high-efficiency l-band gan power amplifier employing second and third harmonic impedance optimization

This paper presents the design and evaluation of a high-efficiency harmonic tuned l-band power amplifier (pa) utilizing a gallium nitride (gan) high electron mobility transistor (hemt). to meet the demands of modern wireless communication and radar systems operating in the l-band, advanced harmonic tuning techniques were employed, specifically focusing on controlling the impedance terminations at the second (2f₀) and third (3f₀) harmonic frequencies. through careful load-pull analysis and optimized output matching network design, precise harmonic terminations were achieved alongside optimal fundamental frequency impedance matching. the fabricated pa demonstrates state-of-the-art performance, delivering a saturated output power (psat) of 46.4 dbm with a corresponding peak power added efficiency (pae) of 83%. critically, the pa maintains high efficiency under back-off conditions, achieving 60% pae at 3 db output back-off (obo). these results highlight the effectiveness of this combined second and third harmonic optimization approach with gan hemt technology, which enables both high peak efficiency and excellent back-off efficiency for demanding l-band applications.