一种改进的Mur吸收边界条件

An Improved Mur Absorbing Boundary Condition

吸收边界条件是时域有限差分(FDTD)算法解决电磁问题的重要条件。提出一种改进的吸收边界条件。将惠更斯面推广到二维的时域有限差分算法中,并利用惠更斯面来改进Mur吸收边界。惠更斯面具有理论基础成熟、编程简单、占用的计算内存少等优点,可以方便地插入到FDTD计算域中。FDTD数值仿真证明,惠更斯面在增加少量计算量的同时大幅度提高了Mur边界的吸收性能。而在应用的截断边界元胞数目相同的情况下,改进的Mur吸收边界能达到比PML吸收边界更好的吸收效果。

Absorbing boundary condition is an important condition for solving electromagnetic problems by finite difference time domain （FDTD） algorithm. An improved absorbing boundary condition is proposed. The Huygens surface is ex- tended to the two-dimensional finite difference time domain algorithm, and then used to improve Mur absorbing boundary. Huygens surface takes the advantages of a mature theoretical basis, simple programming and less computational memory. It can be easily inserted into the FDTD calculation domain. FDTD numerical simulation verifies that Huygens surface greatly improves the Mur absorbing performance with increasing a small amount of calculation. Compared with the PML absorbing boundary, the improved Mur absorbing boundary can reach a better absorption effect when the numbers of truncated boundary cells of both are same.