A Cryogenic Low Phase Noise MEMS Oscillator Based on 433 MHz SAW Resonator

Micro-Electro-Mechanical Systems (MEMS) Surface Acoustic Wave (SAW) devices excel in Radio Frequency (RF) technology due to their advanced features, miniaturization, and high performance. In this paper, we investigate the performance of a 433 MHz MEMS oscillator operating at 4K. The oscillator integrates a commercial SAW resonator, an E-PHEMT low noise amplifier (LNA), and a π-type phase shifter. We measured the characteristics of both the open-loop and closed-loop circuits. The results demonstrated that at 4K, the phase noise at 100 kHz offset frequency is −83.60 dBc/Hz. Furthermore, the oscillation frequency at 4K is observed to be 0.8 MHz lower than at 300K.