
3 Transmission lines
3.1 General considerations
The purpose of any transmission line is to transfer power between a
source and a load with the minimum of loss and distortion in either
amplitude, frequency or phase angle.
Electrons travel more slowly in conductors than they do in free
space and all transmission lines contain distributed components: re-
sistance, inductance and capacitance. Consequently, lines possess an
impedance which varies with frequency, and loss and distortion occur.
Because the impedance is not constant over a wide frequency band the
insertion loss will not be the same for all frequencies and frequency
distortion will arise. A wavefront ...