一种基于FDTD算法的局域导波端口激励

摘要

In order to figure out the distortion of radiation pattern, which is caused by backward leakage, second contamination and output boundary truncation, a novel Local Waveguide Port (LWP) technique based on FDTD technique is proposed in this paper. And the detail of boundary conditions and boundary parameters are given for the method. At the end of this paper, this LWP technique is utilized to analyze discontinuous rectangular waveguide, micro-strip antenna and slot antenna array excited by local waveguide port. The calculation results show that the high accuracy can be obtained in the discontinuous problem and the much better result can be achieved in the radiant problem. Consequently, this method can be used in both discontinuous problem and radiant problem.%　　为弥补传统导波端口在处理辐射问题的缺陷，解决导波端口后向泄漏和远场外推面截断而导致的辐射失真等问题。该文深入研究时域有限差分算法中导波端口激励的加载方式，首次提出了一种通用有效的局域导波端口，并对端口中各边界条件的参数配置和实现方法进行了深入论述。此外，利用该算法对不连续性波导、微带贴片天线和波导缝隙天线阵等实际问题进行了模拟仿真，结果表明，在处理波导不连续性问题时，该方法保持很高的计算精度；在处理导波端口的辐射问题时，传统方法存在较大误差，新方法则能取得很好的计算结果。因此该方法不仅适用于模拟导波端口激励的辐射问题，也适用于分析各类波导不连续性问题，具有普适性。