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Error performance of an L-PPM modulated ADR-based MIMO-VLC system with and without channel estimation error
Applied Optics
|May 3, 2023
Summary
This study introduces a multiple-input multiple-output visible light communication (MIMO VLC) system using L-pulse position modulation (L-PPM). The research highlights that channel estimation error significantly degrades performance, even with increased signal-to-noise ratio.
Area of Science:
- Wireless communication technologies
- Optical communication systems
Background:
- Visible Light Communication (VLC) is a key technology for future beyond 5G networks.
- Multiple-Input Multiple-Output (MIMO) configurations enhance wireless communication capacity.
- Pulse Position Modulation (PPM) is a modulation scheme used in optical wireless systems.
Purpose of the Study:
- To propose and analyze a MIMO VLC system utilizing L-pulse position modulation (L-PPM).
- To evaluate the system's performance under varying channel estimation error (CEE) conditions.
- To compare the effectiveness of different receiver diversity techniques.
Main Methods:
- Implementation of an angular diversity receiver (ADR) for the MIMO VLC system.
- Application of repetition coding (RC) at the transmitter.
- Employment of receiver diversity techniques: maximum-ratio combining (MRC), selection best combining (SBC), and equal gain combining (EGC).
- Derivation of exact probability of error expressions, considering channel estimation error.
Main Results:
- The probability of error escalates with increasing channel estimation error.
- Enhanced signal-to-noise ratio is insufficient to overcome significant estimation errors.
- Performance degradation due to CEE is more pronounced with larger estimation errors.
- Spatial distribution of error probability was analyzed for EGC, SBC, and MRC.
Conclusions:
- The proposed MIMO VLC system's performance is sensitive to channel estimation accuracy.
- Receiver diversity techniques offer performance improvements, but CEE remains a critical factor.
- Analytical results were validated against simulation findings, confirming the system's behavior.
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