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WiFi, Light Bulbs, And The FCC
JFMulder writes "According to Cringely, 802.11 WiFi wireless networking is going to get in lot of troubles when Fushion Lightning starts marketting low-power light blubs which causes interferences with Wifi signals. Read about it at I, Cringely. Supposedly the new kind of light bulb is a real electricity saver and can wreck havoc to wireless networks in a half a mile radius. So what would you prefer? Wireless networks or low cost light bulbs all around the country to save more and more on electricity?" Update: 06/13 03:52 GMT by M : Cringely confused the FHSS-or-DSSS 802.11 standard with the DSSS-only 802.11b standard, but the general warning about the potential for interference is certainly troubling.
This was posted -- what, two or three weeks ago? Come on guys!
The old story even had a poster who mentioned that he'd used the lighting technology Cringley mentioned, and it's nowhere NEAR primetime, so it won't be causing probs for several years, if ever.
Light or WiFi? Light or WiFi?! Aaah, can't...choose...*head explodes*
Actually, I already have a few energy efficient lights around, and I don't really use WiFi, sooo... guess it doesn't apply to me.
Danish != nationality
Until the geeks of the world learn to curb their appetites for lower power and roaming Internet, we are going to see these clashes.
Unfortunately, it's likely we'll see the death of one or the other before the geeks ever learn to use what they are provided in moderation.
I have been pwned because my
Well the answer appears very simple to me.
If these lightbulbs are emitting RF in the 2.4GHz spectrum then when will some smart-assed entrepreneur come up with the dual-function lightbulb/WiFi node?
Half the guts is already there -- the transmitter.
If every household and business had these bulbs, think of the massive 802.11 network we could build!
Each bulb could become a node in a new, better, "brighter" Internet.
Okay so I'm kidding!
Of course if that doesn't work -- why can't they just use some sheilding on these bulbs? A very thin (transparent) metal-film conductive coating (of the type they use on LCDs) should do the trick quite nicely and at minimal cost.
could do without the lights and just rely on the glow from their monitor?
:)
12% of slashdot judging from the current poll: Preciousss, the sunsss hurtssss.....
802.11xx are doomed anyway, as long as the frequencies can be used without regulation. Yes, wlan shrinks cells automatically and delivers less when there is more users and traffic, and yes, you can "just" add network elements. However, when it really becomes a success story, it is doomed. WLAN with it's uncontrolled frequencies just will not work in very tightly populated areas if a significant percent of people begins to use them. And we don't even need any assisted interference to achieve the congestion.
the 2.4ghz band is a mess. cordless phones, video transmitters (X.10!), 802.11, and Bluetooth all share that band of frequencies. Granted, this is what was pretty well inevitable with the FCC unrestricting the 2.4ghz band.
now there are technologies they never thought of, like interference from this light. I seriously have a problem with any of these 2.4ghz products: i'm not even guaranteed that my video transmitter will work with my phone without interfering.
i'll wait until Ultra Wide Band products become available. 3.1ghz phones are just around the corner. then watch us roll into GPS territory. maybe we should just switch back to carrier pigeons (:
Perhaps it's because I've never used a wireless network in my life for computing, but I'd much rather have low cost lightbulbs myself.
Low cost lighting benefits everyone, rather than the relative few who can and will access wireless networks. I can see the power in wireless, but since most people will never take advantage of this, and you can be environment-friendly in the process, I say go for efficient lighting. As Cringley briefly mentions and then forgets for the rest of the article, it will decrease energy usage and reliance on oil, which will really benefit everyone.
This whole "war on terror" would not likely be happening without our (the US's) incredible appetite for oil. Anything we can do to curb this will be beneficial, and that to me is far more important than being able to get sports scores and news headlines on my Visor.
"I may not have morals, but I have standards."
I want to be able to moderate stories down. And I want karma values for the bozos editing this stuff.
Maybe it's just me, but this is a no brainer. Sure, I'm writing this from the shitter thanks to my 802.11b network. Sure, I like using my laptop anywhere near my apartment. But if these lights are the real deal--prime time or not--I'll gladly move to an 802.11a network if/when they're widely used. Light bulbs waste a tremendous amount of energy nationwide, and if these bulbs can help reduce that, then great! We can only abuse the earth so long. We can wait until after we drop a deuce to check email, or can upgrade to 802.11a if we really can't.
Of course, widespread adoption of the new lights is a huge concern. Look at how energy efficient compact flourecent lights are, and how relatively few are actually used.
Anyone know exactly how much power these lights are supposed to give off? If these are supposed to save power better than current technologies(e.g. florecent) they need to put out 12W. But the claim is that it interfers with 2.4GHz so how much power is going out in that band if the whole thing is only using 12W? It seems unreasonable that 12W falling off at 1/r^2(okay I assume a sphereical bulb) would have enough power to interfer with WiFi .5miles away. So does anyone know the power output(or usage) of these lights and exactly what intensity a WiFi will pick up?
LED's are not cheaper right now if you look at them in terms of lumens per dollar. They are also not very bright. You cannot use LED's as the headlights on your car, for instance. As the prices continue to drop, there will be more and more uses, but the technology needs to develop more high-power, high-output LED's in order to take over the place of incandescent and halogen bulbs.
My other first post is car post.
I find it incredibly hard to believe that one of these low power lights can radiate so much field strength in the 2.4 GHz band that it will knock out wireless networks for a half mile.
These lights are governed by the same standards as WiFi networks with regard to field strength. Namely, FCC Part 15.
These light fixtures would likely be considered "incidental radiators" by FCC Part 15.
An incidental radiator must use "good engineering" practices and must not cause harmful interference to radio services.
It seems to me that wiping out a half mile of wireless networks is harmful.
Just for sake of argument, let's bump these lights up a notch to "unintentional radiators," which means they generate radio energy internally for whatever use but do not by design radiate it into space. In this category, they are limited to 500 microvolts per meter of radiated field strength as measured at 3 meters distance.
This is exactly the same field strength limitation placed on intentional radiators in the 2.4 GHz band.
This means that these lights may only produce as much radio energy as a WiFi base station/client card with a unity gain antenna.
The FCC has also classically ruled against unintentional radiators which cause interference with intentional radiators due to their excessive field strength, regardless of whether they meet the requirements of Part 15 or not.
The FCC normally requests that unintentional radiator manufacturers show good faith by being far below the legal limits permitted in Part 15.
I'm not even going to go into the fact that WiFi is a spread-spectrum system and is very immune to traditional forms of interference. Unless these are spread-spectrum, intentionally radiating low power lights, I don't think we've got much to worry about.
Also, whomever thinks the FCC just doesn't care what goes on in the unlicensed portions of the spectrum is wrong. They certainly don't chase down every Part 15 violation, but they do randomly sample finished products from a variety of manufacturers to determine their compliance.
The manufacturer gets into trouble if these things don't meet Part 15 requirements, so these lights will simply never get off the ground if they interfere as much as it has been said they do.
All opinions presented here aren't mine.
I have a MUCH better question that Lightbulbs vs. WiFI:
What would you prefer? The WB Network or WiFi+Lightbulbs?
Why are the "people" shoved into this tiny band where they have to fight against microwave ovens and friggin lighting systems while bottom of the trash heap networks are given the rest of the spectrum FOR FREE to put crap on the air that provides no value and nobody watches anyway? Shouldn't those airwaves go to something good and useful, and actually help promote society?
"Your superior intellect is no match for our puny weapons!"
Not all of us can reload evry 10 minutes all throught the day. Nor can we all spend hours digging through the archives to find what we may have missed. While I do agree that posting the same story two or even three times in a single day is a clear sign of lazy editing, having a potentially important story (and having my WiFi decimated is pretty serious in my world) repeated every so often lets those who missed it the first time hear about it.
"Your superior intellect is no match for our puny weapons!"
They light longer when powered by batteries though because their intensity doesn't drop off as much as incandescents do as the voltage drops.
LEDs are diodes. They have a constant voltage drop, generally around 1.2 volts. As you increase the supply voltage (through a resistor) you increase the current flowing through the device. It's not really a function of the voltage applied - you get the same effect by changing the resistor value. It's simply I=V/R (current = voltage / resistance), taking into account the voltage drop across the diode.
What's important is the amount of current flowing through the LED.
Not that it matters... in any case LEDs are, by comparison, not all that efficient.
NGWave - Fast Sound Editor for Windows
It's perfectly legal for these lights the "wreck" havoc all over your WiFi networks because the spectrum was set aside for industrial use long before anyone thought about WiFi. Part of the agreement the 802.11b people made with the FCC was that if some application came up in the future that interfered with 802.11b, they would just have to deal with it. I read all this on some site that was linked to from a /. article a few weeks ago. I forget where. Search in the archive for "fusion lighting" or "microwave lighting" or something. Long story short, WiFi was betting that no one would come up with an interfering device, and they did, so WiFi is screwed.
on a related note, where the hell did this WiFi acronym come from and why does it stand for Wireless Fidelity? My dad mentioned was reading a news paper and he says "Son have you heard of this WiFi or Wireless Fidelety?" and i laughed in his face and made fun of him for getting suckerd by an ignorant news reporter who was just assuming what WiFi stood for (HiFi means High Fidelity, so WiFi must mean Wireless Fidelity) The logic seemed assinine to me at the time, even though I didn't know what the Fi stood for. Turns out _I_ was the rube. Does anyone have any idea what Fidelity has to do with computer networking? Isn't fidelity sort of implied when you're dealing with digital transmission? Am I getting too worked up over a stupid marketing ploy?