A novel dual-band balanced power amplifier (DBPA) using a pair of branch-line couplers with four arbitrary terminated resistances is designed in this paper. The DBPA operating at 2.02 GHz and 2.6 GHz consists of two identical single-stage class-AB PAs connected in parallel and two branch-line couplers for power division and combination. Due to the usage of branch-line couplers with four arbitrary terminated resistances, the load/source-pull impedance obtained by ADS (Advanced Design System) can be matched to an arbitrary real impedance which decreases the complexity of dual-band matching network of the DBPA. To demonstrate the proposed design, a prototype based on CREE's GaN HEMT CGH40010F is fabricated and measured. The simulated results exhibit 67.9% and 73.6% power-added efficiency (PAE) values with output power of 44.1 and 43.4 dBm at 2.02 GHz and 2.6 GHz, respectively.
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