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Xbox 360's Jamming Wireless Signals?
WirePosted writes "A report has emerged suggesting the Xbox 360's inbuilt wireless system for communication with wireless controllers and headsets is transmitting over a wide area of the 2.4Ghz spectrum, causing interference to WLAN's and other 2.4Ghz devices."
I would think we would have heard of this problem long before now. There are million of these units and when they are not displaying the red ring of death, you think this problem would be shutting down WLANs worldwide generating numerous WTFs. Microsoft also sells its own USB wireless adapter for the XBOX 360. You think the wireless adapter would be nuked by the wireless controller if this was the case.
Strange women lying in ponds distributing swords is no basis for a system of government.
Just a little anicdotal evidence but I have a 360 in the same room at my PC which is on wireless and two access points in that room as well. They all work fine at the same time.
Something along the lines of:
(1) Tolerate interference from other devices. (2) .... something else that I forget....
You see, the FCC does not want to have to certify that each and every $3 wireless mouse keeps its emissions within 0.2 KHz of 945.343 MHz at a field strength of no more than 330 microvolts / meter.
Welcome to the Republican Spectrum of the Future.
It's bad because 2.4 Ghz is radio, carrying digital info, which due to the nature of the produced sign wave results in a signal distortion more commonly known as "bleed over". Without the ability to separate the signals by a large frequency, digital over analog bleeds all over the place.
The hell? There is nothing magic about digital data that means you can't bandwidth-limit the outgoing transmission. There are plenty of digital radio protocols that use a very well defined slice of bandwidth, without any more bleed over than traditional AM or FM radio analog broadcasts. Just because the signal represents digital data doesn't mean you have to use square waves or something.
I suppose we should all be thankful that radio engineers are better educated than the average Slashdot poster...
(Of course, it's entirely possible there's something broken about the XBOX radio. It's also entirely possible it's just a spread-spectrum transmitter doing exactly what it's supposed to do in a largely unregulated piece of spectrum.)
WiFi refreshes so often that most people dont notice the significant proformance drop
their internet connection is almost always the real choke point anyways.
This isn't really new news as shown by this article from 2005. It talks about Wal-Mart's problems with some of it's 360 kiosks causing problems with their wireless inventory system.
I know we're supposed to hate MS and love the competition (and I do), but my wife claims that the Wii is also messing up the WiFi signal to her laptop.
or are you just happy to see me?
A small college is experience problems with their new wireless network equipment in the presence of a few xbox's. however, apparently all over the rest of the country, in huge universities with thousands of xbox 360s... there's no problem whatsoever. the only bit that doesn't fit with this is that they said the IT staff had issues using their bluetooth headsets. now, the only comment i can make on this is that i think they have cheap bluetooth headsets. they said the 360 makes the signal even when its not turned on... just plugged in. i have both a ps3 & 360 virtually one on top of the other (a shelf plus a few inches of space in between) and the ps3's bluetooth controllers work just as fine as they did before i got the 360. so, all in all, i think this is a load of bull. the 360 has been out for way too long for this to not have been noticed. i think something else is screwing with their headsets & wireless network. or maybe its just the wireless network thats screwing with the headsets and they're looking for a scapegoat.
There's a lot of stuff that operates in this range. From the article itself it merely says: "It's not clear whether the signal disrupts the college's WLAN access points or students' wireless notebooks. There is some anecdotal evidence, however, that it at least affects other radios in the same 2.4GHz band." Basically the article just talks about a 'strange' 2.4GHz signal that they found and didn't know where it came from. Turned out it came from the XBox 360 (and that is admittedly his "best guess"). No evidence or claim in the article that it is interfering with any WLANs, he basically just says they need to do more 'systematic testing' (that is, putting a bunch of 360s in the room to see if they can cause interference).
Nothing to see here...
This is why I hate everything that's wireless. Devices interfere with each other, they have to be recharged all the time, and it's slow! I propose a revolution, a revolution where devices don't interfere with each other, they don't need to be recharged, and is fast! I propose the use of thin threads of copper for signal transmission and power supply. In fact, I am inventing the next BlackBerry killer. Imagine a phone which never drops a signal, never requires charging, and can transfer data at 1gbps. That's right, a phone that's wired! Now, I just need to make sure NTP doesn't sue the crap out of me for wired e-mail.
Seriously. Come on.
Ideology breeds Hypocrisy. Just how much is up to you.
For the record, my Wii seems to have problems with the wireless. If I leave the WiiConnect24 on, after a couple days the wireless router stops responding, and it doesn't kick back on until I turn off the WiiConnect24 , even after I reboot the router.
Anthropic principle: We see the universe the way it is because if it were different we would not be here to see it.
My license reads technician too. What is this "sign wave" you're talking about? Is it a stop sign? A sign from on high? I'm sure you can connect the dots in a QAM constellation to make many different signs.
And people laugh at me for wearing a tin foil hat! YOU AREN'T GETTING MY BRAIN WAVES BILL!!
geek n performer who performs morbid or disgusting acts, as biting off the head of a live chicken
Tell me again when you live in an apartment building. I can currently see 43 wireless networks in iwlist. I actually see two outside the normal range (it's full of tech-savvy college students anyways). Wireless is useless here, I even bought a signal-boosting router, but it still only works reliably within 20 feet of it. All my computers have ethernet hookups, my friends have to deal with the wireless shit all the time because they're lazy and don't want to string wires.
A radio technician license doesn't make you an expert. That's quite clear from your post.
Try being a Technology Director, with a radio license, and an EE from an excellent engineering school, plus 20 years experience in digital communications. I can personally tell you that it still doesn't make one an expert.
However, I can tell you you're way off base in your post. The whole point is that 2.4 GHz (not Ghz, BTW) is that it isn't managed! It's up to everyone to pretty much fend for themselves!
Good grief. No wonder it's a "mess" when people like you start talking about "sign" waves.
Minor detail that you can't legally use that channel in the United States (or Canada?). Granted, the odds of getting caught are next to nothing, but I don't think this is a viable "fix" for anybody in the business world.....
I want peace on earth and goodwill toward man.
We are the United States Government! We don't do that sort of thing.
Wouldn't it have been better to say "I hate everything that's unlicensed wireless"?
Devices interfere with each otherI've never had an interference issue with a cell phone. Of course my cell phone is using a licensed band......
they don't need to be rechargedThis is the single reason why I've never bought a bluetooth headset. Yet another device to charge. Somebody needs to give me a rational explanation for why mini-usb hasn't become the charging standard across the industry. Motorola is using it for all of their stuff (phones and headsets). Why is nobody else? Yes, I mean you Nokia.....
I want peace on earth and goodwill toward man.
We are the United States Government! We don't do that sort of thing.
Fine, then. How would viewing a plot of a sine wave tell you anything useful? Wouldn't you rather look at the frequency domain to see how well your equipment is staying within its part of the spectrum? Are you sure you know what you're looking at? You may want to save the HAM and IT rank-pulling for the users in HR.
"Devices that use spread spectrum do not cause interference with each other"
There, fixed that for you.
Seriously, anybody that has ever tried to use an analog 2.4Ghz cordless phone near a busy wi-fi network knows that they do cause interference. Hell, I can even tell when my wi-fi has a burst of activity if I'm using my bluetooth headset.... and bluetooth is supposed to avoid channels that are in use.
I want peace on earth and goodwill toward man.
We are the United States Government! We don't do that sort of thing.
I'm not saying that there isn't a problem. The article reads more like an advertisement in spots, but they do give a modest amount of technical info -- enough that I'm willing to believe the problem is real. It appears that the spread-spectrum controller is interfering with the WiFi signal. That's not overly surprising, but it has absolutely *nothing* to do with the fact that the data is digital. It has everything to do with the fact that these two devices are using each other's bandwidth and not handling the interference well, which is unsurprising given the relatively unregulated nature of the 2.4GHz band. The intereference could just as easily be caused by an analog source as a digital one.
Also, unless you're really experienced at it, you can't tell a clean, bandwidth-limited signal by looking at it in the time domain -- you need a spectrum analyzer. (If you're really experienced, you'll do ok, but the spectrum analyzer is still important.) Furthermore, "spread spectrum" is not the same thing as "not clean" -- not in the slightest. From the perspective of the other device, though, they may produce similar results (undesired interference).
The lesson here is not that the radio engineers are screwing up. (They might be, but there is no evidence presented to that effect.) Rather, it is that using multiple different transmission schemes in the same band without any coordination is likely to cause problems. And really, that's not exactly a surprising result. If you want someone to complain at, complain at the regulators for not providing more bandwidth with better negotiation protocols mandated.
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You are right about 2.4 GHz devices interfering with each other. That's about it.
First: Wi-Fi devices may be assigned "static channels", but these are not minimally wide frequency bands as you imply. In fact, the channels are 30Mhz wide and contain spread spectrum signals. Channel 1 overlaps channels 2 through 5 enough to cause interference.
Second: Digital modulation techniques need not "bleed over" significantly past the bandwidth required to carry the information (i.e. potentially less than analog transmission of the same information). For example, psk31 is a digital mode with a bandwidth of about 31Hz.
Third: Modulated signals are necessarily not sine waves. Especially signals designed to look like noise (n.b. Wi-Fi is meant to look like noise across 30MHz of spectrum). You will see changes in frequency or phase (I'm not certain which). If individual cycles of the 2.4GHz waveform you saw looked rough then you made a mistake sampling the signal. Visible distortion of a single wave so far out of bad it would not affect any 2.4GHz devices.
BTW, my license says "Extra".
Every time I start to have faith in humanity, I ruin it by driving to work between 7 and 8 am.
Try locking your access point to 802.11b-only mode and see what that does.
I've noticed the exact same problem you describe with a lot of 802.11g chipsets (Intel Pro/Wireless being the worst offender in my experience). Watching the devices they seem to switch speed rates constantly up and down for no obvious reason. Every single time a rate change happens the network communications stop for at least a few seconds. Eventually they just stop communicating altogether until the client is reset.
Once locked to 802.11b all of the devices remain connected at 11mbps. This should be a viable solution for you if you only need wi-fi to connect to the internet. 802.11b should provide at least 5.5mbps of usable bandwidth for TCP and upwards of 7mbps for UDP. If your internet connection is faster then that then I don't have a lot of sympathy for you, cuz mine isn't ;) If you need faster wireless (i.e: LAN file transfers) then you might need to look at finding different client cards or access points until you get a pair that communicates reliably.
The other thing I've noticed is that some of the Intel Chipsets try to implement a proprietary power saving scheme that causes issues with a lot of APs. You can usually disable this feature, though the specifics of how to do so would depend on which OS and drivers you are using.
I want peace on earth and goodwill toward man.
We are the United States Government! We don't do that sort of thing.
An idle wi-fi network doesn't make the cordless phone inoperable (though hearing the clicks every time the wi-fi network beacons is annoying), but a network running some decent traffic load will render the phone next to useless.
but such as the life of using an FCC part 15 device in the ISM band...Indeed. I'd like to see the FCC open up more unlicensed bands but limit each band to a certain type of device -- i.e: this band for DSSS devices, this band for FHSS devices, etc, etc. Most of the interference with 2.4Ghz seems to be related to devices that use different types of air interfaces. For the most part those using the same interface co-exist without issue.
I want peace on earth and goodwill toward man.
We are the United States Government! We don't do that sort of thing.
"Work is the curse of the drinking classes." -Oscar Wilde
Anecdotally, I have my doubts. I have a pretty complex network - the office upstairs (with 4 LAN devices, including a Polycom phone) is connected via a wireless bridge between upstairs and downstairs with two Linksys routers. Where does my router downstairs sit? Right on top of my XBox 360. I VPN without a hiccup, use the phone without a hiccup, and stream music, whilst my partner and her friends have played games downstairs on the 360 for hours and not once have I ever seen the network hiccup as a result.
True, provided that you can prove that a device covered under part 15 was indeed causing actual harmful interference, and not just transmitting as designed. Until amateur radio receives primary allocation status of its section of 2.4GHz, I doubt that any ham would be very successful at kicking a part 15 device off their local airwaves.
Amateur radio has to comply with part 97, and the unlicensed devices have to comply with part 15, but the secondary allocation status for amateur radio (on 2.4GHz) puts the two almost on a level playing field as far as who has the "right" to be transmitting.
If there is one thing I have learned about dealing with radio interference and electrical noise in general, it's that it is unpredictable and depends on far stranger details than you would think. That you don't have trouble surprises me even less than that some people do. If it were exceedingly common I'd be surprised -- I imagine MS tested at least a handful of simple, obvious cases. Of course, we don't have proof that the XBOX is at fault, but I wouldn't be surprised either way. Whether it's reasonable to lay blame on MS for it is another question... Sometimes these things don't get along, and as long as everything is playing by FCC rules its hard to lay blame on one party.
Everybody has to make devices that use the same spectrum, meaning everybody wants to make devices that utilize that spectrum for the sake of cross-compatibility. This would be a non-issue were it not for 99% of home wireless networking hardware supporting b/g exclusively.
I'm looking forward to the IEEE finalizing 802.11n if for no other reason than because I'll finally be able to get 5 GHz access points without paying through the nose for office equipment.