Noise figure of broadband active metamaterials

Compared to passive metamaterials, active metamaterials made up of non-Fosters negative impedance converters (NICs) have been proposed with broadband and lossless negativeRe-μ (MNG) or μ-near-zero (MNZ) magnetic properties. However, the study of their noise performance still remains to be explored. Johnson noise will arise due to lossy conductors and nonlinear materials used for the design of the NICs. Based on the equivalent circuit model of the coupled elements, an analytical description is presented in this paper to predict noise performance of broadband active metamaterials based on NICs, and analyse its relation to effective constitutive material properties.