This tool uses the forward and reverse power to calculate the **VSWR** (Voltage Standing Wave Ratio) and reflection coefficient (**Γ**). Both forward and reflected power are expressed in **Watt.**

## Formula

**Reverse Power _{%} = 100*(Reverse Power/(Reverse Power + Forward Power)**)

**Γ** = **√**(**Reverse Power _{%}/100)**

**VSWR = (1+|Γ|)/(1-|Γ|)**

## Example Calculations

If the forward power is **10 Watt**, and reverse power is **1 Watt**, this means that 10% of the power is reflected back to the source. In this case the **VSWR** is **1.92** and the reflection coefficient **Γ** is **0.32**.

If the transmit power is 25 Watt and 1 Watt is reflected back – this gives a **VSWR = 1.5**. Any value between 1.5 and 1 is a good value.

VSWR varies between **1** and **∞**.

**VSWR = 1** is ideal. In this scenario none of the input power is reflected back. **Reverse power = 0** and **Γ = 0**

**VSWR = ∞** is the worst condition. All of the power is reflected back. In this situation (refer to the equations above), **Γ** **= 1** and **VSWR = 2/0 = ∞**.

**Related Blog Posts and Calculators**

- How to improve VSWR – a simple technique to reduce mismatch
- VSWR to Reflected Power
- Impedance Mismatch Calculator
- VSWR from Forward and Reflected Power
- Return Loss to VSWR