Shi C X, Yuhara T, Iizuka H, Kajioka H
Appl Opt. 1996 Jan 20;35(3):381-7. doi: 10.1364/AO.35.000381.
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).
提出了一种采用掺铒光纤放大器（EDFA）进行光反馈放大的新型干涉式光纤陀螺仪，并对其进行了理论研究（以下将所提出的陀螺仪称为反馈式EDFA-FOG，简称FE-FOG）。由于FE-FOG多次利用了萨尼亚克环，其功能类似于谐振式光纤陀螺仪（R-FOG）；然而，由于使用了低相干光源，二者又完全不同。此外，由于选择置于萨尼亚克环中的相位调制器的调制频率与光的总往返时间延迟相匹配，陀螺仪输出信号呈脉冲状，该总往返时间延迟包括萨尼亚克环延迟加上光纤放大器反馈环的延迟。输出脉冲的锐度可通过EDFA的增益和相位调制器的调制深度进行调节。当发生旋转时，由于萨尼亚克效应，输出脉冲的峰值位置会发生偏移。旋转测量的分辨率取决于输出脉冲的锐度。详细描述了开环和闭环方法的技术，这表明所提出的陀螺仪相对于传统干涉式光纤陀螺仪（I-FOG）具有很大优势。
