Understanding RF Power Units and Conversions

Introduction

This guide explains the different RF power units and how to convert between them.

Common RF Power Units

  • Watt (W):
    The standard unit of power, representing the rate at which energy is transferred.

  • dBm:
    A logarithmic unit of power relative to 1 milliwatt (mW).

  • dBW:
    A logarithmic unit of power relative to 1 watt (W).

RF Power Conversions

  • Watts to dBm:
    dBm = 10 * log10(Power in Watts * 1000)

  • dBm to Watts:
    Power in Watts = 10 ^ ((dBm - 30) / 10)

  • Watts to dBW:
    dBW = 10 * log10(Power in Watts)

  • dBW to Watts:
    Power in Watts = 10 ^ (dBW / 10)

Other Important Units

  • Power Density (W/m² and dBm/cm²):
    Measures the amount of power per unit area.

  • ERP (Effective Radiated Power):
    The amount of power that an antenna radiates.

  • EIRP (Effective Isotropic Radiated Power):
    The amount of power that an antenna would radiate if it were an isotropic antenna.

  • VSWR (Voltage Standing Wave Ratio):
    A measure of how well an antenna is matched to a transmission line.

  • Return Loss:
    A measure of the power reflected back from an antenna or load.

Understand RF power units and conversions with this guide!

Use RF & Electronics Power Conversion Tool