In view of the poor scale factor stability of the interferometric fiber optic gyroscope(IFOG),it is a creative method to use laser to drive the IFOG for its better frequency stabilization characteristics instead of th...In view of the poor scale factor stability of the interferometric fiber optic gyroscope(IFOG),it is a creative method to use laser to drive the IFOG for its better frequency stabilization characteristics instead of the broadband light source.As the linewidth of laser is narrow,the errors of coherent backscattering,polarization coupling,and Kerr effect are reintroduced which cause more noise and drift.This paper studies laser spectrum broadening based on external phase modulation of Gaussian white noise(GWN).The theoretical analysis and test results indicate that this method has a good effect on spectrum broadening and can be used to improve the performance of the laser-driven IFOG.In the established closed-loop IFOG,a four-state modulation(FSM)is adopted to avoid temperature instability of the multifunction integrated-optic chip(MIOC)and drift caused by the electronic circuit in demodulation.The experimental results show that the IFOG driven by broadened laser has the angular random walk noise of 0.0038°/√h and the drift of 0.017°/h,which are 62%and 66%better than those without modulation respectively,of which the drift has reached the level of the broadband light source.Although the noise still needs further reduction,its scale factor stability is 0.38 ppm,which has an overwhelming advantage compared with the traditional IFOG.展开更多
在干涉式光纤陀螺组成的捷联惯性导航系统中,光纤陀螺启动过程中温变效应导致的漂移项是导航误差的主要误差源,已成为限制高精度光纤陀螺系统性能进一步提升的关键因素。通过对光纤陀螺启动过程中温变效应的理论分析与建模,提出了一种...在干涉式光纤陀螺组成的捷联惯性导航系统中,光纤陀螺启动过程中温变效应导致的漂移项是导航误差的主要误差源,已成为限制高精度光纤陀螺系统性能进一步提升的关键因素。通过对光纤陀螺启动过程中温变效应的理论分析与建模,提出了一种基于查表补偿的光纤陀螺启动温变效应误差抑制法和误差评价法。实验结果表明,该抑制方法可使-40^+60℃环境下光纤陀螺漂移概率误差从0.02~0.50(°)/h降至0.01(°)/h以下,对应导航系统的导航圆概率误差从1.4~35 n mile/h降至0.8 n mile/h以下,有效抑制了光纤陀螺启动温变效应误差,提升了系统性能。展开更多
文摘In view of the poor scale factor stability of the interferometric fiber optic gyroscope(IFOG),it is a creative method to use laser to drive the IFOG for its better frequency stabilization characteristics instead of the broadband light source.As the linewidth of laser is narrow,the errors of coherent backscattering,polarization coupling,and Kerr effect are reintroduced which cause more noise and drift.This paper studies laser spectrum broadening based on external phase modulation of Gaussian white noise(GWN).The theoretical analysis and test results indicate that this method has a good effect on spectrum broadening and can be used to improve the performance of the laser-driven IFOG.In the established closed-loop IFOG,a four-state modulation(FSM)is adopted to avoid temperature instability of the multifunction integrated-optic chip(MIOC)and drift caused by the electronic circuit in demodulation.The experimental results show that the IFOG driven by broadened laser has the angular random walk noise of 0.0038°/√h and the drift of 0.017°/h,which are 62%and 66%better than those without modulation respectively,of which the drift has reached the level of the broadband light source.Although the noise still needs further reduction,its scale factor stability is 0.38 ppm,which has an overwhelming advantage compared with the traditional IFOG.
文摘在干涉式光纤陀螺组成的捷联惯性导航系统中,光纤陀螺启动过程中温变效应导致的漂移项是导航误差的主要误差源,已成为限制高精度光纤陀螺系统性能进一步提升的关键因素。通过对光纤陀螺启动过程中温变效应的理论分析与建模,提出了一种基于查表补偿的光纤陀螺启动温变效应误差抑制法和误差评价法。实验结果表明,该抑制方法可使-40^+60℃环境下光纤陀螺漂移概率误差从0.02~0.50(°)/h降至0.01(°)/h以下,对应导航系统的导航圆概率误差从1.4~35 n mile/h降至0.8 n mile/h以下,有效抑制了光纤陀螺启动温变效应误差,提升了系统性能。