高精度法矢下切割面自适应的凸曲面射线寻迹  

Convex surface ray tracing based on adaptive cutting surface adjustment under exact normal vector

作　　者：李尧尧[1] 苏东林[1] 刘焱[1] 杨照[1] 

机构地区：[1]北京航空航天大学电子信息工程学院,北京100083

出　　处：《北京航空航天大学学报》2016年第12期2632-2639,共8页Journal of Beijing University of Aeronautics and Astronautics

基　　金：国家自然科学基金(61427803)~~

摘　　要：针对电大尺寸目标难以精确解析表达带来的一致性几何绕射算法应用难问题,提出了基于三角网格、适用于任意凸曲面的射线寻迹(TM-tracing)算法。应用工程中较易获取的三角网格及其协议,设计了一种满足快速多边搜索条件的网状数据存储链表;提出了满足寻迹要求的高精度法矢求解算法;采用切割面自适应调整的弧形拟合寻迹方法实现了爬行波寻迹算法;结合一致性几何绕射理论(UTD)实现了暗区场值求解算法。任意网格曲面射线寻迹结果表明:本文提出的寻迹算法适用于包括球、柱和锥在内的任意光滑凸曲面,寻迹偏差小于1.61%,寻迹速度为2.8 s,具有一定的工程应用价值。Electrical large targets are difficult to be accurately and analytically expressed and thus it is difficult to use uniform geometrical theory of diffraction （UTD） method for field computation. Aimed at this problem, a novel creeping ray triangular mesh tracing （TM-tracing） algorithm for arbitrary convex surface was proposed. Based on practical engineering triangular mesh and its protocol, a net-like triangular mesh data stor- age list which meets the rapid multilateral search criteria was designed. A high accuracy normal vector algo- rithm was proposed to satisfy the tracing requirement. Then a dynamic adjustment of the arc cutting surface fit- ting tracing method was proposed to realize creeping wave tracing algorithm. Finally, combined with UTD, shadow field value solving algorithm was realized. Aircraft-based ray tracing results show that TM-tracing algo- rithm can be applied to arbitrary smooth convex surfaces including sphere, cylinder and cone. Tracing speed is 2.8 seconds and deviation is less than 1.61%. It shows that the proposed algorithm has an application value in engineering.

关 键 词：三角网格 一致性几何绕射理论(UTD) 射线寻迹 短程线 爬行波 

分 类 号：TN011.4[电子电信—物理电子学] V219[航空宇航科学与技术—航空宇航推进理论与工程]