| Fiber optic gyroscopes (FOGs) have been in existence for over 20 years, and have shown promise in high-precision inertial navigation systems for the guidance of airplanes. In order to achieve inertial grade performance, a reduction in both the current levels of FOG noise and drift is still required. To that end, employing a laser source is desirable, but the fiber backscattering noise and Kerr effect drift first have to be suppressed.; In this dissertation, I will present my work on the use of an air-core photonic-bandgap fiber (PBF), in the sensing loop of a laser-driven FOG. I will first introduce a versatile full-vectorial finite-difference solver for PBF modes, allowing their quick and accurate determination on a personal computer.; Next, I will show experimentally that the long-term drift in a laser-driven PBF FOG is reduced, when compared to a conventional FOG. The thermal sensitivity of the PBF FOG is found to be reduced by a factor of 6.5, while its nonlinear drift is determined to be negligible.; Finally, I will address the short-term noise of the laser-driven PBF FOG, and determine experimentally the backscattering coefficient of the PBF, which is determined to be 10 times larger than in an SMF-28 fiber. I will however show that, in the regime where PBF loss is limited by frozen-in surface capillary waves, the backscattering coefficient of the PBF can be significantly reduced from its current level. Under these conditions, I will demonstrate, through numerical simulations, that the inertial navigation of an airplane under the sole guidance of a laser-driven PBF FOG should be possible, with an accuracy satisfying the FAA's RNP-10 criterion, for at least 10 hours. |
