Different implementations of material independent multi‐order nearly perfectly matched layers for EM simulations. Issue 11 (1st July 2020)

• Record Type: Journal Article
• Authors: Wu, Peiyu; Xie, Yongjun; Jiang, Haolin; Niu, Liqiang
• Is Part Of: Microwave and optical technology letters. Volume 62:Issue 11(2020:Nov.)
• Page Start: 3485
• Page End: 3498
• Publication Date: 2020-07-01
• Subjects: bilinear Z‐transform -- direct Z‐transform -- finite‐difference time‐domain -- matched Z‐transform -- multi‐order -- nearly perfectly matched layer; Microwaves -- Periodicals; Optics -- Periodicals; 621
• DOI: 10.1002/mop.32495
• Languages: English
• ISSNs: 0895-2477

Abstract

Abstract: To deal with EM simulations with the low‐frequency evanescent and propagation waves, multi‐order nearly perfectly matched layers (NPML) with complex frequency shifted factor are presented to terminate finite‐difference time‐domain (FDTD) domains. By incorporating the digital signal processing techniques including the bilinear Z‐transform, matched Z‐transform, and direct Z‐transform methods, the proposals can not only obtain better performance compared with the original NPMLs but also have considerable efficiency compared with other multi‐order PMLs. Meanwhile, these implementations can terminate arbitrary mediums without changing the field‐updated equations in the PML regions. Based upon the multi‐order concept, the proposals can be switched flexibly between the first order and multi‐order according to different EM simulations by changing the optimized parameters. Numerical results indicate that our proposals can not only enjoy higher computational efficiency but also easier to implement according to different mediums in the EM modeling and simulations.