四频差动激光陀螺工作点的选择

当四频差动激光陀螺工作于增益曲线上左、右旋陀螺比例因子相等位置时,误差因素在拍频的差动中得到较好的抵消,因而具有较优的性能。为了从实验上寻找该最佳工作点,对四频差动激光陀螺拍频表达式进行了分析,发现静态下和频的电压扫描曲线呈抛物线变化,而且当左、右旋陀螺比例因子相等时,和频的电压扫描曲线处于转折点。设计了实验通过和频电压扫描曲线得到了理论最佳工作点,在不同工作点下对陀螺进行测试,根据其零偏稳定性随工作点的变化趋势,得到了实测最佳工作点。对某型5个陀螺的多次实验表明,由和频电压扫描曲线得到的理论最佳工作点与实测最佳工作点基本一致,最大误差2Hz。该方法可作为四频陀螺选择最佳工作点的参考方法。

Choice of Operating Point for the Four-Mode Differential Laser Gyros

The four-mode differential laser gyros(FMDLGs)would have better performance when operating at the point with equal scale factors for left circularly polarized(LCP)and right circularly polarized(RCP)gyros.In order to find the optimal operating point,expressions for FMDLG beat frequency are analyzed.Theoretical study shows that the sum frequency as a function of piezoelectric transducer(PZT)scanning voltage is quadratic and the scale factors of the LCP and RCP gyros are equal when the quadratic function is at its turning point.Therefore,theoretical optimal operating point can be obtained by recording beat frequency of the FMDLG while scanning the PZT voltage.And actual optimal operating point can be obtained by testing the FMDLG at different operating point.Experimental results give an approximate coincidence of theoretical and actual optimal operating point with maximum error of 2 Hz,which shows a reference method to choose optimal operating point for FMDLGs.