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Space-frequency coded orthogonal signal-division multiplexing over underwater acoustic channels
Jing Han1, Wentao Shi1, Geert Leus2
1School of Marine Science and Technology, Northwestern Polytechnical University, Xi'an 710072, China hanj@nwpu.edu.cn, swt@nwpu.edu.cn.
The Journal of the Acoustical Society of America
|June 17, 2017
Summary
A novel space-frequency block coding (SFBC) scheme using orthogonal signal-division multiplexing (OSDM) improves performance in time-varying underwater acoustic channels compared to SFBC-OFDM.
Area of Science:
- Signal Processing
- Underwater Communications
- Wireless Networking
Background:
- Orthogonal signal-division multiplexing (OSDM) unifies existing modulation techniques.
- Underwater acoustic channels present significant challenges due to time-varying conditions.
Purpose of the Study:
- To propose a novel space-frequency block coding (SFBC) scheme based on OSDM.
- To enhance communication reliability in time-varying underwater acoustic environments.
Main Methods:
- Developed an SFBC scheme utilizing OSDM for underwater acoustic channels.
- Implemented receiver processing including Doppler compensation, channel estimation, SFBC decoding, and equalization.
Main Results:
- The proposed SFBC-OSDM scheme demonstrated superior performance.
- Outperformed the conventional SFBC-OFDM approach in simulations and experiments.
Conclusions:
- SFBC-OSDM is a promising technique for robust underwater acoustic communications.
- Offers significant advantages over existing SFBC-OFDM methods in challenging channel conditions.
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