Analysis of near-field power transfer using scattering parameters

Numerical analysis of the near-field power transfer for multi-user is performed by using the multi-port scattering parameters. The transfer power efficiency is derived by using the multi-port scattering parameters. Since the multi-port scattering parameters are easily measured by a vector network analyzer and calculated by a full-wave numerical analysis, it is convenient to investigate the relation between the power transfer efficiency and the geometry of the power transfer system such as relative positions between transmitting antennas and receiving antennas, antenna geometry, impedance matching of the antennas, and ohmic loss in antennas, which are important parameters to develop a near-field power transfer system with high power transfer efficiency.