The Reality of Radio: How Solar Interference Affects Communication
RF in Film: “Frequency” – A Kernel of Truth Plus Time Travel
As a Ham radio enthusiast, I love movies that feature Amateur Radio. While the movie Frequency required a suspension of disbelief (talking between the past and the present via Ham Radio is not feasible), it was still very entertaining. However, a solar storm will not cause a communications time warp. Still, there are several solar effects that radio amateurs are familiar with.
How Does Solar Interference Impact Radio Communications?
The sun, a continuous thermonuclear explosion held together by its gravity, creates a complex interplay of fusion processes and electromagnetic field swings, making it highly unpredictable. Even during periods of calm, the sun emits a vast stream of particles known as solar wind. This ionized “fluff” interacts with the Earth’s magnetic field, altering the ionosphere above the stratosphere.
You can find a technical discussion of the sun’s effect on the ionosphere from ARRL here.
Occasionally, the sun releases a larger-than-normal blast of charged particles known as a coronal mass ejection (CME). Radio propagation can improve when a CME is directed at the Earth, enabling distant communication or worsening, resulting in radio silence.
Several years ago, I decided to test an antenna tuned to the 10-meter Amateur band (around 29 MHz). I performed my tests at night, assuming the 10-meter band would be “closed,” meaning there would be poor radio propagation, and anyone listening would likely be local. Given my location, there were very few people active on 10 meters. You can learn more about the use cases for different waves and frequencies here.
After announcing my callsign, I began my tests. To my surprise, another Ham with a strong signal responded. I initially thought I had encountered a rare local operator. However, when I asked where he was located, I was shocked to learn he was on the East Coast! With the three-hour time difference, he was even more surprised to find out I was on the West Coast. Clearly, the sun was playing its usual tricks on radio waves.
However, if solar activity becomes more intense, it can lead to complete radio silence. The overwhelming influx of charged particles can strip the ionosphere of its ability to support communications, typically coinciding with TV meteorologists predicting spectacular auroral displays.
Mobile networks and the complex radio and computing systems they depend on face many vulnerabilities beyond just solar wind. You can learn about the challenges modern networks face here.
Are Critical Communications Systems at Risk of an EMP Event?
In some cases, larger solar outbursts can have more severe consequences. An intense solar blast interacting with the Earth's magnetic field and ionosphere can create an electromagnetic pulse (EMP). The effects of an EMP can range from power grid disruptions to severe damage to electronic systems. Read more about preparing EMP-related communications failures on our blog. While there have been several EMP-related power grid failures over the years, none have been large enough to destroy major electronic infrastructure—at least not yet. The last significant event of this kind occurred in 1859, known as the Carrington Event, which you can read about here.
So, while the sun may not allow communication between the past and the present, it certainly has a tremendous impact on Ham Radio and, in extreme cases, other electronics.
Curious on how we can help secure your communications systems from EMP disturbances? Schedule a free consultation with us today!