| PhD Seminar

Name of the Speaker: Ms. Sumathi M (EE17D054)
Guide: Dr. Balaji Srinivasan
Online meeting link: https://meet.google.com/kjh-xqza-gck
Date/Time: 30th April 2025 (Wednesday), 11 AM
Title: Role of coherence in determining bias stability of Resonant Fiber Optic Gyroscope (RFOG) for Navigation Applications

Abstract :

Bias stability is a critical performance parameter in navigation applications. During the last decade, substantial progress has been made to increase the bias stability of fiber optic gyroscopes for their use in inertial navigation applications. Specifically, the Resonant Fiber Optic Gyroscope (RFOG) configuration is attractive due to their compact size and potentially lower susceptibility to environmental variations.

In this research, an experimental study on the role of coherence is carried out to enhance the bias stability parameter determination in RFOG. We propose an alternative approach based on a frequency comb source. By using different set of frequencies (3, 5, 7, 9 etc) for the counter-propagating waves, the above limitations can be mitigated since the uncertainty in the demodulated phase is diminished owing to simultaneous measurement at multiple frequencies compared to a single frequency measurement, leading to enhanced accuracy in the rotation rate determination. However, the frequency locking loop is required to track the RFOG resonance with the different set of frequencies which increases the RFOG system complexity.

Further study is carried out the use of low coherence SLD source with frequency locking free mechanism based on the round trip filtering method in the fiber ring resonator. In this seminar, we will discuss the challenges for achieving the bias stability and investigate the role of coherence in the RFOG configuration and compare the performance parameter with Interferometric fiber optic gyroscope (IFOG). Also demonstrated the bias stability < 0.1 ⁰/hr using 20 m fiber length in the resonant fiber optic gyroscope for inertial navigation applications