激光陀螺抖动偏频优化研究

Study on Optimization of Dither Bias for Ring Laser Gyroscope

基于频率调制理论,分析、仿真计算了正弦抖动偏频和优化后的正弦抖动偏频条件下,激光陀螺输入-输出曲线的特点.结果表明:正弦抖动偏频时激光陀螺的输入-输出曲线在抖动频率的倍频点处存在着动态锁区,其宽度与激光陀螺静态锁区、抖动角振幅有关.采用优化后的正弦抖动偏频可以很好地克服动态锁区,大大提高激光陀螺输入-输出曲线的线性度.试验对比了正弦抖动偏频和优化后的正弦抖动偏频条件下激光陀螺的输出性能.试验结果表明:采用优化后的正弦抖动偏频显著提高了陀螺准确度.

The input-output curve characteristic of ring laser gyroscope with dither bias and optimized dither bias is analyzed and simulated. The results of analysis and simulation show that the existence of dynamic lock-in is centered around the harmonics of the dither frequency when dither bias is used. The width of this dynamic lock-in is related to natural lock in of ring laser gyroscope and magnitude of the dither amplitude. The dynamic lock-in can be well overcome when dither bias is optimized. Thus the linearity of the input- output curve of ring laser gyro is improved greatly. The performance of ring laser gyroscope with dither bias and optimized dither bias is tested and compared. The results show that the performance of ring laser gyroscope is improved greatly when using optimized dither bias.