Convex Optimization Based LED Lamps Arrangement For Visible Light Communication

With the development of manufacturing Technology for LED and the increase of market coverage, more and more researchers participate in the research on indoor visible light communication. Visible light communication is that under the premise of providing illuminance, data information is carried by transmitted light signal simultaneously. Nowadays, the main problem in a VLC system is that power coverage on communication floor is not flat. This thesis makes an intensive research and discussion for power coverage. The finished work is as follows.Firstly, the light source plays an important role in indoor visible light communication. we introduce the basic properties of white LED light source, such as luminous intensity, lambert model, angel of half power. Among all factors influence communication performance, noise is a heavy one. So, we introduce types of the noise in indoor VLC and their fundamental characteristics. After telling the typical indoor VLC model, under the circumstance VLC has one LED transmitter, we give the distribution of received optical power on communication floor.Secondly, we model the channel in indoor VLC. During the process of moding, the concept of channel matrix is introduced to make the research convenient. Because of that if the multipath is considered, it is very difficult to calculate the channel matrix, so the recursive algorithm is applied to make it possible to calculate the component of one-reflect, second-reflect even the higher-reflect.Finally, A LED lamp arrangement scheme based on Convex optimization by reverse design is proposed to achieve approximate uniform communication performance. The ceiling is divided into 64 equal-sized squares at the center of which a LED light transmitter is placed. Then we establish communication model and transformed the problem into a Convex optimization problem. At last, a coefficient matrix is achieved by Convex optimization to design the LED arrangement schema.