questionswhy do i lose wireless network when my microwave…


take your router out of the microwave, genius.


Many microwave ovens also emit frequencies in what we engineers call the "unlicensed band", and that can potentially cause interference with the 802.11 devices (no worries, it is not dangerous to health). It is rare that you would completely lose your wifi connection, since the protocol does have built-in resilience to these interferences. However, your throughput could drop significantly.

Since you asked about microwave, a microwave has a 50% duty cycle roughly meaning that it's transmitting half of the time), That means that potentially, the throughput of your router (since it's sharing the same frequency band) could be cut to half. If you already had weak signal in certain parts of your residence, the speed may drop to a point where you think it has completely "dropped".

Without knowing the layout and the signal strength of your place, this is the best educated guess I can provide. A grounded tin-foil may help, but only if you completely cover the microwave.


Wow, ^^^^ That guy's pretty smart...until the end when he tells you to put tinfoil in your microwave. I REALLY thought he was going to say tinfoil hat...and as such I am disappointed in his answer. Totally accurate and much more helpful than anything I've ever said, but I really think he missed a tinfoil hat reference. And isn't that more important?


I don't know nearly as much as @lll0228, but putting the two in different rooms/ just increasing the distance between the two could help as well. I've actually heard of this before, and that did seem to work for some people. But then again, that depends on the strength of each one and the layout of your home. If it's a really strong microwave and you have a fairly open house, it might not make a difference. But if you can manage to get a good distance and a few walls in between the two, it might have some potential.


Microwave ovens interfere with 802.11b/g (ie: 2.4 GHz) frequencies. This can also interfere with 802.11n which can use either 2.4 or 5Ghz frequencies.

If you want to avoid this problem completely, go to 802.11a frequencies (5Ghz) and the problem should disappear, or if you want 802.11n speeds make sure its using the 5Ghz frequencies.

Both your client and your router will need to support the new frequencies. Note that 5Ghz can give you a shorter range than 2.4Ghz, although you should get faster speeds.


Perhaps you can try changing the channel on your wireless router? This helped alleviate some interference a friend had from his TV / Wireless speakers.


@jgrz0610: No no, I meant putting tin-foil grounded, wrapping the microwave on the outside. LoL

But even that's pretty much useless. :)


Btw, when people talk about "tin-foil", I think it mostly means building a Faraday's Cage. But tin foil isn't that effective (you need thickness and full enclosure for effective blocking of electromagnetic waves).


as @cnorborg: said...

"Microwave ovens interfere with 802.11b/g (ie: 2.4 GHz) frequencies. This can also interfere with 802.11n which can use either 2.4 or 5Ghz frequencies."

However I say if you want to avoid the problem dont switch your router over to 802.11a frequencies. Switch your Microwave over to 802.11a frequencies. Thats where the magic is at.

Trust my opinion I work in Networking Services IT ;)


@killswitchdh: if you put your microwave oven an a plate that vibrates @ 2 cycles per second, wouldn't that double the leakage output frequency :P

trust MY opinion, I am from the internet


For those that don't understand how wet killswitchdh's comment is, here is a longer explanation. Microwaves operate at about 2.4Ghz because that has been found to be one of the most efficient frequencies for creating heat by being absorbed by the liquids and fats in the food. This is also why 802.11b/g radio's have a big problem operating in wet environments. For instance, if you can normally get reception of your wireless in your garage, but not during a downpour, its because of this. Or if you deploy wireless in a warehouse during a dry time of the year, and it stops working well when the humidity rises, it can be because the boxes or items your storing on the shelves start absorbing the humidity and interfering with the radio waves.

5Ghz frequencies pass easily through water without being absorbed, so because of this microwave ovens would be extremely inefficient if someone tried to make one that operated in that range. Makes for awesome wireless networking though!


How far is your microwave from your wireless router? Are you sure your wireless signal is lost throughout the entire house, or is it just on the device that you are using while standing next to a working microwave? Large microwaves can affect your wireless signal when standing anywhere near them. If your microwave is affecting the entire wireless signal then your router is too close to the microwave.


the same problem will occur not only for network devices but also for wireless house phones or any other items on the same bandwidth.

assuming the router is an 802.11b/g device, change the channel to a different frequency. a minimal change from 1 to 14 (2.412 to 2.484) may be enough to alleviate the issue. also (as others have indicated as well) , move the router to increase the distance between the microwave and router.

if those options don't work, a more expensive solution would be to upgrade the router and all NICs to use 802.11n. A dual band device providing 2.4 and 5 gHz would be most ideal with the router using the 5gHz range, to avoid the microwave using the 2.4 bandwidth. with this change, you are also more up to date with technology too (in a sense).

using 802.11a, while an option, wouldn't be very feasible as it would be taking a step backward instead of forward.

just my .02


You can get 802.11n routers with only 5Ghz too, I suppose it would depend on your needs and budget. Like you said, 802.11a is old technology, so probably fairly cheap these days, and while you won't get things as fast as 802.11n, it will be faster than the 2.4Ghz frequencies, but at a shorter range.

802.11n mainly gets its faster speeds through using multiple radios/antennas at the same time operating in parallel on different frequencies. I've heard some 802.11n implementations do this by using both 2.4 and 5Ghz simultaneously, I would think microwave ovens could still interfere with this too although I have not experienced it. If you get a 5GHz 802.11n router with a single antenna, I would think it would be not much better than an 802.11a router.

I suppose you could always get one of those flash ovens, I think they work off infrared or something like that?


@jockovonred: I had a client who would complain of bad/intermittent wireless networking in the office. I installed the WAP (this was when there was only 802.11b 5.5/11 Mb/s) and was confident in it's function (Aironet before Cisco purchase). Come to find out, they had just added a cordless phone to their phone system. Placed it near the WAP antenna (a 5.2dbi omni). They would lose connection when the phone was used due to its 2.4GHz operating frequency. I actually fixed it by changing from channel 1 to 11.

@cindihoward: you could change the channel of your router to one extreme or the other (if you're on 1 go to 11 and vice versa) If you are on channel 6, take your pick, 1 or 11.


@cnorborg: Exactly. Great solution. And bad of me not to think about the non-microwave frequency that's available only for wireless network now. Ick!

Or if the OP is very technically inclined, build a Faraday's Cage. :)


also, please quit using your router to interfere with my pacemaker.