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dB / decibel

Decibels express a ratio logarithmically. For power, use 10 · log₁₀(P₂/P₁), allowing gains and losses in a chain to be added.

Also found under: Dezibel · Decibel · dB

A concrete example

+3.01 dB is approximately double the power; −10 dB is one tenth.

What to keep in mind

The familiar 20-log voltage conversion represents a power ratio only when impedances are equal.

Further reference

Original explanation based on the technical documentation. Reviewed on 15 October 2026.

Analog Devices · Measurement and Control of RF Power ↗