核磁共振陀螺原子核自旋进动的建模与仿真  

Modeling and Simulation of Nuclear Spin Precession in Nuclear Magnetic Resonance Gyroscope

作　　者：陈晓格 舒强 朱明智[1] 汪宝旭[1] CHEN Xiao-ge;SHU Qiang;ZHU Ming-zhi;WANG Bao-xu(Institute of Systems Engineering,CAEP,Mianyang 621999)

机构地区：[1]中国工程物理研究院总体工程研究所,绵阳621999

出　　处：《导航与控制》2018年第6期94-101,60,共9页Navigation and Control

摘　　要：针对^(87)Rb-^(129)Xe核磁共振陀螺中原子核的自旋进动,基于核磁共振Bloch方程,给出了Xe原子核自旋进动模型,详细分析了横向激励磁场的相位和幅值对Xe原子宏观磁矩进动的影响,以及实现稳态进动的条件。建立了Xe原子宏观磁矩进动的仿真模型,对激励磁场反馈控制、陀螺角位移信号相位解调进行了仿真。分析和仿真结果表明,当载体系旋转时,陀螺角位移线性调制Xe原子宏观磁矩水平分量的进动相位,为了维持磁共振,横向激励磁场相位应与宏观磁矩y向分量的进动相位保持一致;模型能够准确地实现对陀螺载体坐标系旋转位移的观测。For nuclear spin precession in the 87Rb-129Xe nuclear magnetic resonance gyroscope (NMRG), a model of the nuclear spin precession of Xenon isotope is presented based on Bloch equations. The influences of the phase and amplitude of transverse driving magnetic field on the macroscopic magnetic moment precession of Xenon isotope are analyzed. The conditions when the steady precession occurs are given. The simulation model of the macroscopic magnetic moment precession of Xenon isotope, magnetic field feedback control, and a signal phase demodulator module are established and simulated. The analysis and simulation show that the phase of the macroscopic magnetic moment precession in xy-plane is modulated linearly by the angular displacement of the gyroscope. When the gyroscope frame rotates, the phase of the transverse driving magnetic field should closely follow the y-component phase of the macroscopic magnetic moment. The model can accurately estimate the rotation displacement of the gyroscope frame.

关 键 词：核磁共振陀螺 核自旋进动 BLOCH方程 反馈控制 相位解调 建模 仿真 

分 类 号：V241.557[航空宇航科学与技术—飞行器设计]