Section: New Results

Visible Light Communication

Participants : Antonio Costanzo, Valeria Loscri.

Visible Light Communication (VLC) exploits optical frequencies, diffused by usual LED lamps, for adding data communication features to illuminating systems. This paradigm has attracted a growing interest in both scientific and industrial community in the latter decade. Nevertheless, classical wireless communication mechanisms for physical and Medium Access Control (MAC) layers are hardly available for VLC, due to the massive external interference caused by sunlight. Moreover, effects related to the data frames features need to be taken into account in order to improve the effectiveness of the VLC paradigm. Such as an instance, the preamble length of a packet in order to synchronize the data transmission represents an important factor in VLC. A too long preamble allows a better synchronization while impacting negatively in terms of overhead. Nevertheless, a too short preamble may be not effective for synchronizing the transmission. The more suitable selection of the preamble length is strictly related to the noise environments. In order to make an adaptive selection able to choice the more suitable preamble length, we have designed and integrated in our VLC system a machine learning algorithm based on multi-arm bandit approach, in order to dynamically select the best configuration [28]. Another important approach to face the high interference impacting on the VLC performance is represented by the treatment of the noise through a signal processing approach in order to estimate it and proceed with a mitigation of the noise [10], [29], [36], [30]. This approach has been implemented and tested by the means of a real prototype. Results obtained show the effectiveness of a similar approach.