What is Spectrum?

What Is Spectrum?

In the context of mobile devices, “spectrum” refers to the radio frequencies that wireless signals travel over. These signals are what enable us to make calls from our mobile devices, tag our friends on social media, request ride share services, pull up directions to a destination, and do everything on our mobile devices without needing to be plugged into the wall. The frequencies that we use for our smartphones are just a tiny portion of the larger electromagnetic spectrum.

All wireless technologies use some portion of this limited and highly precious spectrum.

Much like real estate, there is only so much frequency that exists that is best suited for fast, long-range communication with mobile devices. The more adjacent radios using any given spectrum, the more difficult it is to send and receive messages over those same frequencies. This can be analogized by shouting in a room; the more people that fill the room and speak, the harder it is to hear each other and the louder we need to talk to be heard.

To solve this overcrowding problem, parts of the spectrum are divided into “bands” that are then auctioned off by the Federal Communications Commission (FCC) to commercial companies so that they can use them. Once a company has rights to this spectrum it is then considered “licensed” to them. All modern cell service providers have bands that are within the frequency ranges of 700-39000 Mhz (see figure below).