Essential Guide to RF and Wireless, The

ANTENNAS

Block Diagram

Figure 3-3. Block diagram of an antenna.

This first device is called an antenna (see Figure 3-3). If you only learn one thing from this book, learn this: Every wireless system has an antenna. You may not see it, you may not recognize it, but it is there. The antenna's job is very simple—it converts electrical signals flowing down a conductor into airborne waves (in a transmitter) or it converts airborne waves into electrical signals flowing down a conductor (in a receiver) or both. It is the heart of the wireless system: no antenna, no wireless communications. Visually, it can be viewed as airborne waves entering (or ...