论文标题
通过Rational Krylov拟合减少分层波导的模型顺序降低
Model order reduction of layered waveguides via rational Krylov fitting
论文作者
论文摘要
最近，有理近似是用于外波传播问题解决方案的有效数值工具。当前，该技术仅限于沿主要传播方向不变的波介质。我们提出了一种新的基于模型订单的方法，用于压缩具有分层夹杂物的无界波导。它基于使用RKFIT方法的非线性最小二乘问题的解决方案。我们表明，可以将近似值转换为有效的Krylov框架内的准确有限差异表示。数值实验表明，与以前的分析方法相比，RKFIT计算更准确的网格，甚至在存在明显的散射共振的情况下起作用。光谱适应效应允许有限的差异网格，其尺寸接近甚至低于Nyquist极限。
Rational approximation recently emerged as an efficient numerical tool for the solution of exterior wave propagation problems. Currently, this technique is limited to wave media which are invariant along the main propagation direction. We propose a new model order reduction-based approach for compressing unbounded waveguides with layered inclusions. It is based on the solution of a nonlinear rational least squares problem using the RKFIT method. We show that approximants can be converted into an accurate finite difference representation within a rational Krylov framework. Numerical experiments indicate that RKFIT computes more accurate grids than previous analytic approaches and even works in the presence of pronounced scattering resonances. Spectral adaptation effects allow for finite difference grids with dimensions near or even below the Nyquist limit.
