Resonator Fiber Optic Gyroscope with Active Gain Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Resonator fiber optic gyros face challenges in achieving low cost and high performance due to increased component losses and component aging, which affect sensitivity and stability, particularly in maintaining a constant round-trip loss while coupling high optical power to detectors.
Innovation Solution
Incorporating optical gain elements and variable optical attenuators within the resonator to adjust and maintain a substantially constant positive round-trip loss, utilizing pump lasers to control the gain elements, and employing optical filters to suppress noise, ensuring efficient light amplification and reduced shot noise.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If longer fiber length is used to reduce resonance linewidth, then sensitivity is improved, but cavity round trip loss increases
Solution Approach 1:
The patent changes the parameter of fiber length to optimize sensitivity while managing the associated increase in round trip loss through active compensation mechanisms
2Stability of the object's composition
If polarization and spatial mode filters are added to prevent bias instability, then measurement stability is improved, but device complexity increases
Solution Approach 1:
The patent applies filtering selectively at specific locations within the resonator where it is most effective, rather than uniformly throughout the entire system
3Object-affected harmful factors
If high coupling losses are used to output more optical power to detectors, then shot noise is reduced, but resonator finesse decreases
Solution Approach 1:
The patent employs active feedback control to monitor and adjust the coupling losses in real-time, maintaining optimal balance between power output and finesse
Solution Approach 2:
The system transitions from static coupling parameters to dynamic, adjustable coupling losses that can be optimized for different operating conditions
4Reliability
If ultra-low-loss components are used to reduce round trip loss, then resonator finesse is improved, but manufacturing cost increases
Solution Approach 1:
The patent uses standard, commercially available components with moderate loss characteristics, compensating for their higher loss through active gain elements rather than requiring expensive ultra-low-loss components
Solution Approach 2:
Optical gain elements are introduced as intermediary components that compensate for losses in standard components, enabling the use of cheaper parts while maintaining high finesse
5Device complexity
If component aging is allowed to occur, then device simplicity is maintained, but round trip loss increases over time
Solution Approach 1:
The control system continuously monitors round trip loss and adjusts gain element pumping to compensate for aging-induced losses, maintaining stable performance over time
Solution Approach 2:
The system automatically compensates for its own degradation through the feedback control mechanism, eliminating the need for manual intervention or replacement of aging components
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This approach maintains a high resonator finesse, reduces shot noise-induced angle random walk, and relaxes component loss specifications, enabling low-cost, high-performance gyroscope operation with improved stability and reduced power dissipation.
Implementation Method 1
one or more optical gain elements that provide amplification of light to offset part of the losses of the resonator
Implementation Method 2
one or more pump lasers to produce one or more pump beams for the gain elements in the resonator
Implementation Method 3
one or more variable optical attenuators (VOAs) that can adjust the loss of the resonator with fast response
Implementation Method 4
one or more optical filters that suppresses the noise light in the resonator
Implementation Method 5
The resonance tracking electronics are configured to determine a rotation rate of the optical fiber resonator based on the signals from the first and second detector
Data Source
AI summary
One embodiment is directed to a resonator fiber optic gyroscope (RFOG). The optical fiber resonator includes an optical fiber, one or more optical filters that suppresses the noise light in the resonator, one or more variable optical attenuators (VOAs) that can adjust the loss of the resonator with fast response, and one or more optical gain elements that provide amplification of light to offset part of the losses of the resonator. The RFOG also includes one or more pump lasers to produce one or more pump beams for the gain elements in the resonator and control electronics configured to control the one or more pump lasers and the one or more variable optical attenuators, such that the round-trip loss of the resonator is a substantially constant, positive value.