基于ADI-FDTD的毫米波窄带正交模转换器设计

Design of Millimeter-wave Narrowband OMT Based on ADI-FDTD Method

由于传统分析正交模转换器(OMT)的模式匹配法和有限元法具有通用性不强、计算量大的局限性,因此基于单轴各向异性介质完全匹配层(UPML)理论,推导了三维情况下UPML交替方向隐式时域有限差分方法(ADI-FDTD)迭代公式,并将其推广应用于毫米波窄带OMT的分析。将分析方法的计算结果与FDTD和HFSS结果进行对比,在同等计算精度情况下,存储量与FDTD相当,但大大小于HFSS,计算速度比FDTD提高了近5倍,比HFSS提高了近10倍。

An unsplit-field perfectly matched layer medium based on Gedney＇s uniaxial PML（UPML） scheme was proposed for an unconditionally stable three-dimensional alternating direction implicit finite-difference time- domian （ADI-FDTD）method. The method is extended to the design of a mm-wave narrowband OMT. The numerical results are in good agreement with the result obtained by conventional FDTD method and HFSS while the required computational memory is correspond to the FDTD method and a quarter of HFSS; the computing time is five times less than FDTD and ten times less than HFSS.