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Adaptive optical transmitter and receiver for space communication through thin clouds.
Applied Optics
|March 20, 1997
Summary
Adaptive optical communication systems mitigate cloud-induced pulse broadening. By modeling the atmospheric channel, systems adapt parameters, enabling satellite-to-ground communication despite signal degradation.
Area of Science:
- Optical communication
- Atmospheric physics
- Signal processing
Background:
- Clouds significantly impact optical space communication by widening and attenuating optical pulses.
- Pulse broadening in the time domain limits information bandwidth in satellite-to-ground links.
- Previous research addressed other atmospheric effects, necessitating focus on pulse broadening.
Purpose of the Study:
- To develop a mathematical model for adaptive optical communication systems operating through clouds.
- To investigate methods for adapting transmitter and receiver parameters to cloud channel characteristics.
- To analyze the performance of adaptive systems in satellite-to-ground communication scenarios.
Main Methods:
- Derivation of a mathematical model for an adaptive optical communication system.
- Utilizing the impulse response function of the cloud to adapt system parameters.
- Modifying transmitter bit error rate and receiver detector/filter parameters for adaptation.
- Comparing adaptive and semi-adaptive systems through practical examples.
Main Results:
- A model was developed to adapt optical communication parameters to cloud channel transfer functions.
- Adaptation strategies for both transmitter and receiver were defined.
- Analysis showed adaptive methods are crucial for maintaining communication through clouds.
- Practical examples demonstrated system feasibility between LEO satellites and ground stations.
Conclusions:
- Adaptive optical communication is essential for reliable satellite-to-ground links through clouds.
- System parameter adaptation based on channel knowledge significantly improves performance.
- In challenging cloud conditions, adaptive techniques may be the only viable solution for optical communication.
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