Understanding the RF spectrum

Invisible radio waves are all around us. We take them for granted. To understand wireless communications, in general, it is a good idea to take a look at the radio frequency spectrum. The following diagram is a graphic describing this spectrum:

As you can see, there are frequencies ranging from 3 kHz all the way up to 300 GHz. The corresponding wavelengths are shown at the bottom of the graphic. The RF spectrum is subdivided into the following bands:

• VLF: Very low frequency
• LF: Low frequency
• MF: Medium frequency
• HF: High frequency
• VHF: Very high frequency
• UHF: Ultra-high frequency
• SHF: Super high frequency
• EHF: Extremely high frequency

Let's take a deeper look at each of the frequency bands.