Transmit power is the power of high-frequency transmitters.

• Transmitter output power is the power emitted at the RF output of a transmitter
• Radiated power or ERP (effective radiated power) is the radiated power in relation to a reference antenna, i.e. the antenna gain is included in the calculation here
• Transmitter input power is the power absorbed by the transmitter. The efficiency is calculated from the transmitter input power and transmitter output power.