Error compensation via signal correlation in high-precision closed-loop fiber optic gyros
Error compensation via signal correlation in high-precision closed-loop fiber optic gyros
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DOI：
10.1117/12.258182
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发表时间：
1996-11
期刊：
影响因子：
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通讯作者：
G. Spahlinger;M. Kemmler;M. Ruf;Mauricio A. Ribes;S. Zimmermann
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文献类型：
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作者：
G. Spahlinger;M. Kemmler;M. Ruf;Mauricio A. Ribes;S. Zimmermann
如果线性度和动态范围是主要考虑因素，那么光纤陀螺仪 (FOG) 最好作为闭环控制系统进行驱动。必须对萨格纳克干涉仪 (SIF) 反馈信号进行适当的调制，以最大限度地减少低频信号扰动，并可靠地检测正弦萨格纳克相位到强度映射的线性区域中的亮度强度。然而，确定性调制伴随着众所周知的“死区”以及由于调制器和光学检测器之间不可避免的串扰而导致的偏置误差。在本文中，我们提出了一种高精度闭环光纤陀螺系统，具有无差拍控制和 SIF 反馈信号的伪随机调制。随机调制原理完全消除了小旋转速率检测中的“死区”，并且具有通过信号相关性补偿和控制非理想系统中遇到的多个误差源的固有潜力。基于相关的控制原理在一般情况下被引入，并应用于所提出的闭环光纤陀螺内的一组专用控制环。从相关控制的高精度光纤陀螺的几个原型实现中获得的结果表明，偏置误差有可能减少两个数量级，并且随机游走可显着减少。
Fiber optic gyroscopes (FOGs) are preferably driven as closed-loop controlled systems, if linearity and dynamic range are of major concern. Proper modulation of the Sagnac interferometer (SIF) feedback signal is necessary to minimize low frequency signal perturbation and to reliably detect luminance intensity in the linear regions of the sinusoidal Sagnac phase to intensity mapping. Deterministic modulation however, is accompanied by well known 'dead zones' and bias errors due to unavoidable crosstalk between the modulator and the optical detector. In the paper we propose a high precision closed-loop FOG system with deadbeat control and pseudorandom modulation of the SIF feedback signal. The random modulation principle completely eliminates 'dead zones' in the detection of small rotation rates, and bears an inherent potential for compensation and control of several error sources encountered in non-ideal systems by means of signal correlation. The principle of correlation based control is introduced in a general context and applied to a set of dedicated control loops within the proposed closed-loop FOG. Results obtained form several prototype realizations of the correlation controlled high precision FOG indicate a potential for bias error reduction by two orders of magnitude and considerable decrease in random walk.