LED CommunicationFor Short Range Wireless

With the huge development of semiconductor lighting technologies, the light emitting diodes (LEDs) are promising technology that eventually replacing traditional incandescent and fluorescent lamps for their high power efficiency, environmental friendliness and long predicted product lifetime. Besides lighting, the advent of high-brightness, fast-switching LED lamps has facilitated LED Communication as a new form of Optical Wireless Communication (OWC) in the visible light spectrum. This thesis study model characteristics of LED communication for indoor optical environment. Based on Matlab and SPICE, an electrical and optical LED communication model is proposed to describe light power's conversion and propagation. In details, our models include (1) models for V-I characteristics and fro small signal behavior, (2) electro-electrical conversion and emitting, (3) optical channel with path loss and noise, (4) receiving model. Moreover, a test and measurement platform for LED communication has been established to validate the proposed model. A case of study on light power distribution within 30cmX30cmX10cm in line-of-sight was implemented by measuring for comparing the theoretical simulation and experimental results. Depending on our model and the case of study, we carried out an inspection of the LED communication performance using On-Off Keying (OOK) signals and a 500 kbps transmission data rate under 10e-3 BER was achieved in our lab