R-FDTD与亚网格相结合技术及其应用

Reduced finite-difference time-domain method with subgridding and its application

提出了降维时域有限差分方法 (R FDTD)和亚网格相结合的技术 ,并应用于微带馈电缝隙天线的分析 .首先对微带馈电矩形缝隙天线阻抗特性和辐射特性进行了分析 ,所得数值结果与有关文献结果一致 .与常规的FDTD方法相比 ,明显地减少了内存需求和计算时间 .对工字形和燕尾形缝隙的微带馈电缝隙天线的输入阻抗和方向性图进行了分析计算 ,得到了工字型和燕尾型缝隙天线结构可以增宽频带、降低谐振频率等对工程设计有参考价值的结论 .数值结果表明 ,采用这种技术可以有效地处理包含细小结构的复杂对象的电磁问题 .

A novel approach of reduced finite-difference time-domain method (R-FDTD) combined with subgridding technique is proposed and applied to the analysis of microstrip-fed slot antennas. Firstly, the impedance and radiation characteristics of a microstrip-fed rectangular-slot antenna are analyzed and the obtained numerical results accord with those in literatures. Compared to normal FDTD method, memory requirement and CPU time are reduced obviously by the presented approach. Further more, the input impedance and radiation pattern of a microstrip-fed dumbbell-slot antenna and a microstrip-fed swallow-tailed-slot antenna are calculated. Some useful conclusions, such as the expansion of bandwidth and the reduction of resonant frequency by using swallow-tailed-slot antenna and dumbbell-slot antenna, are deduced for the engineering design. Numerical results show that it is feasible and numerically efficient to solve the electromagnetic problem of complex objects incorporating small features with the proposed approach.