Optical spatial modulation OFDM using micro LEDs

This paper investigates the performance of optical spatial modulation (OSM) with orthogonal frequency division multiplexing (OFDM) in a multiple-input and multiple-output (MIMO) based visible light communication (VLC) system. Gallium nitride micro light emitting diodes (μLEDs) are used as transmitters. The performance of the OSM-OFDM system is analyzed as a function of the spatial separation, d_s and the half-power semi-angle, φ_1/2 of the transmitter μLEDs. OSM-OFDM is compared with a standard optical spatial multiplexing (OSMX) OFDM system. The achievable data rate and the computational complexity are considered as performance metrics. The simulation results show that OSMX-OFDM can achieve higher data rates than OSM-OFDM. At the same time, however, OSM-OFDM attains a significantly lower BER and computational complexity than OSMX-OFDM.