Energy Transport Velocity for Hertzian Dipole

Actually there is great interest to understand radiation mechanism of antennas. Obviously, any analysis has to include energy and power related to those phenomena. Energy is very important in order to know how the antenna works; in particular, energy velocity allows us to study the behavior of dipole. In this article we calculate the total instantaneous energy velocity in function of radial distance, in the near and far zones, for a Hertzian dipole with harmonic excitation. That energy has two components, one in the radial direction and the other in thetas direction. Only the radial component contributes to average transport velocity of energy. Theoretical results show energy movement is an accelerated one, once the speed of light is reached a negative acceleration appears, then the velocity goes to zero, and begins another cycle in which positive acceleration appears

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