If maximum and minimum voltages on a transmission line are 4 V and 2 V respectively, VSWR is

Concept:

• Voltage Standing Wave Ratio (VSWR) defines mismatch on the line.
• It is also the measure of the deviation of impedances or current or voltages from their central values.
•  \(VSWR=\frac{V_{max}}{V_{min}}\) -----(1)
• The value of VSWR varies from 1 to ∞.                  
•  (1 ≤ VSWR < ∞)

Calculation:

Given:

V_max = 4

V_min = 2

From equation (1):

\(VSWR=\frac{4}{2}\)

VSWR = 2

Important Points

Γ  is the amplitude ratio of reflected voltage to the forward voltage.

It also indicates a mismatch between the expected impedance and the actual impedance at that point.

\(Γ=\frac{Z_L-Z_0}{Z_L+Z_0}\)

Where,

Z_L = Load Resistance

Z₀ = Characteristic Impedance

The value of Γ varies between 0 and 1

0 ≤ Γ ≤ 1

Γ = 1 when there is complete reflection.