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Updated: Jun 18, 2026
09:43
Transmission of Multiple Signals through an Optical Fiber Using Wavefront Shaping
Published on: March 20, 2017
On the communication over strong atmospheric turbulence channels by adaptive modulation and coding
Ivan B Djordjevic1, Goran T Djordjevic
1Department of Electrical and Computer Engineering, University of Arizona, Tucson, AZ 85721, USA. ivan@ece.arizona.edu
Optics Express
|November 13, 2009
Summary
This study introduces a hybrid free-space optical (FSO) and wireless communication system to overcome atmospheric turbulence. The novel approach enhances spectral efficiency and tolerates deep fades for reliable high-speed data transmission.
Area of Science:
- Optical Communications
- Wireless Communications
- Signal Processing
Background:
- Free-space optical (FSO) communication offers high-speed connectivity but suffers from atmospheric turbulence-induced scintillation.
- Scintillation causes variations in signal amplitude and phase, degrading performance in FSO systems.
Purpose of the Study:
- To enable high-speed communication over atmospheric turbulence channels by proposing a hybrid FSO and wireless communication scheme.
- To maximize the total channel capacity by adapting power and rates based on channel state information.
Main Methods:
- Transmitting encoded data over both FSO and wireless channels.
- Utilizing radio frequency (RF) feedback to obtain channel state information for both FSO and wireless links.
- Deriving an optimal power adaptation policy to maximize total channel capacity.
Main Results:
- Significant improvements in spectral efficiency performance were demonstrated.
- The proposed hybrid scheme effectively tolerates deep fades of 35 dB and above.
- The derived optimal power adaptation policy maximizes the overall channel capacity.
Conclusions:
- The hybrid FSO and wireless communication scheme provides a robust solution for high-speed data transmission in turbulent atmospheric channels.
- This approach significantly enhances communication reliability and performance compared to traditional FSO systems.
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