Concurrent tri-band power amplifier based on novel tri-band impedance transformer

In this paper, we present a concurrent tri-band power amplifier by using a tri-band matching network synthesis method. At the package plane, a cross-type impedance transformer and susceptance matching network are placed in parallel to realize the desired admittance at three independent frequencies. Design equations of the different possible topologies are present based on ABCD-parameters. Then, the proposed synthesis approach is validated with the design of a tri-band power amplifier at frequency bands 0.90, 1.85 and 2.40 GHz. For a continuous-wave measurement, the peak drain efficiency is 70.0%, 67.1% and 59.8% at 0.90, 1.85 and 2.40 GHz, respectively.