A power detector based on GaN high-electron-mobility transistors for a gigabit on–off keying demodulator at 90 GHz

This study analyzes the mechanism behind signal demodulation in GaN high-electron-mobility transistors, finding the relationship between gate bias voltage and relative amplitude of the output voltage. The optimal gate bias for maximum responsivity has been analytically found. The responsivity of the GaN demodulator at different biases has been characterized using an on–off keying signal with a 90 GHz carrier. Furthermore, from the measured eye diagram it is observed that the GaN demodulator can demodulate a signal with a maximum data rate up to a 1.28 gigabits per second. This study presents a promising method for integrating a GaN demodulator into a single-chip GaN transceiver.