Prediction Of Indoor Radio Propagation And Its Application In PHS Indoor Distribution System

In recent years, indoor wireless communication systems and practical applications have been a very active area of research. Effective designing, assessment, and installation of a radio network in an indoor environment require an accurate characterization of radio propagation channel. The paths of radio wave propagation between transmitter and receiver are determined through transmission, reflection, and diffraction mechanisms. For complex lossy structures encountered in indoor environment, the propagation behavior in any in-building environment is a difficulty to predict phenomenon which depends evidently on building structure and operating frequency.The ray tracing technique has been demonstrated to be promising for indoor radio propagation modeling by many researchers. But for the complicated conditions, long calculation time is a difficulty to its practical usage. So a applicable solution should be found out. Based on Image Theory and tube-tree method, an applicable ray tracing method based on virtual source tree was presented in this paper. The definition of the reflection source and diffraction source in the tree structure makes the ray tracing course more simple and efficient. Furthermore, the original source and receiving point are also added to the tree structure. By searching the whole tree structure, all the available propagation path from transmitter to receiver can be found out. And the computation is also more convenient and efficientThe FDTD method is a relatively mature method, which provides a effective technique for the modeling of a field distribution inside a room. By directly solving Maxwell's equations in the time domain, FDTD method fully accounts for the effects of reflection, diffraction, and radiation. So in this paper, a software called XFDTD, which is based on FDTD method, is used to model the indoor radio propagation. And the results obtained from FDTD are also compared with the results obtained from ray tracing before.At last, the ray tracing modeling is applied to the actual PHS indoor distribution system project. By comparing the predicted results are also with the measurement result, the validity of the ray tracing method is verified.