What are the key components of a secondary radar system?

• A. Transmitter, antenna, decoder
• B. Interrogator, antenna, transponder, decoder, radar display
• C. Antenna, receiver, display
• D. Transponder, receiver, monitor

Answer: (B)

A secondary radar system consists of several key components that work together to enhance aircraft tracking and identification. The correct choice highlights the following essential elements:

• Interrogator: This component sends out signals to interrogate aircraft transponders. It is responsible for actively querying the transponder for specific information, such as identification and altitude.

• Antenna: In both primary and secondary radar systems, antennas are crucial for transmitting and receiving signals. In a secondary radar system, the antenna is involved in both sending the interrogation signals and receiving the transponder responses.

• Transponder: This device is installed in the aircraft and responds to the interrogation signals from the radar system. When the transponder receives an interrogation from the interrogator, it transmits back coded information that may include the aircraft's identification (such as flight number) and altitude. This capability allows air traffic controllers to effectively track and manage air traffic.

• Decoder: This component interprets the signals received from the transponders, converting them into meaningful data for air traffic controllers to use for monitoring the aircraft's position, altitude, and other information.

• Radar Display: This terminal presents the decoded information visually to air traffic controllers, allowing them to see