Research On Visible Light Communication Positioning Technology And Light Source Layout Optimization

Visible light communication is a new green communication technology which use white LED to illuminate and communicate. It has many advantages such as broad coverage, saving energy, good safety, directional radiation, simple layout, low cost and good electromagnetic compatibility. The new indoor positioning technology based on visible light communication has the advantage that traditional indoor wireless positioning technology can’t replace. So it has a good prospect and becomes a hot topic in the field recently.Based on the typical visible light communication indoor wireless positioning model, this paper works on the optimization of the light source layout. The main contents and innovations are as follows:1. Aiming at typical visible light communication indoor wireless positioning model, the performance bound for indoor measured plane positioning error distribution(Cramer-Rao lower bound) is derived, and the best light source layout which has the least positioning error is given. Under the premise of meeting indoor lighting requirements, the Cramer-Rao lower bound of every measured point is calculated in different light source layout, and the best light source layout is given in theory. By using Gauss- Newton algorithm, some simulations are done to prove the accuracy of the Cramer-Rao lower bound based on the former work. The result shows that the obtained light source layout has a better positioning performance than the other layouts.2. The influence of the first reflection is analyzed. Aiming at the first reflection, the characteristics of the reflected channel is considered in both simple and complex conditions. Based on the simple condition, the illumination distribution of the measured plane and the Cramer-Rao lower bounds of every measured point are calculated. At the same time, the influence of the first reflection is analyzed which provides a guide to the visible light source layout with first reflection.3. Aiming at different demands of illumination and positioning, joint optimization of the light source layout is carried out. Concerning about many application demands in different applied environment, four optimization methods are adopted to solve the problem. By contrasting and analyzing the performance of the targets, the demands of both illumination and positioning could be satisfied, and the performance of each method is simulated through experiments.4. Aiming at the current situation of our laboratory under the colliery, a new method which is suitable to be used in colliery, subway, tunnel, corridor and so on is put forward. Some practical applications which use the proposed light source layout and positioning algorithm in the colliery information system are introduced at last.