In radar, the amount of power received at the antenna after being scattered by a target. This power is normally on the order of microwatts as compared with the kilowatts or megawatts of transmitted power. By convention, received power is measured in decibels relative to a reference value of 1 mW, that is, in dBm. The average received power is proportional to the radar reflectivity of the target, while fluctuations in the received power are caused by relative motions among the individual scattering elements that make up the target.