Five modes of propagation of electromagnetic waves

Electromagnetic waves are propagated in five different modes. They are transverse electric magnetic (TEM) mode, transverse electric (TE) mode, transverse magnetic ™ mode, hybrid EH mode and hybrid HE mode. When the propagation of electromagnetic wave through free space or through a transmission line is in coaxial format or in parallel wire format, the mode of propagation is TEM. Here the electric and magnetic fields associated with the wave lie in the plane perpendicular to the direction of propagation and the magnetic and electric fields are at right angles to each other. TE and TM mode propagation transpires when an electromagnetic wave is confined within a metallic waveguide. The shape of the waveguide can be rectangular or cylindrical. In TE mode, electric field vector lies entirely in transverse plane at right angles to the direction of propagation. In TM mode, magnetic field vector lies entirely in transverse plane at right angles to the direction of propagation. In hybrid modes, both electric field vector E and magnetic field vector H have finite components along the direction of propagation.