Return Loss Calculator





Formula

To calculate the return loss:

\[ RL = -20 \times \log_{10} \left( \frac{P_r}{P_i} \right) \]

What is a Return Loss?

Return loss is a measure of how well a device or system reflects power in a signal back to its source, often used in telecommunications. It is expressed in decibels (dB) and indicates the ratio of power arriving at a device to the power reflected back. A higher return loss value indicates a lower amount of reflection, meaning the system or device is better at transmitting power efficiently. This is desirable as it reduces signal distortion and improves overall system performance.

Example Calculation 1

Let's assume the following values:

Step 1: Divide the reflected power by the incident power:

\[ \frac{P_r}{P_i} = \frac{0.5}{10} = 0.05 \]

Step 2: Take the base 10 logarithm of the quotient:

\[ \log_{10}(0.05) = -1.3010 \]

Step 3: Multiply the result by -20:

\[ RL = -20 \times (-1.3010) = 26.02 \text{ dB} \]

Example Calculation 2

Let's assume the following values:

Step 1: Divide the reflected power by the incident power:

\[ \frac{P_r}{P_i} = \frac{2}{50} = 0.04 \]

Step 2: Take the base 10 logarithm of the quotient:

\[ \log_{10}(0.04) = -1.3979 \]

Step 3: Multiply the result by -20:

\[ RL = -20 \times (-1.3979) = 27.96 \text{ dB} \]