28 GHz MMIC resonant tunnelling diode oscillator of around 1mW output power

Presented is a monolithic microwave integrated circuit (MMIC) resonant tunnelling diode (RTD) oscillator that employs two In_0.53Ga_0.47As/AlAs RTDs (5 × 5 μm²) in parallel. The oscillator works at 28.7 GHz with -0.7 dBm output power. The phase noise was -95 dBc/Hz at 100 kHz and -114 dBc/Hz at 1 MHz offset. This reported work demonstrates the potential of RTD oscillators in achieving high output power at high frequencies by utilising suitable power maximising and combining techniques.