Gis-based Radio Wave Propagation Prediction System

The series works in wireless network coverage are very complicated, which contains station layout, location selection, field density forecasting, coverage analysis, interfence analysis, frequency allocation and so on. While the traditional method of the wireless network coverage which operates on the maps manually is lack of precision and flexibility. Especially in the area of complicated terrain, accurate information of the station is needed to get the correct results in the interfence analysis and coverage calculation. With the development of computer, mathematic and geography technologies, the propagation forecasting system which is based on geography information system (GIS) has expressed its huge advantages and potential in communication system design and electromagnetism radiation analysis.The author's works are below:1. The basic theories of propagation are introduced. The diffraction propagation model and the calculation flow based on these theories are researched which are suitable for realizing with computers.2. The GIS technology which is related to the propagation forecasting is studied. The terrain analysis technologies of the GIS are used to analyze the propagating path, and the diffraction propagation arithmetic is realized which have considered the affection of the terrain. Based on the visual technology of the space data of the GIS, the visual method of the propagation forecasting is researched.3. Following the work above, more efforts have been paid on the realization and application of the diffraction propagation model. The application interface of the GIS and the station simulation database are also constructed, the calculation function and calculation flow of the diffraction model are detailed and fulfilled. The application examples of the propagation forecasting system are summarized and verified at last.Utilizing the propagation model which is based on the 3-D GIS, the electric wave propagation forecasting system can forecast the field density distribution in complex terrain area and realize the best spectrum allocation. Using this system, the wireless network designer can achieve the best signal coverage and more system capacity with limited spectrum resource.