151.  Radiation of Dipole Antenna

The radiation of Yagi-Uda antenna is the experimental evidence that the far-field radiation is mainly magnetic field.

The voltage distribution of a half-wavelength dipole antenna represents the fundamental resonance of standing wave. The electric field from the voltage distribution is given by Coulomb law. The magnetic field from the current distribution is given by Biot-Savart law. The electric field diminishes more than magnetic field over distance. The far-field radiation is dominated by magnetic field.

The radiation pattern of a half-wavelength dipole antenna is different from the intensity pattern of Poynting vector derived from the electromagnetic wave predicted by Maxwell'sequations which are mathematically incorrect due to singularity.