Electromagnetic interference (EMI) affects technology significantly, yet it’s practically invisible. To give a broad definition, electromagnetic interference takes the form of emitted waves at a certain frequency that disrupt separate waves of the same frequency. In layman’s terms, a signal that’s too similar to another nearby signal stops working. This is very important for companies making and attempting to protect devices. Here’s a list of three of the most interesting facts about electromagnetic interference.
EMI Is in the Air and Everywhere—Sort Of
Many devices emit electromagnetic waves, but it can be difficult for us to imagine these frequency streams because they’re invisible to our eyes. In reality, these electromagnetic waves crisscross everywhere. However, they don’t travel through the air as you might imagine. For instance, sound waves(which are mechanical waves) can travel through mediums such as air, water, or solids, but electromagnetic waves do not.
There Are Three Kinds of EMI
Another interesting fact about electromagnetic interference is that there are actually three EMI varieties. First, inherent EMI emits from the device itself, meaning the device’s emitted frequency can affect its own functioning. Second, the world and its natural events (such as storms) also emit EMI. This type of EMI—known as natural EMI—can extend beyond the Earth—large celestial bodies in space also disrupt certain waves. Finally, man-made EMI comes from other devices and structures, ranging from large power lines to small pieces of tech.
Militaries Can Weaponize EMI
Finally, some militaries weaponize the disruptive potential of EMI to cause enemy technology to fail. Some militaries employ high-altitude electromagnetic pulses (HEMP) to impair enemy communication systems and gain the upper hand. Some parties use it for terrorist activities as well. This is why military technology must come with
certain shielding protections that essentially render weaponized EMI harmless.
