ABSTRACT
This introductory chapter focuses on optical wireless communication systems. It discusses the disadvantages of infrared (IR) technology with the aim of having a complete overview of the technology and the possibility to compare it to radio as a medium for wireless communication. The chapter provides different system configurations and explains their advantages and limitations. IR systems can be classified according to their degree of directionality as directed, non-directed, or hybrid; and according to the existence of a line-of-sight between the transmitter and the receiver as line-of-sight (LOS) or non-LOS. Indoor wireless IR systems generally incorporate light-emitting diodes at the transmitter, due to the fact that they are inherently safe and can make use of a simple driver. Outdoor systems, on the other hand, generally employ laser diodes, which can transmit information at high data rates.
