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New Lighting Technology To Wipe Out Wi-Fi Access?
Richard Evans writes "Focus on Broadband Wireless Internet Access has an article
[cached by google ]
on the potentially catastrophic interference to Communications Users Of The 2.4 GHz Band e.g. Wi-Fi, DECT and Bluetooth by a new lighting technology called RF Lighting."
They finally learn, and put a link to the Google Cache, IN THE FUCKING ARTICLE???? I'm so impressed.
I thought regular fluorescent lighting already fucked shit up, since its not really a steady light (like incandescent) but really flickers on and off REALLY fast. Some guy thought a cool way to basicly broadcast info from these lights was by slightyly altering the timing to transmit data....
Who needs RF lighting anyway? I'd rather have a wireless laptop/pda.
So RF lighting is just normal lighting at a different frequency. A frequency that humans can't even see! Trying to listen to the radio or use wireless networking in the presence of RF lighting would be like trying to watch TV with a spotlight in your face.
Karma: Good (despite my invention of the Karma: sig)
The website it cites: Link is *still* blank at least a year after it was cited.
The article also goes into very little detail as to *why* this new lighting technology will be either popular nor necessary. It's vaguely referred to as "very high efficiency."
Summary: Call us when you have real news.
This article says that Sirius and XM Radio will be effected. That's really bad. Part of the reason it's worth paying for is because of the sound quality...having this happen in it's relative infancy could be realllly bad. I wonder if there's a way to shield these lights...like some sort of compound mixed into/spread on the glass that reduces the RFI. Either that or, as a geek community, we should just hope that this idea doesn't take off!
Man with those lights I can grow weed, light my pit of an appartment, completely screw the wireless network the guy next door who has to play mp3's at the highest possible bass level at 3 in the AM!
Pro's:
Heat, grows good herb, and kills the wireless network.
Con's:
ahhh, shit I forgot...pass that would ya!
Neck_of_the_Woods
#/usr/local/surf/glassy/overhead
I don't know what this lighting is, although I suspect it may be "sulfur" lighting.
However if it's going to trash your wireless network then the chances are good that you won't even install it in the first place. That takes care of homes and _probably_ office buildings.
The problem is going to be "public areas" where the lighting is installed to save on electricity costs, and then interferes with ISP's as the article stated. This of course assumes that the lighting is so much more efficient than sodium or mercury vapor that it's worth the expense of installing it in the first place.
And it's going to take years.
Far from an ELE.
Absolute statements are never true
does this mean that I have to re-wire all of my "wi-fi" devices?
worse, does this mean that I'll have to start referring to them as "wi-wi"?
To prevent interference, RF lights should simply practice exponential backoff for colision avoidance like everyone else in the 2.4GHz range. What's more, the lights would then become an effective network load monitor.
--Ben
Couldn't the RF Light manufacturer just shield the light fixtures e.g. a Microwave Oven?
In fact, I would think the FCC would make them, if they had an output over a certain threshold.
'He was a dreamer, a thinker, a speculative philosopher... or, as his wife would have it, an idiot.' - Douglas Adams
I'm not a big supporter of the FCC (who frequently overstep their bounds), but this is exactly why parts of the radio spectrum need to be regulated. The entire reason that the FCC keeps such tight control is so that companies that invest in radio equipment have some assurance that the guy next door won't simply drown out his signal with more powerful equipment.
But then again, every time my boss walks by with his cell phone, my monitors fuzz out and my speakers make strange noises from whatever signals the cell phone is emitting...
Travis
http://www.fusionlighting.com/technology.htm
The article makes a big point out of the collision between the frequency spectrums, however I personally am interested to find out more about the lighting technology that is "high efficiency and RF based". It seems the article kind of missed that explanation, and I can't find much information on it. The lighting's website is down that is referred to, and as far as I know this could be a "made up" problem (by this dude who wrote the article) primarily because it's only a problem if the lighting technology catches on.
Are the light technology elements mounted in the ceilings like conventional flourescent lights or does it use some kind of a central light-source idea. If it's high-brightness and high-efficiency anyway, the light source could be placed at a central (shielded) location and fiber optics used to distribute the light.
I'm all for new light technologies, although often flourescent lights are pretty good, there is still a lot of room for improvement. (Time delay to full brightness, hazardous materials, cheap ballasts that buzz, bad fluorescent tubes that put off funny-colored lights) But interfering with wireless spectrums (even unlicensed ones) seems like a bad idea in general... the amount of noise in any spectrum is becoming a serious concern for the design of "robust" wireless technologies.
__ No registration required to read this message. They did it in the Matrix.
Read the article:
Eventually the FCC decided to offer a Faustian bargain: Industry could use the existing ISM spectrum if they adhered to certain technical limitations with no expectation of protection.
In other words, as long as you stay within the 2.4 GHz spectrum, you can do what ever you want, as long as you didn't expect to be protected from interference from other devices.
Bluetooth and 802.11B have already violently clashed in this space already. I have seen it myself - with a 802.11B card in one PCMCIA slot, as soon as I turn on a bluetooth card in the other slot, my average ping time on the 802.11B goes up considerably.
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Why get all in a lather about RF lighting?
If solid state lighting takes off we'll get great efficiency and no 2.4 GHz spectrum pollution.
"Provided by the management for your protection."
This article is utter garbage!!!
The first link (off-site) from the article referred to, in fact the makor of said "RF-Lightning-Craptacular VC-Money Whoring" company has a "our website is under construction" on it.
C'mon people - stop posting obvious flamebait articles at the highest level. This was a freakin waste of everyone's time.
The company I used to work for did the very first large scale (non-test) installation of their lighting products in the US. It sounded like an awesome product. It would provide MORE light for LESS power with LESS maintenance.
:)
We installed a HUGE area with this stuff (took many months to do the install). A year later we ended up yanking every bit of it out. Why? Well, there were SEVERAL technical problems with these things that they hadn't worked out. The short version of how they work is that they irradiate a glove with some sulfur in it with microwaves and turn it into a glowing plasma. Well, that stuff is a bit hot, so you have to continuously rotate the 'bulb' This rotational part breaks, so the light breaks.. the reflectors can't stand the heat, etc.
so don't worry.. they are in bankruptcy...
This looks like a niche product. It's not even clear that Fusion Lighting is still in business. Their web site is essentially defunct. Their web site used to have some nice pictures of glass bulbs and more info, but now, it's just a starter page.
It seems unlikely to me that these things will be all that catastrophic in their effects. To be power-efficeint light sources, each bulb will have limited power with which to generate interference. To be power-efficient enough to make a difference in this market, this technology should probably consume <10 watts for the equivalent of a 60-watt light bulb. Considering that most of that energy will be going into visible light, it can't be a very strong signal source. Even in large installations like gas stations, where many such small sources would exist, the effect should fall off quickly. Don't use them in your home, and your wireless LAN should be safe.
The reason the satelite radio providers are running scared is that these things are mainly slated for use in street lights. Since cars tend to drive under street lights, and car users are the big market for satelite radio, someone's business model will have to give. Even small intereference feilds can be a big problem if they interupt your line of sight, particularly with high frequencies.
The article is rather light on details about how exactly the lights are going to interfere.
2.4ghz is special in that its the resonance frequency of the water molecule. That's why microwave ovens operate at that frequency: vibration = heat.
So how exactly are these folks going to sell a product which emits high wattages at that frequency? Sitting under one would be like sticking your head in a microwave.
Answer: They're not stupid enough to sell a product that is like sticking your head in a microwave. Some critical facts are missing here.
The wireless stuff isn't particularly dangerous since its emitting at such a low power: well under 1 watt where the typical microwave emits at up to 1000 watts. And the spread spectrum technology does a good enough job of ignoring noise that the technology works despite the leakage from those ovens. If the wireless stuff does OK in the presence of leakage from 1000 watt Microwave Ovens, it'll do fine in the presence of other safe 2.4ghz devices.
Moderating "-1, Disagree" is simple censorship. Have the guts to post your opinion.
The really stupid part about that is eventually 5 GHz will have the exact same problem.
Read the article more carefully. It states a section in the 5 GHz range reserved for communication devices only.
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- - You can't take something off the Internet! That's like trying to take pee out of a swimming pool.
When I was a kid, I had a set of encyclopedias of the sort that were parodied in Science Made Stupid a wonderful book if you don't have it.
Anyway, one illustration that stuck with me was a drawing of a man at home at a desk, reading a book. In the background are baseboard radiators with little squiggly lines coming out of them. The caption reads "In the future we will save energy in home heating by using microwave radiation to heat, people but not the furniture." This article on microwave lighting reminds me a little of that picture.
Yeah, those were the promises. I really wish it would have worked out better. a few details of the problems:
#1 - the BULBS might last 11.4 years, but the magnetron that shoots the microwaves into the bulb, and the motor that turns both the fan (that cools) and the bulb (to prevent the plasma from burning through the glass of the bulb) burn out VERY fast. 1st generation units had 50% of the magnetrons burn out within 6 months. We were told this was due to the power supplies. 2nd gen units seemed much more solid in the power department.
#2 - the fan motor / bulb turner would break/no longer rotate. It didn't appear to us that they had a high enough quality motor on these... a large percentage of them would break within 3-6 months. If the motor stops turning that bulb it goes POOF when the plasma burns through.
#3 - the light is NOT white. it is kinda green.. pretty noticibly green actually. People do not seem to like greenish light. Most of us are used to either a yellowish or blueish tint. We had several people complain of feeling sick.. Dunno why green light would do it, but it didn't make our customer happy.
#4 - the high temps that these units achieve lead to a break down in both the reflectors and in plastics used to feed the light into useful places. We replaced many lights with one of these units (like a 5 to 1 ratio maybe) and then used a plastic tube as a 'light pipe' to deliver the light where it was needed. The material in the reflector would either a) degrade, or b) get deposited on the plastic tube due to the high temps. Also the plastic joins on the tubes would degrade seriously in a short (months) time frame. Maintenance costs were incredibly high.
In short: great idea, bad implementation. I have no doubt that if the engineering of these untis was higher (with the subsequently higher cost) that these would work. But then these already pricey (very) units would not be able to compete with existing technologies (like metal halide).
Crow
I'm not an RF expert, but I'll tell you why I personally don't worry. The 2.4GHz band was set aside as an ISM band precisely because it is very well absorbed by water. Which is how a microwave oven works. The several hundred watts of microwaves emitted inside of the oven will bounce off the metal walls until they get absorbed by something. Usually this is your food. Or more accurately, the water in the food. Which is why it heats it up so well.
You don't want to be around the output of a microwave oven for precisely the same reason you don't want to stick your hand on the stove when it's on. You'll get burnt, plain and simple. With microwaves, you could actually get burnt on the inside. Most internal organs don't like extra heat. Witness how little of a fever you have to have before it becomes life threatening.
Now, back to wireless devices. The power output of your typical 802.11b device is between 30mW and 100mW. A typical microwave oven will produce up to 1000W of power. 10,000 times the power of your wireless card. Can the output of your wireless card or phone heat up your head? Of course. Will it heat it up enough to matter? Not likely.
Ah Yes! Another loving spoonful of alarmist hype! One company has a technology that conflicts with Wi-Fi and I'm to believe that companies with a vested interest in wireless are going to let this happen!
Wolf! Wolf!