Evaluation of Diversity Techniques for the Indoor Diffuse Infrared Channel

Infrared communication has been recently reconsidered as an alternative to microwave radio used by WLAN devices, suitable for specific applications such as hospitals or industrial communication in the presence of strong electromagnetic fields. The design of a system able to communicate efficiently even without line of sight (LOS) and in the presence of fading represents a challenging issue for a wider utilization of IR. The growing interest in the field of radio communication towards MIMO systems has encouraged few researchers to use similar techniques to fight fading effects of the diffuse infrared channel. As a first step in the design of an infrared node for diffuse communication the authors developed a complete simulation framework to evaluate the performance of diversity techniques for IR. The authors also introduce a blind channel estimator for IR MIMO receivers. Results show that diversity leads to consistent performance improvements for the IR channel in the presence of fading.