Sensing the World Around You

Radio Astronomers use the radio frequency portion of the Electromagnetic spectrum in their research. However, they are not the only ones that use this resource. Most people use this portion of the spectrum to send and receive information every day. For example, if you use wireless internet, make cell phone calls, send or receive text messages, or use a garage door opener, you are using radio frequencies. The previous sentence mentioned a few everyday uses of the radio frequency band, but the demand increases yearly. However, this portion of the spectrum is small, ranging from 1 to 3000 GHz. While it may be challenging to comprehend how small that is, it is easy to understand a limited resource with too many users. 


Diagram courtesy of Freepik (

Imagine you are at the beach. If you arrive early in the morning, there aren't many other people. You can spread out your belongings and throw a football without bothering anyone else. As the day continues, it becomes more and more crowded. If it is an exceptionally lovely day, it can become so crowded that you can hardly move without bumping into someone. Your actions become severely limited due to the presence of other users. So it is with the radio frequency band. As new uses are developed, or existing services expand, the less each user can do without being impacted by the actions of others. Therefore, the radio frequency band of the EM spectrum is a limited resource that must be managed wisely for the benefit of all.

There is an opportunity for you to be a scientist. To manage the spectrum so that everyone benefits, we must first understand the geographic locations and times of day when the radio frequency band is being used. You can help with this task. At the bottom of this page there is a button that will take you to a page of activities that guide you in collecting data on radio frequency use. This information will help us better understand how the radio band is being used in your area.

RTL SDR Activities