VSWR（Voltage Standing Wave Ratio）

This is the voltage standing wave ratio, and is a parameter that indicates the relationship between the traveling wave and the reflected wave. It is essentially the same as Return Loss and can be converted using a fixed formula (see Return Loss section).
VSWR is defined as (1+reflectance)/(1-reflectance) and is 1.0 if there is no reflection (reflectance is an absolute value).