Design of a 0.4-3.9-GHz Wideband High-Efficiency Power Amplifier Based on a Novel Bandwidth Extended Matching Network

The design of a multi-octave power amplifier (PA) is presented based on extended continuous Class-B/J (ECB/J) modes in this paper. The wide design space provided by the ECB/J modes has been used as the goal for the design. A unique bandwidth extended matching network that can achieve a broadband impedance matching in the appropriate impedance region by simultaneously manipulating six frequency points is proposed to compensate for the impedance dispersion effect caused by the change of the optimal impedance with the operating frequency in the design of the matching network. To verify the proposed methodology, a wideband PA is designed and fabricated by using a commercial 10-W gallium nitride (GaN) device. The implemented PA achieves a bandwidth of 163% from 0.4 to 3.9 GHz while exhibiting excellent performance of 38-42.3 dBm output power, 57-68% drain efficiency, and 10-13 dB gain. The measured adjacent channel power ratio (ACPR) is lower than -26 dBc at 0.8, 1.5, 2.0, 2.5, 3.0, and 3.5 GHz when the output power is lower than 36 dBm.