In a radio communication system, what does 'dBm' measure?

The term 'dBm' specifically refers to the measurement of power level in decibels (dB) when that power level is referenced to one milliwatt (mW). This unit is a common way to express small power levels and is frequently used in radio communications to quantify signal strength. For example, if a signal has a power level of 0 dBm, it corresponds to exactly 1 milliwatt of power. If the signal were at +10 dBm, it would indicate a power level of 10 milliwatts.

Understanding this terminology is critical in the field of radio communication, as it helps professionals gauge the performance and reliability of various systems and components. While voltage levels, frequency ranges, and audio quality are also important aspects of radio communication, they are not measured in dBm. Instead, those aspects utilize different metrics and units, thus highlighting the importance of knowing what dBm specifically measures in the context of power levels.