dBm = dB relative to a reference power of 1 mW. This is often used to specify absolute power levels, e. To test your understanding, think about the questions. Optical loss is measured in “dB” which is a relative measurement, while absolute optical power is measured in “dBm,” which is dB relative to 1mw optical power Loss is a negative number (like –3. 2 dB) while power measurements can be either positive (greater than the reference) or negative (less than. To measure optical loss, you can use two units, namely, dBm and dB. Calculation Example: This calculator determines the received optical power (in dBm) by first converting the input power from milliwatts (mW) to dBm using the formula: P_in_dBm = 10 * log10. Unlike dB, dBm is an absolute unit of power.
[pdf] 