A 30-to-60-GHz Monolithic HEMT Frequency Doubler

Using 0.3-¿m AlGaAs/GaAs HEMT technology, we developed a 30-to-60-GHz monolithic frequency doubler which has a conversion loss of 5 dB and a fundamental signal suppression of 20 dB for a 0-dBm 30-GHz input signal. The doubler´s performance is superior to those using similarly scaled AlGaAs/GaAs HEMT. For the design, we used a nonlinear circuit simulator based on the harmonic balance method, an empirical nonlinear HEMT model, and an electromagnetic field simulator. The calculated and measured results agreed well. We developed this in order to build a 60-GHz AlGaAs/GaAs HEMT-based single-chip monolithic transceiver.