VSWR Measurements

The ratio of the maximum to minimum value of the voltage amplitude on a lead is known as the VSWR value.The quotient is a measurement of the quality of the adaptation or of the fluctuation of the resulting voltage surge.In the case of a mismatch,the outward wave is reflected onto the contact point.By superimposing the outward and return waves,a greater difference is obtained between the maximum and minimum voltage than for the outward wave.The VSWR value is 1.0 for a perfect adaptation.The reciprocal value is known as the adaptation factor  m.

r.      reflection factor

m.    Adaptation factor

a.    Return Loss

VSWR    Voltage standing wave ratio