Low-Power and Low-Phase Noise 94-GHz and 107.2-GHz Differential Fundamental Oscillators in 70-nm GaAs pHEMT Technology

This paper presents a family of four W-band (75–110 GHz) differential fundamental oscillators (94/102.7/104.4/107.2 GHz) implemented in a state-of-the-art 70-nm GaAs pHEMT (PP07) technology, featuring a peak fT/fmax of 160/360 GHz. The differential oscillator core utilizes cross-coupled transistor pair with an inherently grounded source which is optimized for mm-wave performance. The 94-GHz oscillator delivers a phase noise and a differential output power of -115.2 dBc/Hz (10-MHz offset) and -3 dBm, respectively, while consuming 74.5 mW. The 107.2-GHz oscillator, with a reduced mesa for enhanced performance, achieves a phase noise of -113.3 dBc/Hz (10-MHz offset) and a differential output power of -8.8 dBm while consuming only 29 mW, including the output buffers. To the best of the authors’ knowledge, these mm-wave oscillators achieve the highest oscillation frequency with low phase noise and low DC power consumption among prior published GaAs pHEMT single-ended and differential fundamental oscillators reported to date.