Electromagnetic interference

Electromagnetic interference (EMI), also called radio-frequency interference (RFI) when in the radio frequency spectrum, is a disturbance generated by an external source that affects an electrical circuit by electromagnetic induction, electrostatic coupling, or conduction.[1] The disturbance may degrade the performance of the circuit or even stop it from functioning. In the case of a data path, these effects can range from an increase in error rate to a total loss of the data.[2] Both man-made and natural sources generate changing electrical currents and voltages that can cause EMI: ignition systems, cellular network of mobile phones, lightning, solar flares, and auroras (northern/southern lights). EMI frequently affects AM radios. It can also affect mobile phones, FM radios, and televisions, as well as observations for radio astronomy and atmospheric science.

Recording of US House of Representatives debate on October 8, 2002, interrupted and distorted by electromagnetic interference from a solar flare at approximately 4:30p.m.
Electromagnetic interference in analog TV signal

EMI can be used intentionally for radio jamming, as in electronic warfare.

Interference by 5 GHz Wi-Fi seen on Doppler weather radar

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This article uses material from the Wikipedia article Electromagnetic interference, and is written by contributors. Text is available under a CC BY-SA 4.0 International License; additional terms may apply. Images, videos and audio are available under their respective licenses.