Loading artificial magnetic conductor and artificial magnetic conductor absorber with negative impedance convertor elements

The general properties of a frequency selective surface loaded with negative impedance converter (NIC)-based active loads are discussed from a theoretical perspective.The stability problem associated with NIC circuits embedded in artificial magnetic conductor (AMC) and AMC absorber applications is studied using pole-zero analysis. The requirements and constraints for achieving stable operation with enhanced bandwidth using negative capacitance as realized by a floating NIC network are derived. Furthermore, it is shown that it is nearly impossible to simultaneously implement a negative capacitor and a negative inductor to such structures. (C) 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:2111-2114, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27019