Optimization Design of a Dual-Band Reconfigurable Power Amplifier Using Dual-mode Impedance Objective Function

To meet the requirements for wideband and high-efficiency operation of power amplifiers (PAs) in dual-band modes, a reconfigurable PA based on dual-mode impedance objective function is optimized and designed. The dual-band switching is achieved by having the microstrip line end open (Mode 1) and the microstrip line end-coupled with a capacitor to ground (Mode 2), and the output matching network is optimized to satisfy the impedance requirement at both switching modes using the proposed dual-mode impedance objective function. For verification, a dual-band reconfigurable PA operating in the 0.8-1.0 GHz and 2.1-2.3 GHz frequency bands is designed and fabricated. Measurement results show that the reconfigurable PA achieves an efficiency greater than 64% and a saturated output power greater than 39.5 dBm in 0.8-1.0 GHz. In 2.1-2.3 GHz, the efficiency is greater than 53% and the saturated output power is greater than 40 dBm. The PA exhibits good linearization performance across both frequency bands, meeting the multi-band operation requirements of future mobile communication systems.