基于数字滤波的激光陀螺数字信号处理算法

Digital signal processing algorithm of laser gyro based on digital filter

基于Sagnac效应的激光陀螺,信号输出为天然的数字形式,高速数字信号处理器为数字滤波提供了硬件平台,在现有研制精度和工艺水平下,激光陀螺输出信号的滤波算法好坏直接影响其精度。采集激光陀螺0.25 ms原始测试数据,并以此为研究对象,首先采用改进的FIR、IIR滤波算法进行了处理,然后从算法的实时性、处理精度等方面讨论了改进算法的优缺点,最后为激光陀螺选定了最优的滤波算法:IIR滤波+13阶FIR滤波。试验表明,相对于34阶FIR滤波,选定的滤波算法在不减低系统精度的基础上,将系统的时延从传统的3.625 ms降至1.805 ms左右,极大提高了制导系统的实时性,具有重要的工程参考价值。

The working of laser gyro is based on Sagnac effect,and its output signals are digital form naturally.High speed digital signal processor provides a hardware platform for digital filter.Under the existing researches and technological level,the quality of filter algorithm of laser gyro output signal directly influences its precision.In this paper,0.25 ms raw test data were sampled and used as research object,and the improved FIR and IIR filter algorithms were used to deal with them.The advantages and disadvantages of the improved algorithm were discussed from its real-time characteristic and processing accuracy.Finally,an optimal filter algorithm was selected for laser gyro：IIR filter ＋13 orders filter.The test results show that,in comparison with 34 orders FIR filter,the selected filter algorithm can reduce system＇s time delay from traditional 3.625 ms to about 1.805 ms without reducing its precision.Thus the guidance system＇s real time is significantly improved,and this has important reference value in engineering application.