2025 Volume 22 Issue 2 Pages 20240659
This letter proposes a novel design method for a resistive-resistive series of continuous modes (Res-Res SCMs) power amplifier (PA), which can extend the bandwidth of the SCMs PAs. With a waveform engineering method, we introduce the resistive part to the purely reactive second harmonic load of SCMs to overcome one-octave bandwidth limitation of traditional continuous PAs. The limitation is due to the inability to overlap between low-band and high-order harmonics and high-band fundamental waves. An ultra-wideband PA module across 0.4-3.1 GHz (154.3% bandwidth) is fabricated using a 10 W GaN HEMT device. The experimental results show a drain efficiency of 63%-81.7% can be achieved with a saturated output power of 38.6-42.3 dBm at 0.4-3.1 GHz.