Leitungstheorie
Transmission line cables require impedance matching to carry electromagnetic signals with minimal reflections and power losses. The distinguishing feature of most transmission line cables is that they have uniform cross sectional dimensions along their length, giving them a uniform electrical characteristic impedance. Signal terminators are designed to specifically match the characteristic impedances at both cable ends. For many systems, the terminator is a resistor, with a value chosen to match the characteristic impedance of the transmission line, and chosen to have acceptably low parasitic inductance and capacitance at the frequencies relevant to the system. Examples include 75-ohm resistors often used to terminate 75-ohm video transmission coaxial cables.