The Smith chart
G. H. Bryant · Institution of Engineering and Technology eBooks · 1993
The Smith chart remains one of the most highly developed aids to microwave circuit design. In its common form it consists of loci of constant normalised resistance and reactance, plotted on a polar diagram representing the reflection coefficient at a fixed plane in a transmission system. A load reflection coefficient is related to voltages and/or currents measured at selected positions in an implicit transmission line; but in a microwave circuit, the perceived quantity flowing in the system is the power associated with an electromagnetic wave. The Smith chart is conveniently derived from traditional transmission line theory, with voltages and currents explicitly determined by the lumped or distributed circuit components.