Telecom & Networking

Basic

Power Decibels

Ratio of two power levels expressed logarithmically.

Formula

dB = 10 \log_{10}\frac{P_1}{P_2}

Variables

dBDecibels

P_1Output power

P_2Reference power

Example

P1=100, P2=1: dB = 20

Did You Know?

Every 3 dB represents a doubling of power — a handy mental shortcut for engineers.

telecom decibel power

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