Characterization and Measurement of Passive and Active Metamaterial Devices

摘要

This document addresses two major obstacles facing metamaterial development: uncertainty in the characterization of electromagnetic field behavior in metamaterial structures and the relatively small operational bandwidth of metamaterial structures. To address the first obstacle, a new method to characterize electromagnetic field behavior in a metamaterial is presented. This new method is a bistatic radar cross section (RCS) measurement technique. RCS measurements are well-suited to measuring bulk metamaterial samples because they show frequency dependence of scattering angles and offer common postprocessing techniques that can be useful for visualizing results. To address the second obstacle, this document characterizes the effectiveness of an adaptive metamaterial design that incorporates a microelectromechanical systems (MEMS) variable capacitor. Applying voltages to the MEMS device changes the resonant frequency of the metamaterial. In this research, computational models show that the size of the adaptive metamaterial unit cell should be increased to improve the responsiveness of the resonant frequency to changes in the MEMS capacitor.