Analyses of propagation characteristics by VRML models along railway

Abstract

In this paper, we show simulation results on radio propagation characteristics of a train radio system using 3D VRML (virtual reality modeling language) models along railway tracks. Conventionally, we have studied the modeling technique by scanning actual environments along the railway. In this technique, we are able to obtain 3D coordinates of points along railway environments by installing laser scanners and line cameras on a train. Next, 3D coordinates are converted into polygon models, and in addition, camera images are pasted. Finally, the models which contain shapes of wayside structures and landforms are created. These models are available for calculating radio propagation characteristics. This modeling technique contributes to reducing the burden of radio measurements, and to design wireless systems precisely. Here, we show some calculated examples on received levels of a train radio system based on polygon models, compared with experimental results.