Study on Harmonic Spur Characteristics of AlGaN/GaN HEMT PA at Different Temperatures

The harmonic spur characteristics of AlGaN/GaN power amplifiers (PA) at different temperatures are studied in this paper. Load-pull method is at first applied for the design of a C-band PA, which offers a peak output power of 48dBm (80W) with drain efficiency (DE) higher than 30%, and adjacent channel power ratio (ACPR) performance is less than -38 dBc. A temperature test chamber is used to provide desired temperature environment for measuring both power output and ACPR performance of the PA sample form low to high temperatures. Further, harmonic spur characteristics of the designed PA are measured, and it is shown that the harmonic spur power of PA increases with temperature in an approximately linear way.