Best things in life are free! Visible Light Communication (VLC) allows high rate data transmission while illuminating. Are we going back to more than 100 years ago when Bell performed his transmissions through a photophone?
By sure, we are using the same principles.
It is sufficient to quickly switch on and off the LED light to transmit a wide bandwidth signal invisible to the human eye and completely safe for the human body.
VLC can be applied in several fields:
- In office or at home, light-fidelity (Li-Fi) can substitute or complement Wi-Fi for data download, by simply using the LED lights on the walls.
- In underwater communications, where traditional RF transmissions hardly work due the strong attenuation introduced by water and acoustic waves undergo to several limitations.
- In vehicular networks, for vehicle-to-vehicle (V2V) communications through LED lights of cars and for vehicle-to-infrastructure (V2I) communications through the traffic lights or the variable message panels.
- In sensible areas such as hospitals or airplane cabins where RF interfere with on board instrumentations.
Researchers of CNR-IEIIT deal with VLC having in mind two main objectives.
The first objective is devoted to the evaluation of VLC potential benefits in vehicular scenarios for crowd sensing applications. The information exchanged among vehicles and acquired by the infrastructure can be used to capillary monitor and map traffic conditions and pollutions and, consequently, suggest new routes to improve safety and efficiency. We can evaluate the connectivity level of the scenario with variable traffic densities and the amount of data exchanged using the sole VLC or VLC together with other RF technologies.
The second objective is the development of a low cost platform for the Internet of Things (IoT): in the next future, every device will be connected, dramatically increasing the data produced and highlighting the hunger of bandwidth. We are designing a short range and low data rate simple system that could be integrated on sensors in high density scenarios, solving the problem of interference and bandwidth unavailability.
Light is free and safe. However, VLC transmission is strongly subjected to the presence of obstacles (light does not cross obstacles) and to natural or artificial luminous interference. But VLC should be mainly seen as a complementary technology to overcome RF limitations and this is the direction we are taking to develop our systems.
info: Barbara.Masini@ieiit.cnr.it
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