How Does an Antenna Work: A Brief Explanation

Antennas are an integral part of modern communication systems, but how do they work? Don, an antenna designer and tester, helps us understand the basics.

The first thing to understand is the coaxial cable, the wire used in antennas. Unlike normal power cables, coaxial cables have a shield outside, an insulator, and a center conductor that runs power to the antenna. This wiring is important because if two pieces of wire are side-by-side, the current flows cancel each other out. However, the current flows in the same direction across the plane in a coaxial cable, allowing it to radiate energy into space.

A dipole antenna, like the ones on FM stereos, is a simple example. By splitting the wire in two directions, it generates RF energy that radiates out like a field. Most antennas work similarly to a dipole antenna and have radiated energy on both sides.

But how does an antenna receive energy? It captures the energy that is radiated out and transfers it down to the feed point. From there, it can be run into an amplifier or plugged straight into a stereo system.

Antennas are an essential component of modern communication systems, and understanding how they work is critical in the field of communication technology.