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本文首先通过正弦波调制下干涉信号光强分析解调出光纤陀螺的输出信号,进而得出残余强度调制存在的情况下陀螺输出信号的变化情况,同时,通过分析陀螺信号的变化说明残余强度调制对光纤陀螺性能的影响与陀螺精度要求有关,精度越高,其影响越明显.其次,具体分析了数字闭环光纤陀螺受残余强度调制影响的情况下,其解调输出电压变化引起的数字阶梯高度变化,并通过残余强度调制系数与数字阶梯高度的关系式,说明了残余强度调制对光纤陀螺零偏和标度因数的影响.最后,对所得出的残余强度调制系数与光纤陀螺标度因数稳定性的关系进行了Matlab仿真,通过仿真结果,更进一步说明残余强度调制对数字闭环光纤陀螺标度因数稳定性的影响. 相似文献
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高精度光纤陀螺信号的在线建模与滤波 总被引:2,自引:1,他引:2
针对高精度光纤陀螺随机误差,在分析其一般时间序列模型的基础上,提出了一种改进型二阶自回归AR(2)模型,可以在线建立光纤陀螺随机误差模型.根据该模型,采用卡尔曼滤波算法,实现了光纤陀螺惯导系统在对准与导航过程中光纤陀螺随机误差的实时滤波.滤波结果和Allan方差分析证明,光纤陀螺信号中角随机游走、零偏不稳定性、速率随机游走、速率斜坡和量化噪声五项噪声源误差系数都小于滤波前的二分之一,有效减小了光纤陀螺随机误差,提高了光纤陀螺精度. 相似文献
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利用开环正弦波调制解调方法,推导了铌酸锂相位调制器的残余强度调制(简称RIM)对干涉型光纤陀螺(简称IFOG)信号的影响,指出在调制频率漂移或光纤环渡越时间变化时RIM可导致陀螺的零偏和噪声增大.对典型条件的计算表明,0.01°/h的IFOG容许的最大RIM为13ppm,0.1°/h的中低精度IFOG则为81ppm.提出利用锁相放大器精确测量相位调制器RIM的方法,并对国产器件进行测量,结果表明,器件RIM指标可在中低精度IFOG中应用. 相似文献
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光纤型偏振OCT 系统中光偏振特性的研究 总被引:2,自引:0,他引:2
建立了偏振光在生物组织中传播的模型,并利用该模型模拟了偏振光在生物组织中传播的过程,重建了多种偏振态输入光的情况下光偏振态在生物组织中的分布及生物组织的偏振特性模型.分析了光偏振度与光被生物组织散射次数的关系,阐明了由于偏振光在组织中传播,其偏振态逐渐改变而造成的偏振OCT 干涉计两臂光束失去相干性及偏振OCT 图像质量下降现象.通过分析斯托克斯(Stokes)矢量和穆勒(Muller)矩阵在光纤型偏振OCT系统中的应用,说明Muller 矩阵不受输入光偏振态的影响,因此它比Stokes 矢量更适用于光纤型偏振OCT 系统研究. 相似文献
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Amol V. Pansare Shyam R. Khairkar Amol A. Shedge Shraddha Y. Chhatre Vishwanath R. Patil Amit A. Nagarkar 《Advanced materials (Deerfield Beach, Fla.)》2018,30(33)
In situ reduction of chloroauric acid inside an amine‐cured epoxy matrix leads to formation of gold nanoparticles which are embedded inside the part. This phenomenon is leveraged to design an authentication system for composites wherein the particles are embedded spatially and are invisible to the naked eye. Under UV light, the particles diffract light and create an easily visible path. The particles penetrate inside the part and create a permanent, cost‐effective, tamper‐proof code. The advantage of this technique is that this authentication system can be built in composite parts after fabrication of the composite structure. As very small amount (nanograms) of particles are present in the part, negligible change in the thermal characteristics of the parent matrix is observed. The particles can be embedded easily in carbon fiber as well as glass fiber reinforced epoxy structures. 相似文献
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保证陀螺经纬仪寻北精度的同时,缩短寻北时间实现快速寻北具有重要意义.从陀螺仪寻北原理出发,建立陀螺运动轨迹的数学模型.基于数字化测量光路建立了非线性回归模型,通过欠周期的采集数据,预测整周期函数信息,研究1/8周期快速寻北方法,实现陀螺开始寻北1 min以内高精度快速寻北,开辟快速寻北的新途径.以改进型JT-15陀螺仪为样机的寻北试验表明,在陀螺开始寻北56 s内,仪器寻北测量精度优于0.831 1’. 相似文献
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光纤陀螺性能数字评价系统的可视化研究 总被引:2,自引:0,他引:2
开发了一种接收并处理光纤陀螺信号的数字评价系统,它通过计算光纤陀螺的零漂、零偏重复性、标度因数等来评价光纤陀螺的性能。在Windows平台下采用VC 设计的数字采集处理系统能够实时控制进程、高速收发数据以及用图形和文字可视化显示其结果,并引进了帧结构来减少传输误差,使系统的可靠性增加,误码率也同时降低。 相似文献
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反射式光纤测振仪的研究 总被引:3,自引:0,他引:3
提出了一种反射式光纤测振系统。为克服环境、温度、光源输出、光路损耗等变化引起的漂移,它采用与反射面距离不等的两根接受光纤为参考通道,并利用两根接受光纤输出的信号比构成自补偿网络。本文给出该网络的理论依据,并介绍如何在电路设计上采用相应措施来提高稳定性和保证测试精度 相似文献
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É. I. Alekseev E. N. Bazarov Yu. A. Barannikov V. P. Gapontsev V. P. Gubin I. É. Samartsev N. I. Starostin 《Technical Physics Letters》1998,24(9):719-721
A new optical system is proposed and investigated experimentally for a Sagnac fiber interferometer in which the excess noise
of the wide-band radiation source is suppressed. A tenfold improvement in the sensitivity of a fiber-optic gyroscope with
an erbium/ytterbium fiber superfluorescent light source was achieved experimentally. It is shown that the identity of the
polarization characteristics of the interferometer channels plays an important role.
Pis’ma Zh. Tekh. Fiz. 24, 30–35 (September 26, 1998) 相似文献
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基于Allan方差对微机电陀螺的随机漂移误差进行分析和建模,并通过粒子滤波提高了微机电陀螺的零偏稳定性.实验结果表明,这种方法比较简单而切实可行,可以明显提高微机电陀螺仪的零偏稳定性. 相似文献
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A novel interferometric fiber-optic gyroscope with amplified optical feedback by an Er-doped fiber amplifier (EDFA) is proposed and theoretically investigated (the proposed gyroscope is named the feedback EDFA-FOG, FE-FOG in what follows). The FE-FOG functions like a resonant fiber-optic gyro (R-FOG) because of its multiple utilization of the Sagnac loop; however, it is completely different because a low-coherence light source is used. In addition, the gyro output signal is pulsed because the modulation frequency of the phase modulator placed in the Sagnac loop is selected to match the total round-trip time delay of the light, which includes the Sagnac-loop delay plus that of the feedback loop of the fiber amplifier. The sharpness of the output pulse can be adjusted by both the gain of an EDFA and the modulation depth of the phase modulator. When rotation occurs the peak position of the output pulse is shifted as a result of the Sagnac effect. The resolution of the rotation measurement depends on the sharpness of the output pulse. The techniques of both the open-loop and closed-loop methods are described in detail, which shows the great advantage of the proposed gyroscope over the to the conventional interferometric fiber-optical gyroscope (I-FOG). 相似文献