Impact of LED Array Simplification on Indoor Visible Light Communication Channel Modeling

Indoor visible light communication (VLC) techniques are expected to utilize LED based infrastructure to provide data transmission and general illuminance. To ensure full coverage of a lighting area, multiple LED lamps must be employed. Each lamp consists of an array of LEDs. In typical VLC channel modeling, each array is usually treated as a single point source. This simplification offers very low computational complexity, but may lead to modeling inaccuracy in some cases. This paper compares different LED array approximation schemes in terms of channel characteristics. Either the actual structure of each array or an approximated constellation is considered. Signals from different sources undergo multiple reflections up to certain order. Numerical results show that different models give almost similar received optical power distribution across the lighting area, but significantly different average root mean square delay spread profile and thus channel bandwidth in the investigated cases.