Efficient and accurate ray tracing method for indoor radio wave propagation prediction in presence of human body movement

Due to the attractive features of millimeter band, its uses are greatly expanding in the indoor wireless communication systems. As the distance between the transmitter and receiver is much shorter in indoor environments than that of the outdoor environments, the radio wave paths of the millimeter band frequencies are highly influenced by the building materials as well as by the human movements. Ray tracing is widely used method to characterize the radio wave propagation for the planning and establishment of the indoor wireless network. Precise object modeling for the real environment and computational burden are the two classical problems of the propagation model. Because, large number of rays that travels in a complex and convoluted indoor environment must be traced. Therefore, an accurate and efficient ray tracing method is proposed here, which is based on the surface separation, object address distribution, and surface skipping techniques. The proposed approach considers the effects of human body movement to provide a realistic estimation of the wave propagation. Hence, an approximated human body model is used to simulate the activities of humans, whereas three-dimensional (3-D) cube or cuboids are used for the remaining objects of the simulation environment. To prove the superiority, complexity analysis and detailed comparisons between the proposed and existing methods are presented in this paper. The results obtained will be of great interest for the proposed ray tracing method that involves human motion within the simple and complex indoor environments.