A microwave comb generator based on AlGaN/GaN heterostructure Schottky diodes nonlinear transmission line

We report a microwave nonlinear transmission line (NLTL) based on AlGaN/GaN Schottky-barrier diodes. As a comb generator, the NLTL produces a frequency comb from 4 to 40 GHz at an input frequency of 4 GHz. The power of harmonics from 28 to 40 GHz exceeds that of commercial GaAs NLTL at an input power of 26 dBm. The power of harmonic starts to saturate as the input power increases to 33 dBm. Compared with the maximum input power of 26 dBm of commercial GaAs NLTLs, the comb generator based on AlGaN/GaN NLTL is more advantageous at a high input power.