Which component radiates energy into space?

• A. Antenna
• B. Transmitter
• C. Transmission Line
• D. Receiver

Answer: (A)

The energy is radiated into space by the antenna. When the transmitter’s RF power is fed to the antenna, the current distribution on the antenna changes with time, creating accelerating electric and magnetic fields that propagate away as electromagnetic waves. The antenna is the radiating element of a radio system; it converts electrical energy into propagating energy in space. The transmitter provides the power, but it’s the antenna that actually emits the radiation. The transmission line just delivers power and matches impedance, while the receiver is meant to capture energy from space and convert it back to electrical signals, not radiate.