Design and implementation of low-phase-noise temperature-compensated crystal oscillator

Phase noise within the half-bandwidth of the loop is closely related to the loaded quality factor Q_L. The importance of loaded quality factor Q_L and the method to reduce phase noise on the basis of improving QL are introduced in this paper. STM32F103RCT6 MCU and AT-cut third-overtone 100-MHz quartz crystal resonator are used to achieve a 100-MHz low-phase-noise temperature compensated crystal oscillator prototype. After temperature compensation and reducing phase noise, the measured temperature performance of the 100-MHz low-phase-noise MTCXO are better than ±0.45 ppm/-30 °C-+50 °C, and measured phase noise results are better than -157 dBc/Hz at 1 kHz and -170 dBc/Hz at 10 kHz.