Ricerc@Sapienza

Visible Light Communication is considered one of the most promising solutions to provide wireless connectivity in indoor scenarios. Furthermore, the simultaneous support of illumination and communication services makes such technology perfectly suited to the paradigm of smart environments. Data
communication is obtained by modulating the optical signal emitted by a Light Emitting Diode. Taking advantage of spatial diversity, multiple sources can be also employed to improve the transmission rate.
However the arising co-channel interference, if not properly tackled, may significantly impact on the system reliability. In this direction, in this project entitled "Optical Wireless Modulation Constellation Optimization" (OWMCO) , we aim at investigating a Multiple-Input Single-Output scenario where sources
emit spatially multiplexed, Pulse Amplitude Modulated signals. Having the receiver as equipped with a single photodetector makes signals separation and decoding very challenging, especially when channels are correlated. To this aim, the goal of this project is to propose novel modulation precoding schemes, relying on adaptive power allocation, that consider co-channel interference as a parameter to be minimized by possibly maximizing the minimum Euclidean distance between received symbols. Such techniques are expected to lead to a joint optimal constellation design and channel equalization lowering the symbol error probability while meeting the illumination constraints as well.