一种高稳定正弦载波产生电路的设计与研究

Design and research of a high stable sinusoidal carrier generation circuit

高稳定正弦载波产生技术是电容位移传感任务中的关键技术,能否精确实现高精度电容位移传感直接关系到空间引力波探测核心载荷的指标实现。在空间引力波探测任务中,对惯性传感器关键技术--高精度电容位移传感技术中的高稳定正弦载波产生电路进行研究,通过将直接数字频率合成(direct digital system,DDS)中影响正弦载波幅值稳定度的因素进行改良,确定了采用基于DDS技术改良的阶梯波滤波法作为正弦载波产生方法,通过模型建立、理论分析对电路展开研究,在不考虑温度影响的前提下,常温下正弦载波的幅值稳定度指标可达到21 ppm/Hz。

The high stable sinusoidal carrier generation technology is the important technology in capacitive displacement sensing task.Whether the capacitive displacement sensing can be realized accurately is directly related to the realization of the core load index of space gravitational wave detection.In the space missions of the gravitational waves,the high stable sinusoidal carrier generation technology based on the important technology of the inertial sensor-high-precision capacitance displacement sensing technology is researched.By improving the factors affecting the waveform stability in direct digital system(DDS),the improved step wave filtering method based on DDS technology is determined as the sinusoidal wave generation method.Through model building and theoretical analysis,the circuit is studied and the sinusoidal wave stability index at normal temperature can reach 21 ppm/Hz without considering the influence of temperature.