解调电路相位自动对齐系统设计与实现  

Design and implementation of phase automatic alignment system for demodulation circuit

作　　者：薛科 于涛[1] 汪龙祺[1] 隋延林[1] 陈泳锟 陈禹竺 刘鑫[1] XUE Ke;YU Tao;WANG Longqi;SUI Yanlin;CHEN Yongkun;CHEN Yuzhu;LIU Xin(Changchun Institute of Optics,Fine Mechanics and Physics,Chinese Academy of Sciences,Changchun 130033,China)

机构地区：[1]中国科学院长春光学精密机械与物理研究所,吉林长春130033

出　　处：《现代电子技术》2023年第9期163-167,共5页Modern Electronics Technique

基　　金：国家重点研发计划课题(2020YFC2200604)。

摘　　要：在空间引力波探测项目中,能否实现高精度电容位移传感技术直接关系到项目的核心指标实现。在电容位移传感链路中,解调电路去除噪声能力限制整条链路性能,其中,参考信号与输入信号之间的相位差影响电路去除噪声能力。为了最大限度地提高系统的信噪比,针对当前研究的局限性,提出一种解调电路相位自动对齐系统。首先,介绍了整个系统的构成;其次,对基于动量下降法的相位对齐方法进行详细介绍,参考信号相位自动移动,移动的步长根据动量梯度下降法动态调整;然后,提出对相敏检测器的波形进行检测;接着结合两个方法提出解调电路相位自动对齐系统,提高了系统的可靠性和抗干扰性;最后用标定平台模拟电容位移传感中的电容差,将文中提出的方法与遍历相位对齐法进行比较,发现该方法能够准确地对齐相位,性能平均提升0.136%,同时在示波器上观察信号相位已经准确对齐。In the space gravitational wave detection project,the realization of high⁃precision capacitive displacement sensing technology is directly related to the realization of the core indicators of the project.In the space gravitational wave detection project,the realization of high precision capacitive displacement sensing technology is directly related to the realization of the core indicators of the project.In capacitive displacement sensing link,the demodulation circuit′s noise removal ability limits the performance of the whole link,where the phase difference between the reference signal and the input signal affects the circuit′s noise removal ability.Aiming at the limitation of current research,in order to maximize the SNR of the system,a demodulation circuit phase automatic alignment system is proposed.Firstly,the constitution of the whole system is introduced.The phase alignment method based on momentum descent method is introduced in detail.The phase of the reference signal moves automatically,and the moving step is adjusted dynamically according to the momentum gradient descent method.Then,the waveform of phase sensitive detector is detected.Then the phase automatic alignment system of demodulation circuit is proposed by combining the two methods,which improves the reliability and anti⁃interference of the system.The calibration platform is used to simulate the capacitance difference in capacitance displacement sensing.The proposed method is compared with the ergodic phase alignment method.It is found that the proposed method can accurately align the phase with an average performance improvement of 0.136%.

关 键 词：引力波探测 电容位移传感 微弱信号 解调电路 相敏检波 动量梯度下降法 波形检测 系统设计 

分 类 号：TN710-34[电子电信—电路与系统] TP29[自动化与计算机技术—检测技术与自动化装置]