Comparative Noise Analysis of Readout Circuit in Hemispherical Resonator Gyroscope

Area of Science:

• Instrumentation and Measurement
• Electronics Engineering
• Physics

Background:

• Readout circuit noise is a critical factor limiting precision in Hemispherical Resonator Gyroscope (HRG) control systems.
• Understanding noise sources in amplifiers like the Transimpedance Amplifier (TIA) and Charge-Sensitive Amplifier (CSA) is essential for improving resonator displacement detection.

Purpose of the Study:

• To compare the noise characteristics and contribution mechanisms of TIA and CSA in HRG readout circuits.
• To identify the dominant noise sources and evaluate their impact on detection precision.
• To provide guidance for selecting and designing HRG readout circuits.

Main Methods:

• Development of a comprehensive noise model for TIA and CSA.
• Analysis of circuit bandwidth and feedback network effects.
• Simulation and experimental validation of theoretical noise models.

Main Results:

• Feedback resistor thermal noise dominates TIA noise (99.8%).
• CSA exhibits significantly lower output noise (13.2 μVrms) compared to TIA (25.8 μVrms), a 48.8% reduction.
• CSA achieves superior equivalent displacement noise (1.69×10-14m/Hz) versus TIA (1.27×10-13m/Hz), an 86.7% improvement.

Conclusions:

• The CSA's capacitive feedback network effectively suppresses high-frequency noise, making it more suitable for high-precision HRG applications.
• The study validates theoretical noise models with experimental data.
• Findings offer valuable theoretical and technical references for HRG readout circuit design.