Research Of Ray Tracing Theory And Realization In Mobile Communication Sysetm

Prediction of radio propagation plays a very important role in design and programming wireless communication network in modern mobile communication. With the fast development of digital mobile communication, and the best use of frequency spectrum, the size of urban cell is getting smaller, which is called microcellular. So the statistical comparability of different cell fades away and the previous empirical prediction model of radio propagation which based on a large amount of experimental data can not be used. Therefore a new accurate prediction model must be established to analyze the radio propagation in microcellular. Combining with physical optics(PO), geometry theory of diffraction(GTD) and uniform theory of diffraction(UTD), ray tracing can precisely and efficiently find the paths of rays, analyze multipath effect and calculate various channel parameters. Ray tracing is a method which fits for predicting the radio propagation in a microcellular. This paper provides an effective ray tracing method for prediction of microcellular radio propagation, which is called a ray tracing method based on virtual source binary tree. The algorithm uses a simple and effective binary tree to store the information of emission source, reflection source and diffraction source and can search the accurate ray paths from sending set to receiving machine in a complex scenario by traversing the binary tree. Besides, some accelerate methods are used in the algorithm to improve the efficiency of ray tracing. This algorithm is one kind of inverse algorithms, but it also contains the advantage of direct algorithms. It has the accuracy of inverse algorithms and the coverage area of direct algorithms. The algorithm is realized with VC++6.0 in this paper. This paper has counted the electric wave propagation path loss in a microcellular environment model and the results verify the validity of the ray tracing method.