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Spatial decoherence compensation algorithm for a target speckle field in heterodyne detection based on frequency
Optics Express
|November 23, 2021
Summary
A new spatial decoherence compensation algorithm overcomes laser speckle issues in heterodyne lidar. This method significantly enhances signal-to-noise ratio and enables real-time processing for improved long-distance target detection.
Area of Science:
- Optics and Photonics
- Laser Technology
- Remote Sensing
Background:
- Laser speckle fields induce decoherence, limiting heterodyne lidar performance.
- This decoherence effect hinders the development of advanced lidar systems.
Purpose of the Study:
- To develop and validate a spatial decoherence compensation algorithm for heterodyne lidar.
- To improve the signal-to-noise ratio (SNR) and enable real-time processing.
Main Methods:
- Proposed a novel spatial decoherence compensation algorithm.
- Conducted experimental validation using a simple and operable system.
Main Results:
- Demonstrated experimental feasibility of the proposed algorithm.
- Achieved a processing speed several orders of magnitude higher than existing methods.
- Increased system SNR by up to 1464 times post-processing.
Conclusions:
- The algorithm effectively compensates for spatial decoherence in heterodyne lidar.
- Real-time processing capability makes it suitable for practical applications.
- Significant potential for long-distance weak target detection using lidar technology.
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