Enter your Forward Power and Reflected Power (with your choice of power units) to calculate your transmission line's VSWR, along with Return Loss, Reflection Coefficient, and Mismatch Loss — everything you need to evaluate how well your load is matched to your source.
VSWR
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Return Loss
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Reflection Coefficient
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Mismatch Loss
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VSWR (Voltage Standing Wave Ratio) measures how well impedances are matched in RF transmission systems. A perfect match is 1:1, while higher ratios indicate mismatches that can cause power loss and equipment damage.
VSWR 1.0:1 is perfect, 1.5:1 is good, 2.0:1 is acceptable for many applications, and 3.0:1 or higher indicates significant mismatch that should be addressed.
VSWR is calculated using the formula: VSWR = (1 + √(Pr/Pf)) / (1 - √(Pr/Pf)), where Pf is forward power and Pr is reflected power.
Return loss and VSWR are inversely related. Higher return loss (better) corresponds to lower VSWR (better). Return loss is expressed in dB and represents the ratio of reflected to incident power.
Yes, our calculator supports watts (W), milliwatts (mW), and dBm. You can select different units for forward and reflected power measurements.
High VSWR is caused by impedance mismatches between components, damaged cables, poor connections, incorrect antenna tuning, or using components with different characteristic impedances.
Reflection coefficient (Γ) is the ratio of reflected wave amplitude to incident wave amplitude. It ranges from 0 (perfect match) to 1 (total reflection) and is directly related to VSWR.
Mismatch loss represents the power lost due to impedance mismatch. Even small mismatches can result in measurable power loss, reducing system efficiency and potentially causing component heating.