2.1 mW, power-added efficiency (PAE) of 29.8%, operating at 2.4 GHz band, and output referred 1 dB compression point at 4.1dBm. The simulation results show a very good capability of drive current, high gain, and very low input and output insertion losses.