Wireless infrared communication systems and networks

Wireless radio technologies have matured over a much longer time compared to wireless infrared technologies. However, as a result of their low complexity and cost, infrared technologies provide very attractive and cost-efficient wireless solutions at bit rates up to several tens of Mbps. A model for the spatial variation of infrared channels is presented, and is used to show that angle diversity can result in significant gain in link power efficiency. By using a holographic diffuser for shaping the transmitter radiation pattern, the path loss of a nondirected optical link can be reduced.