Coverage uniformity with improved genetic simulated annealing algorithm for indoor Visible Light Communications

Indoor visible light communication (VLC) based on light-emitting diodes (LED) can meet needs of illuminance and high-rate communication. However, the distributions of optical power and illuminance intensity on the receiving plane are nonuniform owing to the Lambertian emission pattern and inherent multipath diffuse channel characteristics. To reduce the power fluctuation and improve the fairness, an improved genetic simulated annealing algorithm (IGSAA) is proposed to search a set of optimal power factors (PF) quickly without changing LED layouts and LED location in this paper. In IGSAA, fitness function is designed in the view of the differences of received power among different positions on receiving plane. Based on the information of optimal chromosome and evolutional generation, two-point crossover operation and dynamic mutation probability are designed for speeding up search coverage. Besides, to maintain the diversity of population, Metropolis criterion is introduced to accept chromosomes in each generation of IGSAA. Numerical results show that the proposed IGSAA can effectively improve the coverage uniformity of indoor VLC communications within limited generations.