Mode-Based Estimation of 3 dB Bandwidth for Near-Field Communication Systems

A new method for estimating the 3 dB bandwidth of near-field communication (NFC) systems using identical electrically small antennas is proposed. The method is based on equivalent circuit representation using the addition theorem, an approach used in the analysis of coupled antennas, and the correction factor derived from antenna impedance characteristics. In addition, variation in the 3 dB bandwidth with respect to the relative position and orientation of the NFC system is investigated using the proposed method.