فهرست نشریات علمی دسترسی آزاد ایران

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.