Return Loss to VSWR Converter

dB

This converter allows you to transform the return loss of an RF device, expressed in dB, into VSWR (Voltage Standing Wave Ratio). VSWR is a key indicator of the impedance match between a transmission line and its load, and reflects the quality of signal transmission.

Formula

Γ = 10^(-RL / 20)

VSWR = (1 + Γ) / (1 – Γ)

Explanation of the formula

The first equation calculates the reflection coefficient Γ from the return loss RL. It converts the value in dB into a linear coefficient between 0 and 1.

The second equation converts this reflection coefficient to VSWR, which gives a direct measure of the impedance mismatch on the line. A VSWR close to 1 indicates almost perfect matching, while a high VSWR signals significant signal losses due to reflections.

Uses

  • Evaluate the quality of impedance matching in RF and antenna systems.
  • Determine the efficiency of a transmission line or connector.
  • Optimize coupling between components to reduce losses and reflections.
  • Facilitate the design and diagnosis of communications and radar systems.