Performance analysis of mobile optical wireless systems employing a novel beam clustering method and diversity detection

User mobility in a diffuse optical wireless (OW) system is of particular interest as it can induce link performance degradations. While much attention has been given in the literature to the conventional indoor diffuse optical wireless system, little has been done in terms of evaluating the impact of user mobility in such an environment. Furthermore, there is a clear need for methods that can be used to reduce the link performance degradations attributed to user mobility. The paper considers a mobile OW system under the constraints of ambient light noise and multipath distortion. Moreover, the authors propose an original beam-clustering method (BCM) that utilises a spot diffusing technique and evaluate the associated channel characteristics. The performance of a mobile OW BCM system is analysed and compared with that of the conventional diffuse system (CDS) in a middle-sized room at 14 receiver locations. Our results indicate that, at the worst communication link, BCM can reduce the signal delay spread by nearly a factor of six and increase the SNR by >30 dB over the CDS SNR, while resulting in improved performance over all links.

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