Research Of Ray-Tracing Algorithm For The Micro-Cell Of Mobile Communication System

Accompanying with the realization of the 3rd-generation technology, propagation properties of micro-cell wireless mobile channel is very important in the research and development of wireless transmission technique including the design, programming and optimization of wireless communication net. In recent years, the field strength is estimated using the ray-tracing method based on the Image-Theory, Geometrical Theory of Diffraction and Uniform Geometrical Theory of Diffraction, and is used on estimation for wireless channel. The efficiency and reliability are always the most important factors for the algorithm of the ray-tracing. A new approach of ray-tracing method based on a mirror-tree of son-brothers is presented in this paper. The mirror-tree is used to store the data of transmitting source, reflection source, diffraction source and receiving points. Using the mirror-tree of son-brothers, the order of reflection and diffraction can be changed. The actual antenna pattern is integrated with the ray-tracing method in this paper. The calculation efficiency of ray-tracing method is enhanced using the corresponding directivity function of antennas. The path search and the calculation of the path fading can be completed using the ray-tracing software realized with VC++6.0. Many acceleration algorithms is used such as back-collection, the base display-area, etc. The results calculated by the ray-tracing software is compared with the measured ones, and the reliability of the algorithm is proved.