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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."

9 of 348 comments (clear)

  1. All 2.4Ghz devices are unlicensed! by tjhayes · · Score: 5, Informative

    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.

    1. Re:All 2.4Ghz devices are unlicensed! by vlm · · Score: 4, Informative

      By definition any device operating in the 2.4GHZ UNLICENSED BAND is an unlicensed device!

      Close, but not exactly correct. Technically if you get a amateur radio / ham radio license you can operate on a secondary basis in that band up to 1500 watts as per FCC 97.301 with special notice of 97.303(j)2(iv) and 97.303(j)2(B). Note that there is a heck of alot more to following FCC part 97 than just these two little sections. You probably mean any device operating under FCC unlicensed rules is an unlicensed device, but thats not saying much, more or less?

      (B) Amateur stations operating in the 2400-2417 MHz segment must accept harmful interference that may be caused by the proper operation of industrial, scientific and medical equipment.

      (iv) The 2417-2450 MHz segment is allocated to the amateur service on a co-secondary basis with the Federal Government radiolocation service. Amateur stations operating within the 2417-2450 MHz segment must accept harmful interference that may be caused by the proper operation of industrial, scientific, and medical devices operating within the band.

      http://www.arrl.org/FandES/field/regulations/news/part97/

      It's non unusual for multiple services to be allocated on one frequency or frequency band with some being licensed and some not being licensed and some being primary allocations and some secondary allocations.

      --
      "Science flies us to the moon. Religion flies us into buildings." - Victor Stenger
  2. Re:Channel 14 by phoxix · · Score: 5, Informative
    Channel 14 is entirely illegal to use in the USA (and many many many other countries) because it exists outside of the 2.4Ghz spectrum that is allocated for consumers to go nuts on. So yes, you're Wifi will be awesome because nobody is using that spectrum .... but you'll really piss off the FCC, ask your local HAM why this is a bbbaaaddd idea.

    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 ...

  3. More PERTINENT Post... by TrisexualPuppy · · Score: 5, Informative

    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!

  4. Re:You know what that means... by KillerBob · · Score: 5, Informative

    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
  5. Re:Baby Monitors by c0p0n · · Score: 4, Informative

    You are right sir. We can be proud of our British offspring.

    --

    Your head a splode
  6. Re:Why 2.4GHz? by marquis111 · · Score: 5, Informative

    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.

  7. "Unlicensed"? by John+Hasler · · Score: 5, Informative

    > 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.
  8. Re:You know what that means... by Maximum+Prophet · · Score: 4, Informative

    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)