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Wireless-Friendly Microwaves

Posted by michael on from the press-enter dept.

Makarand writes "According to this article on ABC News, scientists at the University of Michigan in Ann Arbor have stumbled upon a simple and elegant solution to keep your kitchen microwave from becoming a noisy nuisance to your home Wi-Fi network. They found that they could focus the microwaves into a single frequency and reduce noisy microwave emissions by placing ordinary magnets in specific patterns along the magnetron . New techniques to reduce microwave interference will be needed when Wi-Fi enabled entertainment systems will allow digital audio and video to be transmitted to different rooms of a house wirelessly. Packet drops in such a sytem would degrade the video and audio experience."

3 of 119 comments (clear)

  1. pdf here by maharg · · Score: 5, Informative

    Low-noise microwave magnetrons by azimuthally verying axial magnetic field - here

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  2. Re:Or.... by Rosco+P.+Coltrane · · Score: 5, Informative

    When you hit water with it, it will agitate the molecules and things get hot and cooked

    You seem agitated and cooked enough without microwaves.

    The difference is in power and concentration : a microwave oven is minimum 700W, concentrated on a lump of water, whereas an 802.11b is 100mW radiated in all directions. You'd need hundreds of wifi cards doing denial-of-services around a cage to even start incommodating the hamster inside.

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    "A door is what a dog is perpetually on the wrong side of" - Ogden Nash
  3. Re:Or.... by eggboard · · Score: 4, Informative

    2.4 GHz is not the resonating frequency of water. That's way way up in the GHz chain. 2.4 GHz was chosen because that band is the junk band in which unlicensed users are subject to interference as part of the spec.

    Microwaves work by oscillating water molecules, which are dipole. The magnetron cycles 2.45 billions times per second, which twists the water molecules. The interior of a microwave oven is coated with a microwave-reflecting material which allows a single beam to essentially paint the three-dimensional interior.

    So many people write that water resonates at 2.4 GHz. It's just not true. Here's a nice explanation of how it works.

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    Freelance tech journalist for the Economist, MIT Technology Review, Macworld, and others