The Research On Radio Propagation Prediction Accelerate Model Of Three-dimensional Urban Environment

The mobile network planning is important in the applications of3D city. According to theforecast results to optimize the radio network base station, which is of great significance toenhance the vitality of the construction of digital cities. Ray tracing techniques have beenused extensively for the modeling of the propagation characteristics in small cells. However,the model is very time-consuming due to a large number of rays and tests, which impacts onits engineering application. The efficiency and accurate three-dimensional ray tracing methodhas been the hot spots of domestic and international academic research.In this paper, an efficient ray tracing algorithm, which is called unified virtual source raytracing, is proposed. The algorithm can quickly retrieve the ray propagation path by usingdatabase search technology and the accuracy of calculation is also very considerable and thealgorithm can be applied to urban3D environments with arbitrary building layouts andheights. The main findings in this paper are:1) Improving the ray-tracing technique, this is based on image theory, with highcomputational efficiency by using database search technology. Unlike the conventional imagemethod, this method has two steps: direct search and reverse search. Virtual source tree iscreated by directing search, after creating the virtual source tree, by inversing search, it canfind all valid ray-tracing paths from transmitter to receiver.2) Designing the ray tracing database, the efficient data storage, search technologythroughout the entire calculation process to achieve the speed of the ray-tracing.3) Based on the imaging theory and the framework of.NET Remoting, the idea ofparallel ray tracing model is proposed. It calls and starts the remote computing object, andassigns masks dynamically through computing the completion description with the sub-tree ofsecondary visual source.4) Studying the method of district field strength coverage prediction and ray-tracingmodel is applied to the residential field strength coverage prediction.