High-precision indoor three-dimensional positioning system based on visible light communication using modified artificial fish swarm algorithm

Indoor visible light positioning has become a research hotspot owing to its high accuracy, low cost, and easy implementation. However, many existing indoor positioning systems based on visible light communication (VLC) can only achieve two-dimensional (2-D) positioning and those focusing on three-dimensional (3-D) positioning usually contain various sensors or use complex algorithms. Consequently, a high-precision indoor 3-D positioning system based on VLC using modified artificial fish swarm algorithm is proposed, avoiding the problems mentioned above. To simplify the solution procedure of searching for 3-D coordinates, the 3-D positioning problem is transformed into a global optimization problem with the corresponding fitness function designed according to Lambertian radiation pattern. The simulation executed on 1350 points shows an average 3-D positioning error of 4.05 mm in an indoor space of 4 m x4 m x6 m, and 90% positioning errors are below 5.95 mm. Moreover, when tracking a moving target in the positioning space, the average error is 3.57 mm and the maximum error is 7.25 mm. All in all, the system proposed in this paper stands a good chance of widespread application for its excellent performance in indoor 3-D positioning. (C) 2018 Society of Photo-Optical Instrumentation Engineers (SPIE)