Simulation program and application analysis of nuclear magnetic resonance gyroscope signal considering Rb-Xe coupling

The nuclear magnetic resonance gyroscope (NMRG) holds significant promise for applications in unmanned systems, smart devices, and deep-sea/space exploration. However, its advancement is constrained by multiphysical interference and coupling effects. Current techniques lack the capability for high-precision multi-axis decoupling or accurate mechanistic analysis of performance-limiting factors, restricting further enhancements in accuracy. To overcome this, we developed a signal simulation program incorporating critical NMRG physical effects, Rb-Xe coupling, carrier demodulation, and phase-locked loop (PLL) feedback control, using a fourth-order Runge-Kutta numerical solver. The model was validated through dual verification via main magnetic field variations and closed-loop PLL phase shifts, achieving an error margin below 0.2%. Using this platform, we systematically evaluated the impact of magnetic field parameters on key performance metrics: signal amplitude, resonance frequency, signal-to-noise ratio (SNR), and 100-second standard deviation. Key findings include: (i) Signal intensity and SNR display distinct trends under varying field parameters, likely due to field-dependent noise modulation; (ii) PLL excitation amplitude and phase exert the strongest influence on the 100-second deviation (\sim 0.015^\circ/h), followed by high-frequency carrier excitation amplitude, with other parameters contributing under 0.005^\circ/h; (iii) Optimizing the 100-second deviation requires leveraging the synergy between signal intensity and SNR. This simulation tool offers dual utility: guiding quantitative parameter optimization and system debugging in practical applications of NMRG, and visualizing the evolution of Rb and Xe atomic moments under varying fields, thereby improving mechanistic insight into NMRG operation.