Effective Permeability Retrieval of Near-field Metamaterial based on Equivalent-Circuit Model

In general, S-parameter methods have been used to calculate electromagnetic parameters of artificially structured materials, which is limited to far-field region. In reality, it is found that such method is not well suited for near-field application, such as wireless power transfer (WPT). In this paper, we present an equivalent-circuit model for extracting relative permeability of near-field metamaterial (NFM). Based on the proposed circuit model, it is possible to analyze the magnetic properties of NFM, and the resonant frequency can be quickly predicted. Finally, full-wave simulation and experimental measurement verify the analysis result.