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Published on: February 12, 2013
Coherent optical link through the turbulent atmosphere.
Khelifa Djerroud1, Ouali Acef, André Clairon
1LNE-SYRTE, Observatoire de Paris, CNRS, UPMC, 61 av. de l'Observatoire, 75014 Paris, France.
Optics Letters
|May 4, 2010
Summary
Researchers established a 5 km free-space coherent optical link through atmospheric turbulence. The link
Area of Science:
- Optical physics and atmospheric science.
Background:
- Free-space optical links are crucial for modern communication and sensing.
- Atmospheric turbulence and mechanical vibrations pose significant challenges to link stability and performance.
Purpose of the Study:
- To demonstrate a long-distance free-space coherent optical link.
- To characterize the phase noise and identify its sources in such a link.
- To explore the potential applications of this technology.
Main Methods:
- Established a 5 km free-space coherent optical link between a telescope and a ground target.
- Measured and analyzed the phase noise of the optical signal transmitted through the turbulent atmosphere.
- Investigated the contributions of atmospheric turbulence and mechanical vibrations to the overall phase noise.
Main Results:
- Successfully realized a 5 km free-space coherent optical link.
- Identified atmospheric turbulence and mechanical vibrations as the primary sources of phase noise.
- Quantified the phase noise characteristics of the link.
Conclusions:
- The developed free-space coherent optical link is feasible over significant distances despite atmospheric challenges.
- Understanding and mitigating phase noise is critical for practical applications.
- The technology shows promise for satellite optical Doppler ranging and long-distance frequency transfer.
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