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Angular misalignment contribution to practical heterodyne lidars in the turbulent atmosphere
Optics Express
|May 28, 2009
Summary
Simulating beam propagation reveals heterodyne lidar sensitivity to misalignment in turbulent atmospheres. Realistic instrument performance differs from ideal models, especially at shorter wavelengths.
Area of Science:
- Atmospheric optics
- Remote sensing technology
- Optical engineering
Background:
- Heterodyne lidar systems are crucial for atmospheric measurements.
- Refractive turbulence can significantly impact lidar performance.
- Instrument misalignment is a practical concern in real-world deployments.
Purpose of the Study:
- To investigate the sensitivity of heterodyne lidar to misalignments under refractive turbulence.
- To compare the performance of realistic lidar instruments with ideal monostatic and bistatic models.
Main Methods:
- Utilizing beam propagation simulations.
- Analyzing performance under general atmospheric conditions.
- Considering shorter wavelengths for evaluation.
Main Results:
- Heterodyne lidar performance is sensitive to misalignments when refractive turbulence is present.
- Realistic instrument performance deviates from ideal monostatic and bistatic arrangements.
- Shorter wavelengths exacerbate the impact of misalignment.
Conclusions:
- Ideal lidar models are insufficient for describing realistic instrument performance in turbulent environments.
- Misalignment effects must be carefully considered in heterodyne lidar design and operation.
- Further research into robust lidar configurations is warranted.
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