A simple series LC circuit can generate electromagnetic (EM) waves at its resonant frequency, with the wavelength determined by the circuit's physical size and component properties. The electric (E) and magnetic (B) fields of the EM wave are in phase as they propagate, despite the energy in the capacitor and inductor being 180 degrees out of phase in the circuit. The current in the circuit, particularly in the inductor, is responsible for generating the magnetic field, while the electric field is created by the acceleration of electrons. Antennas are designed to optimize the radiation of these waves, and the radiation process involves the movement of electrons, which creates a radiation resistance that affects efficiency. Understanding the relationship between circuit components and EM wave propagation is complex, particularly regarding the phase relationships in the near and far fields.
