What Is VOLTAGE STANDING WAVE RATIO – Telecom?
SWR is the ratio of maximum voltage along a transmission line to the minimum voltage or ratio of maximum current to the minimum current. SWR = V(max)/V(min) = I(max)/I(min) It is an index of many properties of a mismatched line and a convenient quantity in making calculations in line performance. The greater the mismatch the greater the ratio of maximum voltage to minimum voltage. If the source and load impedance are known than SWR = R(load)/R(source) or visa versa. The larger value is used in the numerator so that SWR>1. If the load contains no reactance than SWR = R/Zo where, R is the resistance of the load and Zo is the characteristic impedance of the line. Or when R
