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Mobile User Connectivity in Relay-Assisted Visible Light Communications.

Petr Pešek1, Stanislav Zvanovec2, Petr Chvojka3

  • 1Department of Electromagnetic Field, Faculty of Electrical Engineering, Czech Technical University in Prague, 2 Technicka, 16627 Prague, Czech Republic. pesekpe3@fel.cvut.cz.

Sensors (Basel, Switzerland)
|April 13, 2018
PubMed
Summary

Mobile users can act as relays in visible light communications (VLC) using amplify-and-forward (AF) and decode-and-forward (DF) schemes. DF relaying offers improved coverage for mobile VLC systems.

Keywords:
amplify-and-forward relayingcooperative communicationdecode-and-forward relayingvisible light communications

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Area of Science:

  • Wireless Communications
  • Optical Communications
  • Mobile Computing

Background:

  • Visible Light Communications (VLC) offers high-speed wireless data transmission using LED lighting.
  • Mobile devices can potentially enhance VLC network coverage and reliability.
  • Relaying schemes are crucial for overcoming signal obstructions in wireless networks.

Purpose of the Study:

  • To analyze the performance of relay-assisted VLC systems where a mobile user acts as a relay.
  • To investigate the effectiveness of amplify-and-forward (AF) and decode-and-forward (DF) relaying schemes in a mobile VLC context.
  • To evaluate the impact of mobile relay device orientation and environment on bit error rate (BER) performance.

Main Methods:

  • Analytical modeling of BER for AF and DF relaying in VLC with realistic mobile phone receiver/transmitter configurations.
  • Simulation of system performance considering mobile relay device's azimuth and elevation angles in an office environment.
  • Comparison of relay-based VLC systems against direct non-line-of-sight (NLOS) links.

Main Results:

  • A new analytical description for BER in AF and DF-based VLC relays is presented.
  • Decode-and-forward (DF) provides a marginal improvement in coverage area (BER < 10^-3, data rate 100 Mb/s).
  • Relay-assisted VLC significantly enhances coverage compared to direct NLOS VLC links.

Conclusions:

  • Mobile users can effectively serve as relays in VLC systems, improving communication reliability.
  • DF relaying scheme demonstrates superior performance in terms of coverage extension for mobile VLC.
  • Relay-based VLC presents a viable solution for expanding coverage in non-line-of-sight scenarios.