Transverse electromagnetic (TEM) modes have . they cannot propagate through a single conductor. TEM modes are dispersionless, with z-component of wavenumber given by
where is the angular frequency and c is the speed of light. ransverse electric (TE) modes have and . TE modes transmit frequencies larger than a characteristic cutoff frequency with dispersion. For a rectangular waveguide,
(1)
(2)
(3)
Transverse magnetic (TM) modes have , . TM modes transmit frequencies larger than a characteristic cutoff frequency with dispersion. For a rectangular waveguide,
(4)
(5)
(6)
For TE and TM modes, the following quantities are defined
. they cannot propagate through a single conductor. TEM modes are dispersionless, with z-component of wavenumber given by 
is the angular frequency and c is the speed of light.
and 
. TE modes transmit frequencies larger than a characteristic cutoff frequency with dispersion. For a rectangular waveguide,
,
. TM modes transmit frequencies larger than a characteristic cutoff frequency with dispersion. For a rectangular waveguide,
