Document Type : Original Research Paper


1 Optical Communications Research Group, Faculty of Engineering and Environment, Northumbria University, Newcastle Upon Tyne, UK

2 Ecole Centrale Marseille, Institute Fresnel, Marseille, France

3 Department of Electronic Engineering, Tsinghua University, Beijing, China


For an indoor non-directed line of sight optical wireless communication (NLOS-OWC) system we investigate the optimized Lambertian order (OLO) of light-emitting diodes (LEDs). We firstly derive an expression for the OLO from a conventional Lambertian LED model. Then, we analyze the indoor multi-cell NLOS-OWC channel characteristics including the optical power distribution and the multipath time dispersion for two cases of one-cell and four-cell configurations. Furthermore, we estimate the transmission bandwidth by simulating the channel frequency response. Numerical results presented show that, by using OLO a significant improvement of the transmission bandwidth can be achieved for an indoor NLOS-OWC system, in particular, for multi-cell configurations.


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