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WiFi, Light Bulbs, And The FCC 247

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.
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WiFi, Light Bulbs, And The FCC

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  • by The_Deacon ( 137827 ) on Thursday June 13, 2002 @02:08AM (#3691952)
    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.
    • by Animats ( 122034 ) on Thursday June 13, 2002 @02:24AM (#3691997) Homepage

      I want to be able to moderate stories down. And I want karma values for the bozos editing this stuff.

    • excoos when askeng. Can tell anebode what is the famous WiFi? Reading the slashdot but do now not understend. Friends? Plaese help?

      Excoos for speling
    • Hemos pulled a ChrisD. What, somebody had to say it!
    • It's not so bad... (Score:3, Insightful)

      by gnovos ( 447128 )
      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.
  • Uh, oh... (Score:3, Funny)

    by TheDanish ( 576008 ) on Thursday June 13, 2002 @02:08AM (#3691954) Journal
    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.
  • 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.
  • Wot about LED's? (Score:2, Redundant)

    by marcushnk ( 90744 )
    Why can't the world just grab a clue and use LED's instead... MUCH cheaper, MUCH tougher and MUCH better.
    • Re:Wot about LED's? (Score:3, Informative)

      by Cryptnotic ( 154382 )
      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.

    • Poor spectrum (Score:3, Informative)

      by alienmole ( 15522 )
      You wouldn't want your house to be lit by current LED technology. They have a much narrower spectrum of light than any commonly used bulb technology - sort of the opposite of the "natural light" bulbs that some companies sell.

    • White leds are just afew yesars old, and are pretty darn expensive. If this RF excitation lamp thing is cheap and reliable as it can be, it will be more effective..

      Not that I really want more EMI all around me into my brains. WiFi or what ever..

    • LED's don't actually use (much) less energy as compared to an incandescent bulb. They light longer when powered by batteries though because their intensity doesn't drop off as much as incandescents do as the voltage drops.

      The most efficient light source (except for exotics) is still the flourescent tube.

      Let me see if I can dig up a reference...

      Ah, this should do:

      http://www.resurgentsoftware.com/gpetrie/The_Per fe ct_LED_Light.pdf

      Scroll down to page five. Note that the above link is a .pdf file. Also, I don't seem to be able to get the "Perfe" and the "ct" to stick together so you may need to cut and paste. Sorry. I don't know if it is me, or Mozilla that is doing it.... No, IE is doing it too. I guess I'm just unclueful.
      • They light longer when powered by batteries though because their intensity doesn't drop off as much as incandescents do as the voltage drops.

        According to that you could run them on less voltage for not that much less light then? And hence be more efficient...
      • 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.
    • Why can't the world just grab a clue and use LED's instead...

      Um, stopped at a traffic light lately?

      - A.P.
  • by Anonymous Coward
    While I agree that energy conservation is an important factor, consumption from light bulbs has to be balanced with all the rest of the devices in a home. What about TVs, or washer/dryers, or dishwashers? Or all of the industrial consumers? All those consume far more energy than regular residential light bulbs. Heck, we already have fluorescent bulbs for those who want to save. These light bulbs sound like a feel-good measure for those interested in saving the environment. Save the exchange of information FIRST.
  • Cell phones, laptops and PDAs with light switches?
    I would pay to see that!
  • i like hallogen instead, screw power companies , make some fusion shit, then give it to us for free,
  • by NewtonsLaw ( 409638 ) on Thursday June 13, 2002 @02:12AM (#3691969)
    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.

    • Speaking from experience sputtered coatings would add a couple of cents to the _manufacture_ of light bulbs, minimum. Probably close to a nickel - extrapolate this out to retail pricing and your probably talking about an increase of .25 to .50 cents. A substantial difference for the lightbulb world.

      Of course my odea has always been to sell a stereo cabinet with "a new improved IR reflective coating that improves playback on your CD's" and doesn't allow one to use the remote. I wonder how many I could sell before the first return?
      • probably talking about an increase of .25 to .50 cents. A substantial difference for the lightbulb world.

        Given that currently small flourescent bulbs (drop-in replacements for incandescents), which use less than a fifth of the power of incandescents cost about $10 (australian), 50c isn't much, really. I can't imagine these new bulbs will be particularly cheaper. at least nowhere near the 50c or so for incandescents.

    • by CaptnMArk ( 9003 ) on Thursday June 13, 2002 @02:33AM (#3692023)
      Imagine the power the light bulb could save if it didn't radiate useless 2.4GHz interference in a half mile radius.
    • And what will happen if somebody accidentally peels or scrubs this coating off? You'd end up with a huge interference just because grandpa ditched the bulb and all the people in the office nearby 'd be really pissed :-)

      rinse, repeat...

      Maybe one could insert some kind of EM-shielding fluid into the bulb and shake it 'round until it dries...
  • ...like the fushions on my couch?
  • I've seen this suggestion before... But I want to state again that I think Cringely deserves his own Section... I look forward to reading his article every week. It is always topical and insightful (even funny at times)... Also, everyone should read about the tragic death of his son here [pbs.org]. If you have children you know how scary SIDs is. If you have the time, please help with his cause.
  • by unsinged int ( 561600 ) on Thursday June 13, 2002 @02:19AM (#3691982)
    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.....

  • by jukal ( 523582 ) on Thursday June 13, 2002 @02:19AM (#3691984) Journal
    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.

    • I'd think that at some point wireless will be ubiquitous like cell bands and you won't need to broadcast your own.. isn't that what you meant by 'success story'.

      Not broadcasting your own means much less interference AFAIK. This will happen soonest in tightly populated areas.. looked to Japan to be the first to have public access WiFI.

      Course i have to ask how does WiFI scale to N users per square mile/km?

    • You must have missed the story, a few weeks ago, where the FCC invited an MIT proffesor to tell them that spred specturm would eliminate the spectrum scarcity and the FCC's mission, to regulate that scarce public comodity, would be over. The FCC may wish to crush the technology before it crushes them. They did the same thing to amature TV broadcasts as well. You know, 69 empty channles on the TV? Ever wonder why no one was broadcasting on them or over ham radio? So sad, too bad.

      So what do you want? Unlimited cheap personal freedom of press and perfect universal news retreival or an alternate light bulb? I see fine at night right now, thank you, but I have to pay $65/month for cable. It would be just fine for the FCC to let these folks blot out the 2.4 GHz band, so long as they give the rest of the specturm back to the people.

  • by beckett ( 27524 ) on Thursday June 13, 2002 @02:21AM (#3691989) Homepage Journal
    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 [gcn.com] 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 (:
  • Another thing producing radiation at 2.4GHZ. I wonder how many things have to be around before I start getting cancer. My HAM radio book says I should try to limit individuals exposure to radiation at frequencies this high up in the spectrum. Now it seems that every one potentionally is going to be producing radiation at this range, although at a lower total output level. However, if I have 400 people around me producing 1 watt, I could end up with getting 0 or 1000's of watts of energy at this frequency depending on where I'm standing. Perhaps I should go and purchase a Tempest suit or make my own.
    • ..my monitor.. my cell phone.. my brain hurtz and I can't do math.. numbers escape me..

      Dude, do not tie you panties in a knot. 400 people around you will need to shove their wi-fi up your ass and wrap you in tin foil for you to absorb all that energy. Not that it is entirely impossible, it's for you to tell, but for most of us - highly unlikely usage pattern.

      Some data HERE [mcw.edu]

  • by krmt ( 91422 ) <therefrmhere@yaho o . com> on Thursday June 13, 2002 @02:23AM (#3691995) Homepage
    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.
    • You said it.

      It really irks me to see countries like Germany turning away from clean energy like nuclear. Until fusion comes around, nuclear is the best choice we have for cheap and abundant power generation.
      • Wow, do you really think nuclear power to be *clean* ?? There is no such thing as clean power supply. Don't judge power technology by "what could be done" . Judge it it by "what actually has been done".
    • Do you drive? (Score:2, Flamebait)

      by wirefarm ( 18470 )
      How much oil and gas do people consume getting to and from work?
      Wireless networks will further allow people to telecommute, reducing dependancy on oil. Sure, right now, most people are a few meters away from the access point, but creative people are building long-range networks using these things, within the boundaries of the current laws, using well-engineered antennas and low-power transmitters.

      Look at those super-efficient flourescent bulbs that have been available for years. People just don't use them, probably because they cost more than the super-cheap incandescants that most people are used to.

      On a personal level, I've spent a couple hundred dollars building my wireless network at home. Am I supposed to just toss that equipment into a landfill because my neighbor wants to save a few cents and feel that he is being 'green'?

      What about the regulations that the FCC has on RF noise-emitting devices - don't they apply, even though the spectrum is free?

      • Re:Do you drive? (Score:2, Insightful)

        by Xugumad ( 39311 )

        I'd just like to back up the original poster, and add no, I don't drive, I walk to work. Every day. Oh, and I use the flourescent bulbs.

        I understand your annoyance about the fact that the wireless network and bulbs work on the same frequency. I'd use the bulbs without hesitation, if it only affected my house...

        Oh, and while we're on the subject of energy saving bulbs, when was the last time anyone here thought about energy consumption of a computer they put together? How about all those who boast about uptimes - are you really using it continuously? Imagine the waste of electricity from that!

        • (I cycle to work myself, but only use flourescents in the summer, when I start to notice that the halogens are making it warmer in my place. Awful things, those...)

          About the server, yes, I am one of those 'uptime' boasters - (294 days - Woohoo.) but I specifically chose a machine with pretty low power consumption, plus, where I live, the power comes from nuclear, not oil or coal.

          Still, if my neighbor's porch light starts to interfere with my por^H^H^H downloading, I'm going to buy an air rifle...

      • How much oil and gas do people consume getting to and from work? Wireless networks will further allow people to telecommute, reducing dependancy on oil.
        Would you like to tell me how I'm going to sell clothing at my retail job from home? Or perhaps how I'm going to centrifuge my DNA for my research at home?

        Telecommuting is great for some people, but most people actually need to physically be somewhere to get work done, and that includes me.

        And incidentally, I take the bus to work. Yes, it burns oil and gas, but public transportation goes a long way towards helping the problem. Here in Los Angeles, there is very little public transportation for various reasons (one is that we have a subway system that is completely filled with concrete, thank you corporate America!) and this is another problem.

        While you might be enjoying wireless in your home for various reasons, I can guarantee you that less than 1% of the people in my neighborhood would even consider such a thing if they knew it existed, given their meager budgets. Most people aren't going to use wireless, but efficient lightbulbs will help these people. The fluorescent lights don't have the natural light feel of incandescents, and if these new bulbs provide that then I'd be surprised if they weren't used.

        Oh, and Cringley covers the part about FCC regulations in his article.
        • You probably can't do *your* work from home, but if you are my neighbor using these lights, you may be denying me the ability to telecommute.

          I still think that if you introduce a technology that uses a shared public resource such as public bandwidth, you have a responsibility to not trash the resource for others. (Kind of like not organizing a football game in an area of a park where people happen to be having picnics.) Sure, it may be legal, but it's rude.

          I'd guess also, that if your neighbors *do* get 'wired' in the next few years, the best way would be using this technology. Wireless NICs will be incredibly cheap in the next few years, while retrofitting apartment buildings with LAN cable will never be.

          Do you think these bulbs would be allowed if they interfered at all with television signals, no matter how well they conserve energy? Doubtful.

          • You make some good points, but in reality these lights will never prevent you from telecommuting. A DSL or Cable line will allow you to do the same thing, although it will cost a bit. There's nothing really new in wireless, just mobility, and if you're telecommuting, there's no reason for you to have to be able to take your work with you to the park or something.

            And for those people who might need that kind of instant access (reporters are one example I can think of) cellular modems would allow quick submission of data.

            As for wiring whole buildings, you're right about that, although many people only have one computer (if that) so they don't need to wire their entire place, they can simply get their connection via their pre-existing phone or cable jack. If they need a LAN, wireless is great, but most people don't need that in the slightest.

            I agree though, that these lights shouldn't trash the spectrum. Someone mentioned engineering them using shielding the same way LCD's are shielded, so hopefully something to that effect would be in place. My original post was more hypothetical than anything, a sort of "what do you value more?" thing. I'd easily sacrifice wireless to save on my energy bill, and I'd imagine a lot of other people would do the same. Hopefully we'll never actually have to make that sort of choice, if they can figure out how to properly shield these bulbs.
    • This whole "war on terror" would not likely be happening without our (the US's) incredible appetite for oil.

      This is irrelevant to the discussion for two reasons:

      Point 1: Oil isn't used to generate all that much electricity in the US. Most US electrical power comes from Coal, Natural Gas, and Nuclear. So light bulbs don't mean didly in the fight against terror. Those 8MPG SUVs, on the other hand...

      Point 2: The US doesn't get terribly much oil from the Middle East. Most of the US' oil comes from the US (last time I checked the numbers, we were still the #2 producer of oil on the planet, but Russia's output has gone up quite a lot recently), Venezuela, and Mexico. Oil from Arab countries is less than 20% of US consumption.

      It's the Japanese and Europeans who are proping up the dictators in the Middle East, which explains their reluctance to do anything but kowtow to these tyrants.


  • Isn't it simple? (Score:3, Insightful)

    by An IPv6 obsessed guy ( 545330 ) <slashdot@radioactivedata.org> on Thursday June 13, 2002 @02:24AM (#3691999) Homepage
    So what would you prefer?

    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.

  • Since the bulb is not even on the market yet, what is to stop the company from improving the design at the last minute? And where did the author of the article get this information to begin with? It seems kind of shaky.

    It seems to me that if this *really* poses a problem that it will be noticed and dealt with quickly, assuming that a sufficent number of people with high speed wireless live in an area with one of these lightbulbs being used...

    • Since the bulb is not even on the market yet, what is to stop the company from improving the design at the last minute? And where did the author of the article get this information to begin with? It seems kind of shaky.

      Well, I actually think that this 'bulb' is already on the market for at least 10 years.
      It is very common in Europe to replace normal light bulbs with low power bulbs based on fluorescent TL.
      Those 'bulbs' use 8 times less energy than normal bulbs and a ten times longer life time.
      Only disadvantage is, that can interfere with wireless equipment.
      But I never had any problems with WiFi.
  • Too much power? (Score:5, Interesting)

    by forand ( 530402 ) on Thursday June 13, 2002 @02:30AM (#3692016) Homepage
    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?
    • Re:Too much power? (Score:3, Informative)

      by ColaMan ( 37550 )
      Don't Wi-Fi cards output in the 20-100 milliwatt range usually? I'd presume that these lights only produce a minor amount of 2.4ghz of output or the FCC'd be all over them. The 2.4Ghz band *is* regulated still - there are limits on power output etc.

      Anyway, it all depends on how it is distributed across the 2.4Ghz spectrum - I presume it's peaked being RF excitation, which normally means you're aiming for a narrow energy state in your gas. So, a single 500khz-wide peak with all output power going into it ain't going to hurt too much.

      But the other extreme is also true - a few watts of energy, dispersed across the entire 2.4Ghz range will just wind up being a low-level noise.

    • Re:Too much power? (Score:5, Informative)

      by wowbagger ( 69688 ) on Thursday June 13, 2002 @07:59AM (#3692709) Homepage Journal
      It takes very little signal power to disrupt radio communications.

      In radio, you measure signal power in dBm (decibels referenced to 1 mW). A typical narrowband FM receiver, like a cell phone, has a sensitivity of about -120 dBm - in other words, if the phone is getting -120 dBm at the antenna port it will just barely work. -120 dBm is one 10E-12 of 1 milliwatt - or one thousandth of a picowatt.

      For a wireless LAN card, I think they usually want to see about -76 dBm for a good link - that's 10E-7.6 of a milliwatt being received, or about a twentieth of a nanowatt.

      Let's say the lamp is a 5 watt lamp (and from what I understand most of these lights are more like 100 watts excitation energy - these aren't your floor lamp!) Let's say the lamp leaks .01% of its power - that would be half a milliwatt. Assume the leak is an isotropic radiator (radiates equally in all directions). So you have .5 mW (= -6 dBm) into a 0 dBi radiating antenna. Your wireless card is about +30 dBm into a +3dBi antenna - so you would have -6 dBm interference vs. +33 dBm ERP for the wireless transmitter, assuming they were both at the same place. That wouldn't be a problem.

      Now, if the lamp is anything like the microwave pumped lamps I used to work with, you are talking about 500 watts or more of excitation energy - that's +20 dB. If the lamp leaks 1% of its signal (still small enough to have no real effect on the light output) that would be another +20 dB of leakage. You now have taken the lamp from -6 dBm ERP to +34 dBm - and you are now just as "loud" as the network card.

      Also, these lamps are pumped by magnetron tubes, same as your microwave oven. These aren't nice, single-frequency sources - they spatter over a fair chunk of the band. So you cannot modulate them and use them as network nodes, and you cannot easily skip over the frequencies they use - they don't just impair one channel of a frequency hopping system, the impair many channels.

      However, I have to wonder how the efficency of these lamps compares to the new LEDs on the market - it may be a moot point.
    • It seems unreasonable that 12W falling off at 1/r^2 would have enough power to interfer with WiFi .5miles away.

      People keep forgetting the energy SCALE here. WiFi communications have very low power levels. Area lighting uses energy in bulk. Even a fraction of bulk energy is still a lot.

      So does anyone know the power output(or usage) of these lights

      I can't find any figures on these lights. Lets be generous and assume they only leak a single watt as interference. Now assume a *tiny* gas station with just 2 double sided pumps, 2 bulbs per side per pump, 4 for the building exterior, 4 for the interior. And oh yeah, one for the sign. 17 bulbs, 17 watts RF interference. (17 is a joke, I know a local megastation that must exceed 100, not to mention supermarkets).

      and exactly what intensity a WiFi will pick up?

      WiFi typically runs in the 30-70 milliwatt range with a 100 mW limit. Lets assume you're running the max, 100 mW. To maintain a reliable connection Cisco quotes a minimum signal/noise ratio of 20 decibels, or 100 to 1. Further assume said tiny gas staion is the only background noise.

      The equation is therefore:
      1/r^2 = 100mW signal/17W noise/20db signal-to-noise
      1/r^2 = .1 / 17 / 100 = 1/17000
      r = 130.4 (the interference range must be at least 130.4 times the signal range)

      interfer with WiFi .5miles away

      One tiny gas station .5 miles away divided 130.4 leaves a WiFi range of 20 feet.

      I have 2 mid sized gas stations and a supermarket about 1/4 mile from my house. Using less generous assumptions my WiFi range wouldn't be enough for a wireless mouse or keyboard, not to mention Bluetooth which only uses 10 mW and yeilds a range I can hold in my hand.

  • 1. Why are Cringly's articles automatically turned into /. posts.

    2. Did the submitter read the article? The gist of the story was that 802.11b would work just fine with the new, RF-noisy lights.

    3. Yes, a more insightful webpage & technically detailed website was listed on slashdot just a couple of weeks ago.

  • Let me get this straight, 802.11 and cell phones are very limited in power emission to (sensibly) keep our microwave exposure to safe levels, but now these light bulbs are going to be everywhere that emit enough microwaves to drown out wireless data stuff? Will the light bulbs give us cancer or sterilize us? That seems like a much more pressing question than the energy-savings vs. broadband access tradeoff.
  • May 8, '02: Hemos posted New Lighting Technique to Wipe Out WIFI?" [slashdot.org]

    Mr Cringley has cribbed a bit belatedly :)

  • ....but its too irresistable
    To quote a famous rapper, modified for the slashdot masses

    So the FCC won't let me be
    Or let me be me so let me see
    They tried to shut me down on 802.11b
  • Many people don't realize just how much power light bulbs consume. To borrow some statistics (source [fireshui.com]): 25% of US energy consumption and 10% of the average residential energy bill comes from lighting. Light bulbs are horribly inefficient - 90% of the electricity they suck up is wasted as heat. So from an infrastructure standpoint, a cheap energy-efficient bulb can make a huge economic and environmental difference.
    • Make gaz cheap - people will drive SUV. Make lighting efficient -- they will light up more.

      Just get us fusion power.

    • To borrow some statistics (source [fireshui.com]): 25% of US energy consumption and 10% of the average residential energy bill comes from lighting. Light bulbs are horribly inefficient - 90% of the electricity they suck up is wasted as heat. So from an infrastructure standpoint, a cheap energy-efficient bulb can make a huge economic and environmental difference.

      It's not quite that simple. If the building needs heating anyway then the heat isn't really waste. It becomes waste heat where the building needs cooling, then not only is that energy wasted, but also energy can need to be expended on removing the heat.
      • If the building needs heating anyway then the heat isn't really waste.

        No, but the energy used by the light bulbs and dissipated as heat is probably more than the energy that would be consumed by your central heating unit for the same amount of heat, since the heating unit is designed to produce heat and the bulb isn't. So it's still likely that you would save energy by using CFL lighting and having to run the heat pump a tiny bit more. Even if it's a break-even or a slight loss, you will make up for it when it gets warm again, unless you live somewhere where you never need cooling.
        • If the building needs heating anyway then the heat isn't really waste.
          No, but the energy used by the light bulbs and dissipated as heat is probably more than the energy that would be consumed by your central heating unit for the same amount of heat, since the heating unit is designed to produce heat and the bulb isn't.

          It is impossible to create or destroy energy - 'wasted' energy always ends up as heat. So if you need the heat then it really doesn't matter that your electrical devices are inefficient - they're perfectly efficient at producing heat! If and when you don't need the heat, or the devices are producing heat in the wrong places, then I agree that you would be better off making them more efficient. Of course we should consider the energy cost of manufacturing new hardware, too.

          • Yeah, I know this. I just didn't state my meaning clearly enough in my post. The problem with the heat generated by light bulbs isn't that they aren't efficient producing heat, it's that the heat they produce usually isn't where it needs to be. Lights are typically at or above the positions of people in the rooms, and the hot air rises, so they don't do as good a job of warming the air around the occupants as a well-designed heating system.
      • Worst case, if the building needs heating and the light bulb isn't providing it, you run an electric heater, which will consume no more power than that saved by the new lightbulb to produce the same amount of heat as would have been produced by the old lightbulb.

        However, by separating the functions you now have the flexibility to provide heat from other sources that may be more economical, such as natural gas, or (in some cases) a heat pump.

        And if you ever need cooling, the new lightbulb obviously wins, since you don't have to simultaneously pay to both heat the room with the light bulb and cool it with an air conditioner.

        I doubt that there are many buildings that need heating when there is cold weather, and for which the lighting is sufficient to provide that heating year-round. So most buildings that ever need heating already have some other provision for it, and don't need it from the lighting.

  • i don't have links but i thought someone else set up networking based on the flickering of neon bulbs... maybe a fusion light bulb network would run faster than the 802.11 it is destroying? and at 1/2 mile link a pop they might be cost effective... a few bulbs in every building!
  • FCC regulations (Score:2, Interesting)

    by panurge ( 573432 )
    Doesn't the FCC have something to say about this? The European EMC Directive covers the emission spectrum from DC to the Big Bang frequency, and I remember well getting all the technical papers as the conventional fluorescent manufacturers faced up to the fact they were going to have to redesign their ballasts and ignitors. Even if this particular bit of spectrum is unregulated, what about harmonics? Surely they would be up there in the key shortwave radar bands, raising the noise floor?

    The EMC directive: you're allowed to radiate gibberish, brain-dead stupidity, pornography etc. but NOT NOISE

  • Savings? (Score:1, Insightful)

    by BrokenHalo ( 565198 )
    ...or low cost light bulbs all around the country to save more and more on electricity?

    Who believes we'll save on electricity? OK, I might be a cynic, but experience tells me that if everybody started using low-power light bulbs, the power companies would just hike the price per kW-hour.

  • I would complain about this "story", but I'm getting slashdot for free (or at least, for the price of ignoring a few adds).
  • I want Wireless Light Bulbs OR Light-Up Wireless rays. Either will fit into my plans of world dumbnation!
  • How the heck are you supposed to run a network at all if there is severe interference in the way of the information ?

    Is it really true that the US patent office is dumb enough to not even do any safety checking procedures at all ?

    I thought the one-button online click was pretty bad, but anyone who doesn't even bother to go through all the safety steps involved in the counter-checking has definately wasted too much time sleeping in the office.

    I'm off to have tea and sleep it off now.
  • 5 Years to go... (Score:2, Insightful)

    by Ma$$acre ( 537893 )
    Watch out! A technology that is 5 years away will probably seriously impact a standard that, although in heavy use today, will be superceded in a couple of years.

    Now they not only tell us what vaporware is coming, but what other vaporware might impact it!

    Someone call the Police and file a WGAS Report.

    PS. If there was even a choice to be made it would be for the Lights. Reduction in power consumption is good for everyone but Oil companies and Opec.
  • What nonsense. (Score:5, Insightful)

    by AlphaOne ( 209575 ) on Thursday June 13, 2002 @03:18AM (#3692136)
    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.
    • You're so wrong. These lights are governed by Part 18, ISM. They do not have be concerned about interference as long as they conform to the Part 18 rules, which are much broader than Part 15.

      Part 18 governs industrial, scientific, and medical devices that don't communicate data, but rather emit radiation as a direct purpose of their utility: microwave offices, industrial sealers, etc.
      • Light bulbs do NOT emit microwave radiation as "part of their utility," because the radiated microwave energy has nothing to do with their intended purpose, which is producing light. The fact that they use microwave energy internally to produce the light is a means, not an end.

        In your other examples, emitted microwave radiation is the desired function, rather than incidental.

      • Re:What nonsense. (Score:3, Interesting)

        by AlphaOne ( 209575 )
        To be honest, I hadn't even considered Part 18! So few devices qualify for Part 18 I don't really even think about it.

        These lights could very well be Part 18, although RF lighting isn't mentioned specifically in the section.

        I don't know the specifics of the design of these lights, so it's really hard to say. Shooting RF energy through a glass tube to excite a gas doesn't seem like it should radiate so much energy as to wipe out wireless networks for half a mile in any direction.

        Personally, I'd have reservations about sitting under such lighting all day if it did!

        Part 18 devices are limited to 2.4 GHz - 2.5 GHz, which unfortunately wipes out the entire Part 15 subband. They're also authorized a much higher field strength... at less than 500 watts (which we can assume these lights will be) it's 25 microvolts per meter measured at 300 meters.

        However, I still don't see these fixtures being a problem for reasons aside from the Part 15/18 argument.

        Properly designed, these lights should only emit spurious emissions at very low power and at specific frequencies and harmonics within the ISM band. Spread spectrum devices should see around this interference. Perhaps the range or speed would be a little more limited, it shouldn't be a huge impact unless your base station is sitting right under one of these lights (which is possible).

        Also, you must consider market pressures. If they hope to sell these devices to businesses (the largest consumer of flourescent light bulbs) they simply have to consider wireless networks. By the time these fixtures are available on the market, wireless networking will only be more common.

        No enterprise is going to purchase lighting devices that wipe out their wireless infrastructure.
  • Better question... (Score:3, Insightful)

    by gnovos ( 447128 ) <gnovosNO@SPAMchipped.net> on Thursday June 13, 2002 @03:24AM (#3692145) Homepage Journal
    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?
    • I agree wholeheartedly with this opinion... please mod up.

      Kevin here also seems to agree... calling our airwaves a 'precious natural resource'.


      "Spectrum management decisions are always complex and challenging," said Kevin J. Martin, another FCC commissioner. "In an environment where the amount of unencumbered spectrum is decreasing while demand continues to grow, it is even more critical we make interference and sharing decisions that do not waste this precious natural resource."
  • I got Phillips light bulbs all over my house already so it's wireless LAN for me.
  • We choose the wireless networks. They're more important to communication, and overall, our economy.

    Plus, let's go ahead and use up all the electricity we can. Let our kids deal with the problem. Those bastards deserve it.
  • Fushion Lightning should join the Wireless Alliance [slashdot.org].

    Each of those little light bulbs should come with an RJ-45 socket.

    Regards, Ralph.

  • Please read the article before you guys get all "the story sucks" -- XM radio uses this frequency band as well;

    WiFi i can't care less -- 802.11a is already making headways, by the time any kind of remotely user base of the light bulbs are established, i would have (as i assume a large portion of the rest of y'all) moved onto 5.8Ghz; or drop the speed down to 2Mbps; -- DSL is only 1.5 anyway -- and if i was really gonna move that much file -- i would just pull a cable temporarily or start the transfer and get some coffee -- either way i do not see it being a big problem for WiFi.

    on the other hand, i don't see the feasibility of XM radios getting an upgrade... so if these bulbs do get popular, it means XM would work everywhere except the cities. ha!

    so if they are really that troublesome, we will be seeing the company getting squashed in no time; there are too much $$ at stake for XM;
  • Light dimmers using varacs have been around for a long time, and they generate huge amounts of RFI--as an SWLer I hate them with a passion. Does anyone know whether the hash they emit extends up into the band used for WiFi?
  • We need at least two frequencies dedicated to public TCP/IP over wireless. One in the high bandwidth, medium-low distance NLOS range (such as 2.4 Ghz), and one in the low bandwidth, long distance NLOS range (such as 154.6 Mhz).
  • One wreaks [dictionary.com] havoc, not wrecks havoc.

    Are basic english skills too much to ask for? And I'm not whining about people who speak English as a second language. I'm talking about the english-is-my-first-language-but-i'm-too-fucking-i ncompetent-to-speak/write-it-correctly crowd.

Never tell people how to do things. Tell them WHAT to do and they will surprise you with their ingenuity. -- Gen. George S. Patton, Jr.