When you start your microwave oven, do you lose Wi-Fi signal on a nearby device? Wi-Fi and microwaves both work at the same frequency, which can cause interference. But why?
Microwave and Wi-Fi Use the same unlicensed spectrum
in 1947, the International Telecommunication Union established the ISM bands, cards for Industrial, Scientific and Medical. The aim was to define which units would be allowed to run at certain radio frequency bands so that they would not interfere with other radio communications services.
The ITM unit designated the 2.4 GHz band as an unlicensed spectrum especially for microwave ovens. This band has three compelling features: It does not require much power to transmit, it is easy to contain, and with relatively lower power it can heat up food. All this reduced costs and barriers to entry for consumers.
As the ISM name suggests, the original intent was only for use in devices that did not provide communication. Over the years, the prospect of an unlicensed spectrum has been used beyond its original purpose, such as wireless phones, walkie-talkies and more recently Wi-Fi. The 2.4 GHz band was ideal with low implementation costs, lower energy requirements and decent distance capabilities.
Microwaves are not a Faraday cage; They leak
Everything that runs on the ISM bands should be designed for intolerances to avoid interference, and Wi-Fi devices have algorithms explicitly for that purpose. However, a microwave oven is powerful to overwhelm any nearby Wi-Fi signal.
Microwaves have shielding to prevent this, but they are not a perfect Faraday cage. A network window on the door prevents it. It's not uncommon to have a little leak from a microwave – just look at one that hasn't been cleaned for a while to see it. You will probably see dirt and grease on the outside that could only have come from inside food. If solid material can leak, it may also leak radio waves.
Microwave and Wi-Fi devices use an equal frequency to disturb the other. Your Wi-Fi will not make anything noticeable to the microwave oven, partly because of its shielding and partly because everything it tries to do is heat your food.
No Wi-Fi can't fix you
Wi-fi and Microwaves use an extremely similar radio frequency, but there are two significant differences: focus and power. A Wi-Fi router sends its signal omnidirectionally. This means that it sends it in every direction in a rough circle as far as it can. Your microwave oven, on the other hand, transmits its signal in a single direction, roughly to the middle of the oven. That signal continues until it hits a wall, bounces and returns (at a slightly different angle). It is not a perfect system because of the nature of the radio waves, and each microwave has hot and cold spots. Therefore, microwaves have spinning plates.
Microwaves also use more power than a Wi-Fi router; they usually generate 1000 watts of power. Conversely, a standard Wi-Fi router generates about 100 milliwatts (or 0.1 watts) of power. You need to increase the Wi-Fi router's power in about 10,000 times and limit the beam to have a chance to cook.
You probably do not need a new microwave oven
If you see disturbances, you do not need to change the microwave oven; Most likely the leak is small and not harmful to you. Wi-Fi is much more sensitive, and it doesn't take much to cause a problem. Instead of changing the microwave, you can move it. Alternatively, you can purchase a new Wi-Fi router that works on the 5ghz band. You will not only avoid disturbances from the microwave oven, but you will also prevent disturbances from your neighbors.
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