Subcell Lumped Element Modeling in Mrtd with Applications to Metamaterial Characterization

Methods to model metamaterial structures consisting of lumped elements embedded into transmission lines using multiresolution time-domain (MRTD) are presented in this paper. Specifically, this paper presents the modeling of lumped elements in MRTD, including elements that are smaller than a cell (subcell modeling). Using this technique, several lumped elements in any configuration can be modeled within a cell. The technique presented here is based on a deconstruction/reconstruction algorithm originally developed for subcell PEC modeling, and is here extended to lumped elements. MRTD is particularly well suited to metamaterial modeling due to its adaptive gridding. In addition, as a time domain method, properties such as negative group delay can be observed directly in the time domain response.