Antenna radiation in a moving dispersive medium

The general problem of calculating the radiation field of an antenna immersed in a moving dispersive medium is formulated as an algebraic equation in wave-vector frequency space for the potential 4-vector in the rest frame of the antenna, and is solved in terms of a Green´s function having the form of a one-dimensional integral. The special case where the moving medium is a homogeneous ionized gas (plasma) and the antenna is an oscillating dipole is studied in detail. It is found that the far-zone field is not transverse and the Poynting vector is not purely radial.