【摘 要】
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The space partitioning algorithm based on the round-ing and addressing operations has been proved to be an effi-cient space partitioning algorithm with the potential for real-time calculation. An improvement on this kind of space partitioning al-gorithms
【机 构】
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School of Aeronautic Science and Engineering, Beihang University, Beijing 100191, China;Key Laborato
论文部分内容阅读
The space partitioning algorithm based on the round-ing and addressing operations has been proved to be an effi-cient space partitioning algorithm with the potential for real-time calculation. An improvement on this kind of space partitioning al-gorithms for solving complex 3D models is presented. Numerical examples show that the efficiency of the improved algorithm is better than that of the original method. When the size of most target elements is smaller than the size of spatial grids, the effi-ciency of the improved method can be more than four times of that of the original method. An adaptive method of space parti-tioning based on the improved algorithm is developed by taking the surface element density or the curvature as the threshold for deep partitioning and conducting the deep partitioning using the octree method. A computer program implementation for apply-ing the method in some typical applications is discussed, and the performance in terms of the efficiency, reliability, and re-source use is evaluated. Application testing shows that the re-sults of the adaptive spacing partitioning are more convenient for the follow-up use than that of the basic uniform space partitioning. Furthermore, when it is used to calculate the electromagnetic scattering of complex targets by the ray tracing (RT) method, the adaptive space partitioning algorithm can re-duce the calculation time of the RT process by more than 40％compared with the uniform space segmentation algorithm.
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