Development of an open-loop fiber optic gyroscope system and relative intensity noise analysis

Fiber optic gyroscope systems are widely used in applications requiring high precision and accuracy, such as military platforms, aviation, and navigation systems. This thesis focuses on the development of an open-loop fiber optic gyroscope system and the analysis of relative intensity noise in these systems. A navigation-grade fiber optic gyroscope system was established in an experimental and simulation environment and the obtained results were examined. The established fiber optic gyroscope system has approximately 1 km of fiber coil and the simulation studies were optimized by the experimental system. Simulation studies were performed using VPI Photonics software. VPI Photonics offers a powerful simulation platform for the design and analysis of optical and photonic systems. In this study, amplified spontaneous emission light source designs, widely used in fiber optic gyroscopes, were established, and simulation and experimental results with different configurations were examined. The effects of varying light source designs on relative intensity noise were also investigated. In these analyses, the impact of the optical spectral bandwidth of the light source on the noise level was investigated and the obtained results were supported by theoretical calculations. Then, an open-loop fiber optic gyroscope design was built, and simulation and experimental system models were prepared. In order to detect the Earth's rotation speeds, measurements were made between 0 degrees/hour and 15 degrees/hour according to different angular positioning of the sensor unit, and the obtained results were analyzed. It was observed that the experimental Earth rotation tests performed on the optical table in the laboratory environment and the simulation model results were largely similar. Later, studies were carried out to improve the angular random walk coefficient, which is a value that determines the performance of the fiber optic gyroscope. One of the most important factors affecting this value is the relative intensity noise of the light source in the system. An innovative light source design was made using semiconductor optical amplifiers to reduce the relative intensity noise affecting the performance of fiber optic gyroscope systems and its effects on the system performance were investigated. The tests of the light source without noise reduction and the light source with reduced noise level were carried out by collecting long-term data in the laboratory environment and the obtained results were analyzed and significant improvements were made in the performance of the fiber optic gyroscope system.