Research on uniform illumination distribution of indoor visible light communication

For the problem of indoor visible light communication fairness, a constrained least squares method is proposed to generate a uniform power distribution by optimizing the beam angle and power weight of the light-emitting diodes sources. The improved Fibonacci uniform allocation procedure is employed to determine the position of the sources. The initial power of the sources is constant, and the average value of the received optical power is taken as the target power matrix of the least squares method. The element range of the power distribution weight matrix is set according to the limit of the actual light source power adjustment, and the power of the light source is redistributed to improve the signal uniformity in the receiving surface. The simulation results show that the proposed method can improve the uniformity of the received power and the signal-noise ratio in the room. And the relative standard deviation (RSD) between the received and target power is less than 0.1. When the number of the light sources is constant, the semi-angle at the half power of the sources is optimized so that the RSD value is minimum.