一种宽频率调节的精密OCXO

在精密标准频率控制仪器中，常常需要既能在宽频率范围调节又能够保持高频率稳定度和低相位噪声的可控晶体振荡器．为了实现宽频率范围调节，不得不采用拉动性好但是稳定度和老化率较差的基频晶体振荡器．虽然基于SC切泛音晶体的高精度恒温控制晶体振荡器(OCXO)显现出非常高的频率稳定度和低老化率，但是它的电压控制频率调节范围很窄，无法在锁相受控的情况下使用．针对更宽的频率调节范围，笔者提出一种新的方法，即通过对温度控制来调节OCXO的频率．所有精密OCXO的良好性能都可以保持下来，同时，原来的10^-7量级电压可控频率范围提高到5×10^-6量级或者更宽．这样就能够在需要长期稳定锁定的频率源，如星载的原子钟中得到应用，保证了系统稳定优良的指标．

Wide frequency-regulated Precision OCXO

When precision standard frequency control devices are used, we always need controllable crystal oscillators that not only can be regulated in a wide frequency range, but also can maintain high frequency stability and low phase noise. In order to realize the wide frequency range, we have to use the crystal oscillator which shows good pull ups, but at the same time poor frequency stabilities and aging. High precision Oven-Controlled Crystal Oscillator(OCXO) based on SC cut overtone crystals can show very high frequency stability and low aging. However, its frequency regulation range by voltage control is not wide. When it is phase locked and controllable, it can not be used. In connection with a wider frequency regulation range, a new method is proposed through the regulation of the control temperature of the OCXO. In this way, all the good performances of the precision OCXO can be kept, and the original 10^-7 order voltage-controllable frequency range is improved to 5×10^-6 or even wider at the same time. Then it can be used in the frequency source which needs to be stably locked for a long time such as an on-board atomic clock,to ensure the stable and excellent indexes of the system.