voltage standing-wave ratio
- For a given transmission line, such as a coaxial cable or waveguide, the ratio of the maximum voltage to the minimum voltage. It is a measure of the impedance matching of the line. This ratio is equal to 1 when there is complete impedance matching, in which case the maximum possible RF power that reaches the load, such as an antenna. Its abbreviation is VSWR. Also called standing wave ratio (1).