Propagation of Electromagnetic wave radiated from rotating dipole antenna

First, the mathematical theorem about the rotation of polarization vector is presented. From this theorem it is shown that the circular-polarized electromagnetic wave satisfies the Helmholtz equation, but the linear-polarized one doesn´t satisfy it. It implies that the latter is not time-harmonic. The observed frequency of the circular-polarized wave radiated from a rotating dipole antenna is also evaluated.