采用滑动窗时域有限差分法对不规则地形电波传播预测  

Predicting radiowave propagation over irregular terrain based on moving window finite-difference time-domain methods

作　　者：赵守俊[1] 王志慧[2] 王华力[1] 白冬林[3] 

机构地区：[1]解放军理工大学通信工程学院,江苏南京210007 [2]江南计算技术研究所,江苏无锡214083 [3]西安通信学院,陕西西安710106

出　　处：《解放军理工大学学报（自然科学版）》2008年第1期11-14,共4页Journal of PLA University of Science and Technology(Natural Science Edition)

基　　金：国家自然科学基金资助项目(60572095)

摘　　要：为了解决大区域电波传播精确预测时计算量大的问题,采用滑动窗时域有限差分方法对不规则地形上短波频段的地波传播进行预测。将经典FDTD(finite-difference time-domain)与脉冲追踪相结合,采用UPML吸收边界处理有耗地形,使垂直于地面的二维FDTD计算区域随脉冲传播而滑动,在迭代过程中保存必要的场分量,处理后得到不规则地形上的路径损耗与传播路径的关系曲线,并与经典的几何绕射理论的计算结果进行了比较。结果表明,其优点在于保持FDTD全波时域分析准确性高的特点同时降低了计算量。讨论了计算区域在滑动过程中由于包含的后向波信息的局部性对计算结果的影响,以及顶部吸收边界对侧向波的反射带来的误差。数值仿真结果表明了此方法的有效性。In order to model ground wave propagation accurately,MWFDTD（moving window finite-difference time-domain） was applied to predicting the path loss of ground wave over irregular terrain.This is a hybrid approach from FDTD and tracing pulse.UPML ABC was used to deal with lossy terrain.Two-dimension FDTD calculation region moves with propagation pulse.Necessary field intensity was saved and the path loss was obtained.The result obtained by MWFDTD was compared with the result obtained by UTD.This method not only contains characteristics of FDTD but also reduces the time of running FDTD program.Finally,the accuracy of MWFDTD affected by reflection wave from ABC and the error caused by the local moving window were discussed.The simulation result shows that this approach is efficient.

关 键 词：滑动窗时域有限差分法 不规则地形 地波 路径损耗 

分 类 号：TN820[电子电信—信息与通信工程]