Incident wave VI(t) propagates from the left to the right side of the screen and it is described by the following eqaution :
Reflected Wave VR(t) propagates from left to right when the load is not matched to the propagation medium. The equation of VR(t) is :
The summation of both waves produces a stationary wave inside the propagation medium as it is show in the third figure in black.
Characteristics of the stationary wave
The maxima of the stationary wave occurs when the incident wave VI(t) is in phase with the reflected wave VR(t), the maximum is : Emax = VI,max
+ VR,max. The minima of the wave occurs when the reflected wave VR(t) is 1800 of of phase with VI(t) : Emin = VI,max - VR,max
Voltage Standing Wave Ratio.
parameter used to quantify the presence of the standing wave in the propagation medium. The eqaution used to describe the VSWR is given by :
The distance between two consecutive peaks of the SW is given by the following expression :
With λ the wavelength of the incident or the reflected wave.