变温环境下谐振式光纤陀螺偏振误差研究  

Study on Polarization Error of Resonant Fiber Optical Gyroscopes in Varying Temperature Environments

作　　者：高天香 李俊[2] 蓝士祺 吴凡[2] 程峻 齐新元 Gao Tianxiang;Li Jun;Lan Shiqi;Wu Fan;Cheng Jun;Qi Xinyuan(School of Physics,Northwest University,Xi'an 710127,Shaanxi,China;National Key Laboratory of Science and Technology on Aircraft Control,Flight Automatic Control Research Institute,Xi'an 710076,Shaanxi,China)

机构地区：[1]西北大学物理学院,陕西西安710127 [2]西安飞行自动控制研究所飞行器控制一体化技术国防科技重点实验室,陕西西安710076

出　　处：《光学学报》2023年第19期106-114,共9页Acta Optica Sinica

摘　　要：偏振噪声是谐振式光纤陀螺谐振腔中较为严重的光学噪声之一。基于琼斯矩阵的方法建立完整的光路传输模型,对谐振腔顺时针和逆时针两路光传输进行分析,得到环境温度在-40℃~80℃范围内变化时偏振噪声导致的陀螺误差。结果表明,在线起偏器消光比为30 dB时,耦合器直通端对准角度误差小于2.78°,耦合系数为0.05,双90°熔接点两侧光纤长度差容错值在0.207 m以内,使得陀螺输出误差小于0.01(°)/h。基于此,当陀螺系统工作导致内部温度分布非均匀时,谐振腔上每相邻两段光纤间温度分布差需小于3.122℃。各影响因素的参数选择可为变温环境下由于偏振噪声导致的误差分配设计提供理论指导。Objective In response to the need for high-precision and engineering applications of resonant fiber optical gyroscopes(RFOGs),research is conducted on the relevant factors that affect polarization noises and thus the output error of gyroscopes in varying temperature environments.Polarization noise is one of the main optical noises that cause output errors in RFOGs.Since the core sensitive component of RFOGs,namely the fiber ring resonator(FRR),is mostly wound by polarization maintaining optical fiber,when the birefringence index of polarization maintaining optical fibers changes with temperature,it will cause the superposition and interference effects of the resonant light waves corresponding to the two intrinsic polarization states of the resonator,resulting in asymmetry in the resonance curve,polarization noises,and detection errors at the resonance frequency point and thereby causing gyro output errors.Therefore,suppressing polarization noise in varying temperature environments has profound significance.The measures taken by researchers to suppress polarization noise can be divided into two categories:stabilizing the phase difference between primary and secondary polarization and reducing the intensity of secondary polarization states.Researchers have successively adopted a single 90°fusion joint scheme within the FRR,a twin 90°fusion polarization maintaining transmission FRR scheme,and a secondary polarization axis rotation fusion polarization starting resonant cavity to stabilize the primary and secondary polarization phase difference.Researchers have reduced the intensity of secondary polarization states by inserting polarization controllers,online polarizers,etc.into the FRR or utilized a new fiber optic scheme to reduce the impact of polarization noises on the gyroscope.The above studies have achieved good results in noise suppression,but most studies have been conducted at room temperature or small-range temperature variations.When facing engineering applications,gyroscopes need to improve their enviro

关 键 词：谐振式光纤陀螺 琼斯矩阵 偏振噪声 变温环境 

分 类 号：V241.59[航空宇航科学与技术—飞行器设计]