  We perform measurements of the radiation pressure of a radio-frequency (RF)
electromagnetic field which may lead to a new SI-traceable power calibration.
There are several groups around the world investigating methods to perform more
direct SI traceable measurement of RF power (where RF is defined to range from
100s of MHz to THz). A measurement of radiation pressure offers the possibility
for a power measure traceable to the kilogram and to Planck's constant through
the redefined SI. Towards this goal, we demonstrate the ability to measure the
radiation pressure/force carried in a field at 15~GHz.
