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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."
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!
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
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
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.
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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.
If the RF lights get shielding on them then we don't have to worry about them interfering with network devices too much.
Then again, if they DON'T get shielding they'll never sell. Try telling your employees that you are going to replace all the lights in their workspace with lights that spew radiation at the same frequency that their microwave uses, but without the shielding! Sure, the output would be WAY below a microwave, but who wants to sit under a bank of them eight or ten hours a day from now until retirement?
Life is short: void the warranty.
my wife's law school and my workplace are both wired for WiFi access. and while a law school may not have pull... the place i work probably would not roll over and die and let interference destroy their data networks. maybe WiFi for the home starts to get hurt, but WiFi is here to stay, at least in business. it sure beats running hundreds of meters of Cat-5.
-rp
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.
Well, that is true, but the issue at hand isn't really the rule, but rather corporate america's willingness to use loopholes to do business. In effect, an unauthorized RF source is interefering with an unauthorized RF network (or whatever). Since both are unauthorized, they fall in between the cracks of the Section 15 rule, and therefore, could still be subject to legal action. This could also result in a rewrite of the rules by the FCC to account for such issues (which could be good, or very bad, depending).
But most importantly, the courts should (don't read will) be very reticent to kill one company's nifty product in production for anothers. And, I believe that satellite radio is an authorized radio service, so if RF lighting does in fact prove to be a source of interference, then RF lighting is going to have a very tough time. Two established providers v. a new an upcoming technology should be an easy one for any court. If satellite is interferred with, then it is almost a sure bet any WiFi equipment will suffer, and the judge, whose kids may surf the web using the WiFi tech, is most likely going to rule in favor of established products.
Note I'm using the courts in my argument. Due to the FCC's continuing inability to make a decision stand, it is almost inevitible that courts will be involved. Someone will sue someone else in an attempt to force the issue.
Bah
A few years ago I did academic research funded by FusionLighting to improve their product. Without violating any confidentiality agreements, here's a quick explanation of the technology
The source of light is a gas plasma induced by pulsed microwave radiation. Fluorescent and neon bulbs also use a gas plasma, but they have two electrodes running at 60 Hz. Sodium-vapor and Mercury-vapor arc lamps use plasmas, but also with exposed electrodes.
These bulbs have no electrodes (so they last _much_ longer) and run at microwave frequencies (2.4 Ghz). Why did they choose this freqency? Just to ruin your wireless connection? No. They needed high power magnetrons (things that generate microwaves) but didn't want to pay military prices. Well there's already a large competitive market for high power magnetrons, it's called the microwave oven.
The FusionLighting light bulb I worked on was a bit larger than a golf ball and filled with a secret sauce of gases and other stuff. When lit, it was VERY BRIGHT (you absolutely couldn't look right at it) and provided a spectrum of light much closer to sunlight than fluorencent and even incandescent bulbs.
The light bulb is mounted inside a metal screen box which is the microwave cavity. Light can get out of the metal screen but almost all of the RF stays inside. Actually, once the bulb is on, almost all the energy goes into the bulb (that's why it's so efficient). Apparently, enough leaks out to disturb Wi-Fi etc.
The downsides of this technology (other than ruining your internet connection) were: [note: it may have evolved since I worked on it a few years ago]
(1) The bulb plus magnetron was pretty big, very bright, and somewhat noisy. Typical applications were warehouses and gymnasiums, not your home. Example: the Smithsonian Air and Space Museum replaced 88 soldium-vapor arc lamps with a handful of the fusion lighting bulbs. And they were THROWING HALF OF THE LIGHT AWAY by using diffuser tubes that spread it out and kept your kids from going blind when they looked up.
(2) The bulbs took a few moments to warm up when turned on. During that time, the light was a dim blue-violet color.
(3) Like sodium-vapor lamps, you couldn't turn them back on as soon as you turned then off. They had to cool down.
(2) + (3) = No fun if you forget the keys and then run back in to find them in the dark.
I was working on (2) and (3), as well as improving the efficiency, which would lead to a smaller size. We made some progress on all counts.
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Dr. Hodad
Black's Beach Tanning Supply
La Jolla, California