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CWNP Certified Wireless Network Administrator CWNA-109 · Domain 1: Radio frequency (RF) technologies

RF math: mW and dBm conversion, the rule of 10s and 3s, dB gain and loss, dBi vs dBd

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Last reviewed September 25, 2026 · Leer en español

Wireless professionals measure power in two ways: absolute power in milliwatts (mW) and relative or referenced power in decibels. The CWNA exam expects you to convert between them quickly, usually without a calculator. The good news is that a few simple rules cover almost every question.

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