Dipole antenna pair revisited from kQ product and Poincare distance for wireless power transfer invited

摘要

As one of the basic structures for wireless power transfer, a symmetric dipole antenna pair is revisited in this paper. Since Friis formula is no longer applicable in the near-field region, we first employ kQ product as an alternative index of maximum power coupling efficiency. Then assuming optimum impedance matching circuits at both source and load ports simultaneously, we employ Poincare distance D as an associate index for the minimum power dissipation inside the matching circuits. Electromagnetic-field simulation is carried out to deduce the antenna's self and mutual impedances, which are converted into the above two indices. As a result, we find that the simple dipole antenna pair performs well (kQ > 1) as a wireless power coupler within the 0.2 wavelength range. Poincare distance is predicted as D 收起