What are the three essential parts of a complete antenna system?

A complete antenna system is fundamentally comprised of three essential parts: a coupling device, feeder, and antenna. The coupling device serves the crucial role of connecting the antenna to the transmission line, ensuring effective transfer of electromagnetic energy between the two. This might involve components like baluns or matching networks that optimize the impedance and facilitate better energy flow.

The feeder, or transmission line, carries the signal from the transmitter to the antenna and vice versa, depending on whether the system is transmitting or receiving. This part of the system must maintain signal integrity and minimize loss over distance, which is vital for maintaining efficiency in both transmitting and receiving operations.

Finally, the antenna itself is the essential component that radiates the electromagnetic energy into the atmosphere (in the case of transmission) or captures the incoming signals (in the case of reception). The design and characteristics of the antenna directly influence performance factors such as gain and radiation pattern.

The other choices include components that serve different functions within the realm of electronics but do not represent the fundamental aspects of an antenna system. For example, amplifiers, tuners, transmitters, microphones, speakers, and mixers are vital in their respective electronic systems, but they don’t fit the specific parameters of an antenna's function and structure.