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Microwave Photonics Systems Based on Whispering-gallery-mode Resonators
Published on: August 5, 2013
Dynamic instabilities of microwaves generated with optoelectronic oscillators
Y Kouomou Chembo1, Laurent Larger, Hervé Tavernier
1UMR CNRS FEMTO-ST 6174, Département d'Optique P. M. Duffieux, Université de Franche-Comté, 16 Route du Gray, 25030 Besançon Cedex, France. yanne.chembo@femto-st.fr
Optics Letters
|September 4, 2007
Summary
Instability in optoelectronic oscillators arises from nonlinearity and time delay. Increasing gain beyond a critical point destabilizes microwave generation, confirmed by simulations and experiments.
Area of Science:
- Physics
- Electrical Engineering
- Optoelectronics
Background:
- Optoelectronic oscillators (OEOs) are crucial for generating high-frequency signals.
- Understanding the dynamic stability of OEOs is essential for their reliable operation.
- Nonlinearity and time delay are inherent characteristics of OEOs that influence their dynamics.
Purpose of the Study:
- To develop a time-domain model for analyzing OEO dynamics.
- To investigate the conditions leading to instability in OEOs.
- To understand the role of nonlinearity and time delay in OEO stability.
Main Methods:
- Development of a novel time-domain model.
- Analytical investigation of system dynamics.
- Numerical simulations to validate model predictions.
- Experimental verification of theoretical findings.
Main Results:
- The study reveals that increased gain beyond a critical value can lead to instability.
- The interaction between nonlinearity and time delay is identified as the primary cause of instability.
- Envelope amplitude of generated microwaves becomes unstable under specific conditions.
Conclusions:
- The developed time-domain model accurately predicts OEO dynamics.
- Nonlinearity and time delay are critical factors governing OEO stability.
- The findings provide insights for designing more stable OEOs.
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