22. Transmission lines
For a plane wave in an unbounded medium, because of the wave had neither electric nor magnetic field
components in the longitudinal direction, it can be referred as a transverse electromagnetic wave.
Let us consider those waves that can exist in regions bounded by conductors. These waves can be
referred as guided waves.
There are three types of guided waves: the transverse electromagnetic wave, the transverse electric
wave, and the transverse magnetic wave.
Guided waves require conductors for their existence and propagate along the length of the conductors.
When the magnetic field of a guided wave has a component in the direction of its propagation in
addition to its other components in the transverse direction, and the electric field is entirely in the
transverse direction, the guided wave is called a transverse electric (TE) wave.
23. Transmission lines
The guided wave is referred to as a transverse magnetic (TM) wave when the magnetic field is entirely
in the transverse direction and the electric field has a component in its direction of propagation.
TE and TM waves can exist within a single hollow conductor, Waveguides and cavity resonators.
The transverse electromagnetic (TEM) wave, also known as the principal wave (or principal mode),
requires two or more conductors for its existence.
The wave propagates along the length of the conductors with its electric and magnetic fields entirely
transverse to its direction of propagation. Neither the electric field nor the magnetic field has a
component in the direction of propagation of the wave. Such a wave, very similar to a plane wave, can
be excited at any frequency and is used to transmit signals along transmission lines.
24. Transmission lines
Among the endless varieties of transmission lines are parallel-wire lines, coaxial lines, and
microstrip
The properties of the dielectric medium are assumed to be the same throughout the length of the
transmission line.
Also, each conductor of the transmission line is made of the same material, has the same
dimensions, and has the same cross-sectional area along the length of the line.
A transmission line satisfying these criteria is usually referred to as a uniform transmission line.
A useful graphical technique to analyze a transmission line is referred to as a Smith chart
32. Parameters of a parallel-plate transmission line
Capacitance of a parallel-plate transmission line
33. Parameters of a parallel-plate transmission line
Capacitance of a parallel-plate transmission line
34. Parameters of a parallel-plate transmission line
Capacitance of a parallel-plate transmission line
35. Parameters of a parallel-plate transmission line
Capacitance of a parallel-plate transmission line Inductance of a parallel-plate transmission line
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