基于FPGA的星载被动型氢钟数字温控技术研究

Research on digital temperature control technology of space passive hydrogen maser based on FPGA

原子钟作为一种量子时间计量仪器,温度变化对其长期性能有较大影响。微波谐振腔是被动型氢原子钟的核心,分析了温度变化对谐振腔物理特性的影响,为使被动型氢钟频率稳定度达到10^(-15)/d量级的要求,微波谐振腔部分的温度变化不能超过0.02℃/d。本文设计了一种低噪声的精密温度控制系统,并对被动型氢原子钟进行温度控制。实验结果显示,当外界环境温度变化不超过1℃时,44 h内谐振腔腔中温度波动小于0.005℃,性能优异。该方案为被动型氢原子钟数字电路的后续改进提供了依据,可应用于小型化星载氢钟设计。

As a quantum time measuring instrument,the temperature change of atomic clock has a great impact on its long-term performance.Microwave cavity is the core of the passive hydrogen maser.This paper analyzes the influence of temperature change on the physical characteristics of the cavity.In order to make the frequency stability reach the level of 10^(-15)/d,the temperature change of the microwave cavity should be no more than 0.02℃/d.In this paper,a low-noise precision temperature control system is designed to control the temperature of the passive hydrogen maser.The experimental results show that when the external temperature does not change more than 1℃,the temperature fluctuation of the cavity is less than 0.005℃within 44 hours,and the performance is excellent.This scheme provides a basis for the subsequent optimization of digital circuit of the passive hydrogen maser and can be applied to the design of a miniaturized space hydrogen maser.