三维城市环境下射线追踪加速算法

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针对传统的射线追踪算法在三维城市环境下存在海量计算、效率低下的问题,该文提出基于城市布局分区、降维、朝向测试、加速多镜法相结合的射线追踪算法。针对各个城市不同的布局特点对地理空间进行区域划分,构建空间索引,排除大量与射线追踪无关的城市建构筑物;同时采用降维处理、朝向测试、加速多镜像相结合的方式,减少空间几何计算的次数,从而提高计算的效率。将该算法与信号覆盖预测理论相结合,实现了点对点的信号准确计算。基于城市移动多媒体的预测结果表明:该算法可以准确、快速地实现城市的区域场强计算。 In order to solve the problem of mass ray tracing and inefficiency of traditional ray tracing algorithm in 3D urban environment, this paper proposes a ray tracing algorithm based on urban layout partition, dimension reduction, heading test and accelerated multi-mirror method. According to the different layout characteristics of each city, the paper divides the geographical space, constructs the spatial index and excludes a large number of urban constructions unrelated to the ray tracing. At the same time, it uses the combination of dimension reduction processing, orientation test and accelerated multi-mirror to reduce the spatial geometry calculation The number of times, thereby enhancing the efficiency of the calculation. The algorithm is combined with the theory of signal coverage prediction to realize the accurate calculation of point-to-point signal. The prediction results based on urban mobile multimedia show that the algorithm can accurately and quickly calculate the urban area strength.
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