A PML using a convolutional curl operator and a numerical reflection coefficient for general linear media

A general time domain representation of the Chew and Weedon [1994] stretched coordinate perfectly matched layer (PML) absorbing boundary condition is described. This new approach mathematically operates on the spatial field derivatives and allows the PML update equations to be trivially derived from any set of general linear medium update equations. A method for calculating the frequency dependent reflection coefficient for this form of the PML is derived for general linear media. Two and three dimensional numerical test results, which validate the calculation of the reflection coefficient, are presented. The range of numerical tests include the PML matching of free space, a magnetoplasma, and a free space waveguide. Improving the reflection coefficient is examined.