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Baby Monitors Killing Urban Wi-Fi
Barence writes "Baby monitors and wireless TV transmitters are responsible for slowing down Wi-Fi connections in built-up areas, according to a report commissioned by British telecoms regulator Ofcom. The research smashes the myth that overlapping Wi-Fi networks in heavily congested towns and cities are to blame for faltering connection speeds. Instead it claims that unlicensed devices operating in the 2.4GHz band are dragging down signals. 'It only requires a single device, such as an analogue video sender, to severely affect Wi-Fi services within a short range, such that a single large building or cluster of houses can experience difficulties with using a single Wi-Fi channel,' the report claims."
Does the article not realize that "Wi-Fi" devices are also unlicensed? By definition any device operating in the 2.4GHZ UNLICENSED BAND is an unlicensed device! Wi-Fi devices have the exact same priority as any other device using this frequency band. And really, there's nothing wrong with this. Since this frequency band is unlicensed the FCC is basically saying "use at your own risk, anyone can use this frequency for any purpose they like, and there is no guarantee of any quality of service". If you want something that's more reliable and guaranteed to work shell out the $$$$ for some spectrum and equipment that works on a licensed piece of spectrum that you own.
That being said ...
Using channel 14 in the USA (and other non-channel 14 countries) can be done via a DD-WRT compatible router, and Wireless cards where you can change the CRDA to Japan (like Atheros cards that work with ath5k and ath9k on linux.)
The linux command to change your regulatory domain is:
bash# iw reg set JP
The issue with channel 14 is that it is reduced power, meaning in most cases you'll only get 802.11b speeds with it.
Now why something is critical as wifi has to exist with stupid consumer shit is the real crux of the issue ...
It kind of annoys me to see big rollouts using 802.11.
First there's the snowjob the ISPs give the cities to get the municipal monopoly, then there's snowjob the eager, wannabe-techno-savvy politicians give their constituents for giving away the farm to yet another municipal monopoly (where I live it was a sweetheart contract to provide in-care wireless to cops and city workers to prop up the ultimately unprofitable sale of wifi to end-users), and then there's the inevitable whining from users about why it doesn't work like the access point within 25 feet of them everywhere else they use 802.11, which they inaccurately call "wireless" and lump the in same category as cell phones, FM radio, etc.
Then we get to the point where providers using a technology not designed for lighting up whole cities start bitching about everyone else using "their" unlicensed spectrum....
So after reading the article, I can't really agree on this. I have "lots of EE friends in high places" and they also disagree to a large extent.
Back in 03 when I was deploying my company's first wireless networks, this article explained a lot.
And further reading here...funny how this has already been covered this year.
And remember, the ISM band *was allocated because of microwave ovens* as in...it wouldnt be fair to license out this band because it is interference prone, so they made it a sort of free for all...if a baby monitor is interfering with your cordless phone or WiFi, that is probably the least of your problems!
I have a Summer Best View baby monitor http://www.summerinfant.com/categories_products_view.php?id=322 that I found at Target and as much as I love this little device, it brought my wireless G network to a crawl. I could no more longer stream movies across my wireless. The camera end does let you choose between two frequencies and I found that if I change the channel on my router to 1 from the default 6 and changed the channel on my baby monitor, I have the speeds almost back to normal. I did have a problem with my wireless devices reconnecting and had to reconfigure most of them. I was really surprised that these devices were permitted to use the 2.4GHz frequencies, but at least I found a way to cope with it.
I just heard the police saying that they discovered a paedophile ring on Slashdot who were conspiring with a baby sitter to kill a baby called Wifi, purple monkey dishwasher!
It's no secret that 2.4G and 5GH devices screw with wireless networks... heck, I bet they also found that in dense areas, WIRELESS NETWORKS EFFECT THE PERFORMANCE OF WIRELESS NETWORKS! Guess what, so do microwaves!
Network and other data devices should 1) be relegated to dedicated frequencies, like TVs, radio, and phones already are. Restrict only data systems to that band. 2) narrower band restrictions should be employed (or expanded ranges) to allow more chanels to agregate in the same space. 11 chanels, including the crossover which really leaves us with 5-6 viable chanels, is not NEARLY enough... 3) Portable household devices (like phones, monitors, etc) and other wireless systems (home theatre speakers, game remotes, etc) should be relegated to their own bands not used for network/data.
I just moved into a new house. I bought a lot of new equipment to go in it. My new wireless phones are 8.2GHz. My HT rear speakers run on line-of-sight, not 2.4GHz like most. My Wifi runs on 5GHz (and also 2.4, but that's reserved for the guest network SSIDs which are disabled completely unless I have a guest). My baby monitors run in the 900MHz range. Everything that COULD be wired IS wired. As a coutesy, on the devices I can, I have turned down the gain so the signal is only clear to the distances required. (my wifi penatrates all my rooms at 4 or 5 bars at only 60% signal strenght, i have no need to be on wifi 250 feet from my house...).
There is no contest in life for which the unprepared have the advantage.
They could be in the same part of the spectrum, but designed by sane people. If your router is newer, for example, it probably supports frequency scanning and self-configuration for channel. Routers which have that ability will scan the usable channels, and pick the one that has the least interference, and are able to change channels on the fly when somebody opens up and starts cluttering your channel.
Likewise, higher end baby monitors are able to broadcast/receive on at least a dozen channels, and I've seen ones that are capable of using 48 different channels and more. These will pick a frequency where there's less interference in order to work.
You could be being affected by engineers who actually knew what they were doing when they designed your hardware, in other words. I know. it's rare. But things will be ok.
If you believe everything you read, you'd better not read. - Japanese proverb
WIfi IS stupid consumer shit. ;-)
There is currently a huge uproar over how the 802.11 wants to use 40MHz bandwidth leaving no space for other (arguably more critical) devices like 802.15.4 based sensors and controls.
Interestingly 15.4 can cope much better with filthy 2.4GHz radios as the modulation scheme is designed for robustness rather than speed.
Get you bandwidth hogging butts out of 2.4GHz.
> Why the heck are baby monitors on 2.4GHz anyway?
It is an unlicensed band. Anyone can use it, and no one can (legally) complain, since they "knew" that it was a free-for-all (it is hidden in the fine print in your router directions, probably).
> Why can't they operate on lower frequencies, like
> the 900MHz bands? 900MHz goes through walls better, too.
Because those are all licensed bands, with only the selected providers allowed to operate their (your cell phone can use it only to connect to a licensed provider) equipment in your area.
Isn't that what being part of the unlicensed, open, free spectrum means though? Anyone can use it for anything?
No, it only means that anyone can use it. There are still rules about how it can be used; it can't be used for just anything. for example, the maximum transmit power for 2.4ghz is something like 1 watt. If you transmit over that power, you're in violation and the FCC can shut you down.
Moderating "-1, Disagree" is simple censorship. Have the guts to post your opinion.
You are right sir. We can be proud of our British offspring.
Your head a splode
My old 915MHz WaveLAN network I still have set up at home hasn't been bothered at all by the baby monitors. Last I checked, 902 to 928 MHz is still open for unlicensed ISM use in Region 2.
> Because those are all licensed bands, with only the selected
> providers allowed to operate their (your cell phone can use
> it only to connect to a licensed provider) equipment in your area.
> Instead it claims that unlicensed devices operating in the 2.4GHz band are dragging down
> signals.
Um, WiFi devices _are_ unlicensed devices. They use the 2.4GHz band on the condition that they do not interfere with authorized uses of the band and accept any interference with their operation. Baby monitors have just as much right to use the band as do your WiFi devices and both must yield to authorized uses.
Warning: this article may contain humor, sarcasm, parody, and perhaps even irony. Read at your own risk.
Ack, I can't tell if you are joking or not.
Microwave ovens use this space, because water absorbs it very well. Because ovens use it, and atmospheric water absorbs these frequencies, the standards people knew it wouldn't be very useful for communications, so they made the band unlicensed for limited output power. (Microwave ovens are not supposed to leak, but sometimes they do. If your or your neighbor's microwave causes much interference, have it checked out, the leakage could be dangerous.)
Anyway, because this spectrum was unlicensed the free market took over, and tons of devices started to use it.
There's plenty of licensed spectrum that you can use, just get a license.
All ideas^H^H^H^H^Hprocesses in this post are Patent Pending. (as well as the process of patenting all postings)
I had similar problems with my Wi-Fi connection dropping and was finally fed up, so I did some research and found the MetaGeek Wi-Spy spectrum analyzer (ONLY $99-$199). http://www.metageek.net/ I ordered the $99 Wi-Spy v1, haven't received it yet, but I suspect that I have a neighbor that is using a 2.4ghz phone (in the Ch 1 range) that is causing my dropped connections.
My parents' cordless telephone kills the wireless every time it rings, and for as long as it's in use.
Sometimes.
I think it depends on the channel the router was using... it was set to automatically pick the "best" channel. Well, until the phone rang.
Changing the channel to a fixed value solved the problem, I think. Apparently the phone was only interfering on some of the channels' frequencies.
Alexander Peter Kristopeit bought his basement from his mommy for one dollar.
I love how the article makes it sound as if these devices are not "supposed" to be on the same spectrum as the Wi-Fi devices, which are also "Unlicensed" devices.
The ISM band is an unlicensed band that anyone can use, and you can't complain if someone interferes with you.
That's simply not true. Do you even know what ISM stands for?
Saying that the ISM band is unlicensed because there is no commercial interest in it is like saying that they don't build condos on artillery ranges because there is no developer willing to buy the property.
From CFR Title 47 Part 18: