Power loss formula for impedance matching circuits dedicated to wireless power transfer

To design high efficiency WPT systems, we formulate the insertion loss in an L-shaped lumped-constant two-element matching circuit in terms of the elements´ quality factors and the input/output impedances which are complex impedances rather than mere resistances. The derived formula is explicit, and thus enables analytical design of high-efficiency matching circuits with a clear perspective. Some analysis examples by the formula are also given, which reveal interesting facts.