Voltage Standing Wave Ratio

Engineering & Applied Technologies Dictionary
Voltage Standing Wave Ratio (VSWR) is a dimensionless measure of the amplitude ratio between maximum and minimum voltage along a transmission line caused by reflections; for line-referenced magnitude VSWR = (1+|Γ|)/(1-|Γ|), where |Γ| is the magnitude of the voltage reflection coefficient. VSWR = 1 indicates a perfect match.