  We derive a lumped circuit model for inductive antenna spin-wave transducers
in the vicinity of a ferromagnetic medium. The model considers the antenna's
Ohmic resistance, its inductance, as well as the additional inductance due to
the excitation of ferromagnetic resonance or spin waves in the ferromagnetic
medium. As an example, the additional inductance is discussed for a wire
antenna on top of a ferromagnetic waveguide, a structure that is characteristic
for many magnonic devices and experiments. The model is used to assess the
scaling properties and the energy efficiency of inductive antennas. Issues
related to scaling antenna transducers to the nanoscale and possible solutions
are also addressed.
