The VSWR calculator helps determine the quality of impedance matching in an RF system.
It provides key information on reflection coefficient, return loss and mismatch loss.
Formula used
Γ = (VSWR – 1) / (VSWR + 1)
RL = -20 × log₁₀(Γ)
ML = -10 × log₁₀(1 – Γ²)
Explanation
Γ represents the reflection coefficient, indicating the proportion of signal reflected by a mismatched impedance.
RL (Return Loss) shows the power lost by reflection in decibels, while ML (Mismatch Loss) shows the total loss due to mismatch.
A VSWR of 1 corresponds to a perfectly matched system, where Γ = 0, RL and ML are infinite.
Calculation example
For VSWR = 1.5 :
Γ = (1.5 – 1) / (1.5 + 1) ≈ 0.2
RL = -20 × log₁₀(0.2) ≈ 13.98 dB
ML = -10 × log₁₀(1 – 0.2²) ≈ 0.18 dB
Benefits and Use
- Allows you to quickly check the impedance matching of an RF line.
- Facilitates the reduction of reflection losses in transmission systems.
- Useful for RF engineers, technicians and antenna designers.
- Helps optimize the overall performance of communication and transmission systems.
