준 3차원 환경에서의 광선 추적 기법 가속화를 위한 전처리 기법

Ray tracing method has been widely used to predict propagation characteristics of urban environments. For large and complex environments, however, ray tracing method consumes huge computation time. In this paper, we propose a pre-processing method, Relative Position Measures (RPM), to accelerate ray tracing method for quasi three-dimensional environments. The conventional Prior Distance Measures (PDM) can reduce the number of ray-facet intersection tests. However, PDM reduces the number of tests for multiple reflections only and the efficiency of PDM fluctuates dramatically as the environments change. By combining the conventional PDM with an angular division concept, RPM can reduce the number of intersection tests for both single and multiple reflections efficiently and is more robust to various propagation environments that PDM.