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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."
Is cool.
FP
I guess no one will be bringing these to the lan party =P
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.
...How this will impact the use of fluorescent lighting as a data carrier. Remember This story?
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)
Why not make these play nice and use the lights as repeater stations? Install a recepter on each one, wire'em up to the LAN and have even more ubiquitous access.
Any spoon would be too big.
Steve Stroh
Independent Technology Writer
Specializing in Broadband Wireless Internet Access
P.O. Box 84
Redmond, WA 98073-0084
425-481-0600
www.strohpub.com
steve@strohpub.com
Presented in the Spirit of Sharing that was the most important part of the original Internet. It takes a certain minimum generosity of spirit to play the online communications game. Without it, you fail in the long run. - Jack Rickard
Focus
on Broadband Wireless Internet Access
Steve Stroh, Editor
This article is excerpted from the July/August, 2001 issue of Focus On Broadband Wireless Internet Access - www.strohpub.com/focus.htm and is offered as an example article.
Part 18 RF Lighting
A Potential "Extinction Level Event" For Communications Users Of The 2.4 GHz Band
The phrase "ELE - Extinction Level Event" entered the popular consciousness several years ago as a result of the popular movie "Deep Impact". In the movie, an enormous asteroid is observed to be on a collision course with Earth. The asteroid is sufficiently large that an impact on Earth will cause catastrophic effects, mostly a dust cloud that will block sunlight for many months if not years, triggering the death of plant life, and soon after most animal life.
The term ELE came to mind as I read about a new lighting technology from Fusion Lighting, Inc. (www.fusionlighting.com) that uses microwave energy in a new, very high-efficiency lighting system, dubbed "RF [Radio Frequency] Lighting".
An August 6, 2001 article in the Wall Street Journal titled "Energy-Saving Light-Bulb Maker Battles With Satellite-Radio Firms For Bandwidth describes a battle-in-the-making between Fusion Lighting, Inc. and two companies that plan to offer satellite-based broadcast radio - Sirius Satellite Radio, Inc. and XM Satellite Radio. At issue is the amount of interference that Fusion's new devices would cause to the satellite radio broadcasts at 2.32 - 2.345 GHz, which are considerably removed from the spectrum where Fusion's devices operate - 2.4 - 2.4835 GHz. The satellite radio broadcasters have concluded that Fusion's devices, as proposed, will cause substantial interference to their transmissions.
Left unmentioned in the WSJ article, and only now beginning to be noted by many users of the 2.4 GHz band is that if the Fusion devices are capable of causing such trouble for satellite radio broadcasting... what would the effect be to communications users of the 2.4 GHz band, where the Fusion devices will be operating?
2.4 - 2.485 GHz in the US is used by two very different types of equipment. The older, more well established use of the band is for Industrial, Scientific, and Medical equipment (ISM) such as household and industrial microwave ovens. Operations of such devices are governed under the FCC's Part 18 rules. Basically, Part 18 devices are expected to radiate only - not receive and thus, are not communications devices.
The second major use of the 2.4 GHz band is for license-exempt communications equipment governed under the FCC's Part 15 (15.247) rules.
Because the Part 15 rules specify "robust" modulation techniques such as Frequency Hopping Spread Spectrum (FHSS), Part 15 and Part 18 devices can generally co-exist, for example microwave ovens in a household rarely operate for more than a few minutes at a time, so cordless phones and wireless networks operating in the 2.4 GHz band can continue to operate. Conflicts were anticipated when the Part 15 operation was first envisioned, and the following requirement was levied on Part 15 devices:
(1) [Each Part 15] device may not cause harmful interference, and (2) [Each Part 15] device must accept any interference received, including interference that may cause undesirable operation.
Basically, buyer beware / use at your own risk.
Fusion's RF lighting system is a good example of a Part 18 device. RF technology is useful for any number of purposes other than communications, and the FCC and industry recognized this and set aside various chunks of spectrum for industrial use.
The problem comes that the 2.4 GHz band is now used by an incredible number of number of communications devices - cordless telephones, wireless Internet access networks, wireless Local Area Networks, and soon all manner of simple devices with Bluetooth embedded in them- with an accumulated investment of (at minimum) billions of dollars.
How we got to this situation is that there was steadily increasing demand by various companies for spectrum for wireless networking and related applications, but there were no large swaths of spectrum that were suitable. There were demonstrable needs for wireless LANs in warehouses and hospitals. There were demonstrable needs for temporary wireless links.
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. It was clearly in the FCC's mind that there would relatively few Part 15 devices, and that for the most part they had heard the last from Industry. The Part 15 rules were tough, and it would be extremely challenging to make radios work under such conditions... and, they'd have to develop newfangled spread spectrum technologies that were previously used only by the military and developed at great cost.
But, Industry found the Part 15 "deal" to be perfectly acceptable. Industry understood the Part 15 deal better than the FCC did. Industry's major goal was to be able to offer wireless devices that did not require a license from the FCC, so that such wireless devices could be sold over the counter - to anyone, everywhere. Industry foresaw that there was a market for millions of such devices (I doubt that Industry, at that point, projected that such devices would rapidly number in the billions...)
That there were technical obstacles to overcome... well, that was just a barrier to entry for potential competitors. As we've come to expect, where there is a demonstrated demand, technology can overcome, and that's exactly what happened. The biggest factor that made the difference is the rapid increase in capability of application-specific integrated circuits, and digital signal processors. Taken together, spread spectrum radios could be built, at affordable prices, that met the FCC's Part 15 rules. Gradually, an entire Part 15 industry evolved... far beyond the wildest imaginings of the FCC.
What Will Happen? There are a number of factors at play, and very high stakes, so there are a number of possible scenarios. The first scenario is that, quite apart from its effects within the 2.4 GHz band, the effects of the new Fusion Lighting devices outside of the 2.4 GHz band must adhere to existing regulations. It's difficult to ascertain from what has been published to date (particularly when Fusion Lighting is being very circumspect with potentially damaging details of its proposed product), but it appears that Fusion Lighting claims to meet the "out of band emissions limits" for Part 18 devices.
The counter-argument from the satellite radio broadcasting companies is that even if Fusion Lighting's proposed products are within out-of-band emissions limits, their transmissions are still being impacted.
To which Fusion might be expected to reply (to the effect of) "If a satellite radio broadcasting system is too precarious to deal with other signals that should have been expected, then you didn't do your homework."
The satellite radio broadcast companies' position is that this kind of interference has never been previously been an issue. Etc. You can understand why this is such a hot issue at the FCC.
But, within the 2.4 GHz band... if a Fusion Lighting device is activated, it will severely impact the use of all manner of Part 15 devices in the area around it. For example, 802.11b is becoming very popular in both large and small companies, and becoming even more popular for home use (because to hook the kid's computer up to the cable modem doesn't require any new wires). Cordless phones are also increasingly using 2.4 GHz. What happens when a nearby gas station installs RF lighting... and all 802.11b devices and 2.4 GHz cordless phones for a mile in diameter stop working?
The RF Lighting issue is quite the dilemma for the FCC, which was hoping that Fusion Lighting would be willing and able to modify their device so that it wouldn't cause interference to communications equipment. But that appears unlikely, and Fusion Lighting appears to be within its "rights" to apply for an FCC Part 18 certification to begin manufacturing. But if Part 18 certification is granted and RF Lighting devices become widespread (and it appears very likely that they will, given their inherent energy efficiencies), is the FCC willing to "sacrifice" much of the utility of the 2.4 GHz band in exchange for one company's (at the moment...) product?
The group likely to be most severely impacted by Fusion Lighting devices are Internet Service Providers that are using wireless equipment to connect to their customers. The vast majority of Wireless ISPs (WISPs) use equipment that operates in the 2.4 GHz band. Some equipment is purpose-built for ISP use, and many others use modified Wireless Local Area Network (Wireless LAN) equipment. What all WISPs have in common is that their signals are relatively "fragile". The FCC's Part 15 rules apply equally to equipment used by Wireless ISPs, so the ISPs compensate for low transmitted power with high-gain, directional antennas. This approach allows them to have enough "signal margin" to achieve a reliable link... but if a source of interference appears nearby, the link will likely be disrupted.
It may well be possible to overcome interference in the 2.4 GHz band from RF lighting devices... but doing so won't be inexpensive or easy. For example, link margins can be improved by building multiple hub sites with short paths instead of just a few hub sites with relatively long paths. Another approach is to buy better 2.4 GHz band equipment that is more robust, such as that offered by WIMAN Systems (www.wiman.net).
A long term solution to interference issues in the 2.4 GHz band is to begin using equipment that operates in the 5 GHz band. In the US, there is a total of 300 MHz of spectrum available for license-exempt wireless devices at 5 GHz. 100 MHz of this spectrum is also ISM spectrum, with the potential of industrial devices being operated there also. But the other 200 MHz is "virgin" spectrum and reserved exclusively for communications.
A number of companies now offer equipment for the 5 GHz band, and as the price of RF components for 5 GHz continues to fall, more and more equipment will become available. The emergence of equipment compliant with the 802.11a Wireless LAN standard is expected to play a major role in increasing the popularity of equipment for the 5 GHz band. Where 802.11b offers (theoretical) speeds up to 11 Mbps and operates in the 2.4 GHz band, 802.11a offers (again, theoretical) speeds up to 54 Mbps and operates in the 5 GHz band.
If RF Lighting is an "ELE" to communications users of the 2.4 GHz band, at least there is time to begin "planning for survival" - planning for migration to 5 GHz, study of new equipment, lining up additional financing, etc.
Filename: 0701feat.htm This page is one of a series of pages from www.strohpub.com. This page, and all subsidiary pages associated with it (not including links to other World Wide Web pages) are Copyright © 1997-2001 by Steven K. Stroh. To contact the author, send e-mail to steve@strohpub.com. This page was last updated September 5, 2001.
.
Assuming such lighting causes severe interference tothe 2.4 GHz band, would some government organizationg (FCC or whatever) not regulate this? I would think that I could not produce a product that causes interference to these devices without registration/approval from the right regulation boards.
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
It's the law. If you want to have the unalienable right to 802.11b transmitters and cordless phones, sponsor a constitutional amendment.
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
Whoever has the most powerful transmitter wins. I'm sure Powell Jr. at the FCC loves it that way.
try { do() || do_not(); } catch (JediException err) { yoda(err); }
Yeah, I would imagine that a broad spectrum broadcast at 500 watts would wipe out any nearby... anything. Fortunately, I don't think the lights are going to get very wide acceptance.
--Bennett Prescott
Former Lord Of Packets
That's why 2.4 GHz will rapidy become unreliable for wireless LANs.
Luckily, 5 GHz wireless LAN products (802.11a) are now becoming available (called WiFi-5, I believe). Since they
do not use the 2.4 GHz frequency range, they will not be affected by this issue.
the link to fusionlighting.com works fine. Not a lot of details but it does describe the product, what it's good for and that it is supposed to be commercially available this year.
This sig has been temporarily disconnected or is no longer in service
What the hell do they mean by RF lighting? That makes no sense where RF tech comes into lighting, sounds like spittng out light at 2.4GHz which would be useless... Could someone point out a plausible explanation or is this just a hoax?
XML is like violence. If it doesn't solve the problem, use more.
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
this is all well and good, but the article never describes where these lights are purported to be useful. If these lights are not going to be marketed to the house, Bluetooth and others will be unaffected in the home. I seriously doubt that any business with any substantial investment in wireless for their offices would use these lights if it involved a replacement of their wireless infrastructure. Yes, there is a danger to wireless communication posed by the use of these lights. But then again, whenever I have my computer with its case off too close to my TV I cant get half of the broadcast channels.
--Kevin
DECT is not a user of the 2.4Ghz Band. It uses 1.9Ghz.
I should use this sig to advertise my book ISBN-13 : 978-1501515132.
Does this mean that I have to have a wi-fi and a hi-fi? You know some of us need to get with the technology bandwagon :-)
What OS do you want to abuse today?
As far as I know this spectrum was always reserved for Industrial devices. Whoever built a communication device for this band did it knowing the fact very clearly it was not their territory and took a risk that Microwave ovens would not become very popular.
Now the ghosts of that mistake are catching up with them.
And its not only industrial even medical applications use this band.
Does anybody have any idea if 802.11b will work in a hospital?
**Life is too short to be serious**
Yes. The first of these light fixtures marketed will come in a huge steel box with a fake wood veneer.
There are no penguins in Alaska. Funny joke anyway.
Or, just weigh the $$$ involved. Which is a bigger industry, IT/Communications, or lighting manufacturers? Seems a no-brainer for the FCC. I fully expect them to re-regulate RF lighting.
Also, more info on RF Lighting can be found here.
--
Repeal me, NOW!!!
Thank you.
that was great
+1 troll
So what's the point of this article? This article makes me ask more questions than it answers. It's essentially two pages worth of "switch to WIMAN or 802.11a" and is out dated...
:wq
From the article...
(1) [Each Part 15] device may not cause harmful interference, and (2) [Each Part 15] device must accept any interference received, including interference that may cause undesirable operation.
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.
Let's see an electric use cost comparison between this RF lighting and fluorescents. It's pretty slipshod that the article didn't bother to address the question of whether this lighting offers significant savings.
Until it's clear that there are compelling cost advantages associated with microwave lighting, the issue of whether this technology could endanger communications doesn't merit discussion.
I'm generally "Interesting," "Insightful," and even "Funny" here. What the hell happens to me at parties?
http://www.fusionlighting.com/sulfur.htm
These lights are really cool. They are even more efficient than high pressure sodium lamps but give a spectrum very similiar to sunlight.
-Zach
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."
Earlier today it was the dual-screen laptop. They seem to publish these stories totally uncritically.
Dudes, if you're that desperate, just regurgitate something from Space.com, Wired News, or the Register.
This is not a troll.
But they are perfect for large warehouses. US Department of Energy headquarters in Washington has had one of these since 1994.
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.
Seeing as this technology uses tiny microwave emitters to excite sulfur ions what effect would it have on pacemakers? If they have to sheild it for pacemakers and stuff then shouldn't the effect be minimal or seeing as the 2.4 ghz area is open can they just dump as much radiation as they want into that spectrum? I mean I don't see problems when I use my 2.4ghz cordless of WiFi laptop when my microwave oven is running, so shouldn't the lights be sheilded to the same standard?
Also, I believe Bluetooth, at least, uses an unlicesnsed segment of the spectrum. So, unlike me setting up something that jams, e.g., 99.5 FM or channel 5 or something, this would be (currently) unregulated.
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.
did you even read the article? no, of course not, that would require some sort of wasting time before you whore popularity.
thank you. It's always nice to have someone acknowledge the hard work that goes into trolling. Specifically the finger cramps from constantly refreshing slashdot. My finger hurts so much right now, that my girlfriend isn't going to get any action tonight I can tell you that
Yes, I would assume you're right.. "legally" we don't have a right for RF technologies to always work. FCC regulated or not, it comes down to your local area when you're using or considering using wireless phones, WiFi, or other wireless devices. When I was in grad school I was in a building where 2.4GHz was kind of noisy, I expect it was due to science research experiments and a steel-frame building. We just bought antennas and didn't worry about "legal" reasons. Seems everybody is too quick to complain about legality these days.
I think the real issue is more practical, who buys the technology not knowing that it will heavily interfere with certain wireless equipment. (I'm thinking office environments are the biggest issue) Doesn't the consumer have a right to know things like interference before purchasing a product? After reading the article I personally got the idea that I need to check out the lighting technology and be cautious of where it is installed. That's all, it's an old technique where you just don't buy something if you don't like the side effects.
__ No registration required to read this message. They did it in the Matrix.
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.
My internet access is more important than my co-workers ability to see, so none of these lights for us.
If you lease an apartment and you find squatters living there, do you (a) ask them nicely to leave since that's your space now, or (b) call your landlord to have the police throw the freeloaders out?
This is no different. Fusion Lighting is playing by the FCC rules, while all the Bluetooth, Wi-fi, and cordless phone manufacturers were getting away with squatting on a frequency that they knew could be a problem down the line, but that no one was using yet. Now that someone has a legitimate claim to the frequency, they're crying foul? BS...you have no basis for that frequency in the first place. Move to the 5GHz band, establish a right to that band, and fsck off on the 2.4GHz band. I do feel sorry for the people who have already invested in devices running on that band, but you need to do your homework folks.
Ignorance is no excuse.
Rule #1 -- Politics always trumps technology.
It sounds like that rule doesn't apply to the 2.4 GHz band. That band was reserved specifically for use by Microwave ovens, etc., which transmit but don't receive.
Manufacturers started using it for communications equipment because you don't need an FCC license to use this band - you just have to prove that it doesn't create too much interference in other bands. As long as you stay in the 2.4 GHz band, then the FCC, more or less, doesn't care. All you have to do is make your device work well enough for people to buy it.
This also means that if some manufacturer wanted to deliberately create a device to block all 2.4 GHz communications in a local area, they could apply under Section 18 (or whatever it was) to have such a device approved. There's nothing that the cordless phone manufacturers could do about it.
Frankly, they should have known better. However, we tend to support a throw-away society, so you'll just have to go and buy something that works in the 5 GHz band now. At least now there's bandwidth specifically allocated to communications in that frequency range.
"I have never let my schooling interfere with my education." - Mark Twain
wireless is gay
OMG BIG PENIS ATE MY SOUP
Good luck to you. But please, for the love of god, do not fly Airbus! -- Airbus, the European jet manufacturer, is planning to build concealed cameras into the light fittings above the seats in its aircraft. The idea is to let the crew monitor passengers and spot hijackers before they strike. The cameras also work in the dark. The move is part of an attempt to reassure people who have been frightened off flying since the 11 September attacks. At an airline technology conference in Prague last week, a delegate from the VALK Foundation said that before 11 September, none of the 4000 people it has helped to overcome their fear of flying had ever cited hijacking as the root of their fear. But since then it has become the main fear for a third of its clients. The industry hopes that well-publicised improvements in airline security will quell passengers' fears. Airbus, working with American aerospace technology company Goodrich, thinks the best strategy is to let passengers know that everyone is being watched by hidden cameras. Infrared image One plan Airbus is considering, says the firm's cabin security expert Rolf Gödecke, involves hiding a tiny camera inside the light fittings above each passenger seat, surrounded by a ring of infrared LEDs. The cameras will normally work with ambient light, but switch to infrared when the cabin is dark. Black-and-white images captured by the cameras will be fed to screens in the cockpit via the cables used to distribute pictures to seat-back video screens. Although only some lights will have cameras, potential terrorists will not know which ones. A less ambitious system, which Airbus is now fitting to all its new planes, will monitor the area behind the cockpit door. Under new rules, cockpit doors are being reinforced to protect the flight-deck crew from attackers. But they still need to open the door to get to the toilets and to let cabin crew members bring them meals and drinks. So Airbus is putting three overhead cameras with wide-angle lenses around the cockpit door to send pictures to an LCD screen in the cockpit. "Two cameras leave a blind spot," says Stein. "If carefully sited, three give a hijacker no hiding place."
http://www.fusionlighting.com/technology.htm
That's an inside like the the RF lighting technology.... The company's main page doesn't have any link (under construction). Pulled that from google.
"Focus on Broadband Wireless Internet Access has an article [cached by google ]
Note to article posters: Do more of that cached by Google stuff, I like that.
Adidas To Bring Back Sneakernet
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
All this talk about interference between WLAN and Bluetooth is more or less rubbish in my experience. Both at work and at home, I work every day with both Bluetooth and WLAN at the same time and I've never had any problems or slowdowns of either one. On my laptop, I have both and both are enabled at all times - no problems, ever. At work, just two rooms over from mine, people code Bluetooth code every day with several Bluetooth devices, some of which are experimental. The same office space has a WLAN network and nobody ever complains about interference.. *shrug*
I hope problems like this, prompt the public to pressure the FCC. Between them and the Patent office, we should be screaming to our politicians that lack of forsight in these departments is going to slow progress. The government needs to hire some intelligent people for these departments, and stuff like this won't happen quite so frequently.
Um, this is my sig.
"and save the environment".... I like environment models that understand that there is an environmental impact represented in every dollar spent/received. Can these lights truly save the environmental impact caused by the forced restructuring of billions of dollars worth of equipment and development time? Don't forget that developers consume light and energy. Production of new telephones and other devices to replace those obsoleted also consumes light and energy. The environmental impact of a environment saving technology deployed wrongly can be devastating.
If this could be used correctly with a narrow enought beam this could be the Ultimate Wifi fire wall put these lights all around your building pointing outwrard and no one can send signal into your building to snoop on your network. but they would have to figure out how to limit their effectivness so that you don't block the next buildings network.
madness takes its toll please have exact change
The amount of interference caused is less than the article is making it out to be. Although it would require that procautions be taken (an EXTREMELY high amount could disrupt a transmission). Under normal conditions, RF Lighting hurts the signal a little bit, but nothing as significant as to signal the end of wireless as we know it. Just saying.
Well, the only other possibility is that he screwed a midget black nun (in a tuxedo). Guess it depends on what's more probable.
Flourescent lights and CRTs have been causing interference in electric guitars for many years. Not to mention the 60hz harmonic from the wall that causes 'pickup hum'.
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.
There are no penguins in Alaska. Funny joke anyway.
Maybe at a zoo?
Speaking of images (don't want to get modded Offtopic, after all), I still haven't found a good Gandalf wallpaper image. Thanks to all those who have helped, now let's give it one more go. Remember, stoned is the look I'm going for.
Karma: Good (despite my invention of the Karma: sig)
okay, if their lighting disrupts our communication, is there a (legal) way to make our communication disrupt their lighting? this is our bandwidth, we were here first. if they want to destroy it (i.e., not play nice) then they better be prepared.
-rp
Ugh. Now I'm going to be forced to add rows of copper pennies to my burgeoning tin foil hat.
The page includes the statement that a golf-ball-sized device could have the light output equivalent to 10,000 watts of incandescent bulbs (100 100-watt bulbs). Granted that they are more efficient than incandescent, how hot is such a device likely to get during operation? Even at 90% efficiency, a device that size converting 1,000 watts to heat is going to be damned hot.
His post only got a score of "2", and now the slashdot community is going nuts about a post saying just about the same thing... Give that guy some credit..
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.
One thing that strikes me about all of this is that places that install high efficiency lighting are probably companies of various kinds. These same places will generally also purchase things like wireless networks (802.11b is all over the place now from gas stations to big companies). If a company finds that their new lighting system will disrupt day to day business, I doubt they'll invest and this will be bad news for Fusion Lighting since 802.11b was there first.
I was thinking more like the see through door of the microwave...
'He was a dreamer, a thinker, a speculative philosopher... or, as his wife would have it, an idiot.' - Douglas Adams
Perhaps someone could answer a question for me that I've always wondered about.
Exactly WHY are devices, such as the 2.4 GHz Part 15 devices mentioned in the article, required to accept all interference? What is gained by not allowing products to be [shielded] from unwanted interference/RF signals?
"You know your god is man-made when he hates all the same people you do."
Is that you?
Best Slashdot Co
I've been wondering about this for a while. Why is that people seem to be so unconcerned about frequencies that operate in their microwave to cook food, but are perfectly willing to put handsets that operate at similar frequencies right next to their head, or laptops that use Wi-Fi in their laps? I know it is based off of different power outputs, but still some of these we use for hours at a time. It hardly seems safe.
Now lights with a potential solution being offered of going up to the 5 GHz spectrum for communication devices.
Amateur radio operators I plead with you (since I am one, but am not active enough to remember some of this stuff) to provide info on use of various handsets at high frequencies next to your head.
No it has a "we have been slashdotted... Underconstruction page..."
Try The real start page
Did you bother to read the artical? No, well then just shut up.
The point being made is the desirability of making use of the 5 GHz band, and doing so befor RF Lighting becomes common place.
Pay attention to what Part 15 and Part 18 of the FCC regulations are.
Unlimited growth == Cancer.
That works fine for most buildings. There are only perhaps a dozen ovens at most, and they only run for a few minutes at a time. But there could be hundreds of RF lamps, and they could operate 24X7 in a warehouse environment. The lamps could potentially make the RF environment orders of magnitude more hostile to data service, so that's why people are in a lather over it.
-- ;-)
Kuro5hin.org: where the good times never end.
The really stupid part about that is eventually 5 GHz will have the exact same problem. Going to 5 GHz is not a real solution, it's just delaying the impact of the problem.
Anything is possible given time and money.
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...
Did you remove all the shielding from your gear, or does your boss walk around with a 5 watt analog brickphone strapped to his ass?
:wq
One ring to rule them all. The (_O_) in Goatse.cx
There's a growing concern over WiFi and its health effects since it operates so close to the microwave oven frequencies.
All we need to do is let the soccer moms and paranoids of the world know there'll be microwave light bulbs cooking the brains of our children in our local schools. That'll pretty much take care of the problem. And fsck up Fusion Lighting's chance for a killer IPO.
I tried every decent and legal way I could think of to resolve the issue w/the business before I rented the chicken suit
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.
-
- - You can't take something off the Internet! That's like trying to take pee out of a swimming pool.
I had a feeling this would happen.
There are far too many devices operating @ 2.4Ghz...
as gee-whiz-cool as Wi-Fi is, you guys should have known better!
What's a little CAT5 gonna hurt anyway...
(faster, cheaper, more secure, less fragile)
FOR SALE : WAP + WIC's...must sell, getting new 5Ghz gear.
(not intended as troll, but mod away)
Innovation will occur where it's allowed to occur.
Or, as has been said, Innovation is a wildflower; you cannot choose where it will blossom, but you can choose where it won't.
The thing about things we don't know is we often don't know we don't know them.
Oh...like the door on our microwave that causes the 2.4Ghz baby monitor to freak whenever it's run?
:)
Hmmm...is the baby awake? No..the neighboor just turned on their new lights
n/t
--- What?
Keep passing the open windows...
So maybe there should be some lobbying of delegates to the next international frequency allocation conference, which I think is next year, to get a recognised allocation for "portable data communications equipment".
While 100% correct, that is not nessecarily the end of the story. The FCC regulates spectrum for the common good. The use of section 15.5 expanded far beyond the FFC's expectations. The FFC has the *option* to alter its rules to take the current reality into consideration.
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- - You can't take something off the Internet! That's like trying to take pee out of a swimming pool.
has anyone studied the health effects of transmissions in the 5ghz department? Thats double the frequency from 2.4 ghz. I frankly dont like all these tiny microwave transmitters; cellphones, lan, bluetooth, phones, and now lightbulbs... studies in the area are always controversial but some of them are kind of alarming. Maybe my brain is fried already...
Of those to whom much is given, much is required.
that was the most incoherent sensless troll ever.
+5 to j00
What I don't understand is why RF lighting poses a threat when WiFi devices ARE currently able to handle the interferance from other Class 15 devices? Do they bombard the entire spectrum to generate enough energy for the bulbs to convert to visible light? I doubt it, but don't have time to dig for more info as others have tried and failed to find much.
If the spread spectrum nature of 2.4 Gig communications devices has protected them to this point, why worry now, especially since it looks like this company/product is now just an afterthought.
I think it's time to chill out on this one.
Keep passing the open windows...
The sheild on the microwave stops the band that would make your eyeballs go pop. Not 2.4 GHz.
Want to see every step I took to start my company? http://www.rowdylabs.com/blogs/pitchtothegods
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.
Never mind paintball -- a new technology known as RF lighting has just added a whole new dimension to war driving.
Previously the province of snoops, voyeurs and bandwidth cheapskates, the latest sport for all those unemployed twenty-somethings who still haven't maxed out their Amoco card has just entered the mainstream!
Take out your neighbor's Internet access -- hell, make everyone on the block wish they were wired up again with the new portable, battery operated tight beam "RF Strafer". It even plugs right into your Mini's cigarette lighter!
...just stupid people. So here's a stupid question:
if RF lighting exists at "[a] frequency that humans can't even see" then how the fuck can it illuminate anything?!?
The author's from Redmond, the home of FUD. He probably got infected passing Microsoft oneway.
A quick glance: "yadda yadda to wipe WIPO asses" Needless to say I proceeded to grab a beer.
If you shoot out the globe with a BB gun, does the magnetron continue to emit microwaves?? Just until it burns up from not having a load? Let's find out.
The radiated power that makes it outside the bulb is likely very low. Remember, these devices are designed to save power versus a conventional incandescent lamp, not hose the spectrum with wasted emissions. Has anyone seen any real numbers that could form a basis for estimating the interference potential? Measurements have been made on similar lighting devices, see: http://www.its.bldrdoc.gov/pub/ntia-rpt/99-366/ These measurements were made with the receive antenna ~ 0.5 meters from the device. These bulbs are extremely bright, and are designed to light factory floors, stadiums, and other large areas where the devices likely will be a factor of 20 or more (36 dB) farther away.
DECT uses 1.8GHz in Europe and various parts of the world... not the usual 2.4GHz as used by digital cordless phones in the US, my 802.11b and DECT phones coexist peacefully.
The light from an incandescent bulb varies at 120Hz. It doesn't turn off, but it does vary.
"I'm not impatient. I just hate waiting." - My Dad
Not quite. Heat is the ambient kinetic energy of the particles (atoms/molecules) that make up the thing that it hot. They're effectively shaking back and forth more or less rapidly. Hot objects may radiate energy in the form of photons, but heat, itself, is just kinetic energy.
But the Michelson-Morley experiment showed that there is no ether.
"I'm not impatient. I just hate waiting." - My Dad
"We demand rigidly defined areas of doubt and uncertainty".
"I'm not impatient. I just hate waiting." - My Dad
operations shall accept any interference that may be received, including interference that may adversely affect the operation of the units authorized under the waiver.
This rule has always baffled me. can somebody plese explain the reason for this? What is the advantage of having a cell phone that craps out when you go under power lines, and of having a law that says there is nothing you can do about it?
Sounds to me like just another example of the Man trying to keep us down...
SpyDock: Scientific Python in a Docker container
This company has been working with 3M and a few others since at least the mid-nineties to make a microwave powered commercial lighting solution.
They're finally about ready to deploy a finished product and in the meantime the spectrum they've got every legal right to use has been crowded with the Wireless craze. Fortunately though the 5 GHz spectrum still has some free spectrum for wireless devices.
Also, the article takes a sort of doomsday approach. Basically all the lights will do is generate a lot of static on the 2.4 GHz range, so your 2.4GHz phone will drop calls a lot, and have terrible fits of static, not stop working completely. Wi-fi will run into the same problem, you'll get fewer packets through, and less bandwith (and range) as a result.
Also, the 1 mile radius was exagerated. the only places that the static will be strong enough to cause a blackout is probally 100 meters. However, a busy street with lots of gas stations could cause 2.4Ghz free zones within a city, where not even a blutooth device would work without lead shielding.
I'm sure this will lead to zoning laws about where this light can be placed, at least in tech friendly cities.
https://www.gnu.org/philosophy/free-sw.html
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
Doing this would imply that the lights are receiving within the allotted spectrum, which capability would necessarily disqualify them for Part 18 status.
But the Michelson-Morley experiment showed that there is no ether.
The Michelson-Morley experiment showed that the ether was not detectable by the Michelson-Morley experiment. Einstein hypothesized that the ether is not detectable at all, and that hypothesis is likely true. Whether or not the ether exists is purely a matter of definition. You can define ether as "the medium through which light propagates", or you can define the speed of light in a vacuum to be c. If you want to keep away from ether, then I'll modify my definition of wave to:
"A force through which energy is transferred from one particle to another."
Which is admittedly an out of my ass working definition, and is subject to change should you present a counter-example.
Cool! Fire some of these near a wireless ISP and you've got an instant (though probably very obvious) denial of service attack! Any bets on when the first one will happen?
;-)
"Remove this spammer from this network or we will TURN ON THE LIGHT!"
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!
Couldn't the RF Light manufacturer just shield the light fixtures e.g. a Microwave Oven?
No. I saw this thing on Hometime a few years ago.
Imagine a regular light bulb where the glass part is removable from the base and filament inside. Where the filament normally is there's a wire wrap (maybe more to it than that). The glass part is coated on the inside, with a coating that glows when hit by RF. Put the glass part on the base, it glows. Take it off, it doesn't.
To shield this, you'd have to put the shielding outside of the light bulb, which would block the light.
My God, it's Full of Source!
OUTSIDE_IP=$(dig +short my.ip @outsideip.net)
Things that transmit in the 2.4Ghz ISM band have to follow the rules. It may be unlicensed, but it's not without rules.
Power levels would have to be within tolerance, as would stray EMI from the units, as would a lot of other things.
I have every room including the attic, closets and garage in my house equiped with energy efficient RF lighting, and my 802.11b is working fine
Errr you mean 60Hz. I can't think of anywhere that uses 120Hz for power (might exist, but I can't think of it :)
120Hz.
There is a positive and negative alernation of the 60hz cycle. A complete cycle goes from 0 to +max to 0 to -max to 0.
2x 60Hz = 120Hz
when we go the the local gas station lit by these lamps?
Last I knew, folks with pacemakers were to be cautioned about microwave oven usage (remember that sign on the 7-11 door?). Should we expect traffic signs that indicate you should take the next exit or risk "the big one"?
http://www.osti.gov/html/secretry/tp950429.html
I'd buy the lights.. Look at the cost savings, nearly unlimited lifespan, and as much as 4x as bright
Seemed to me like an advocation of 802.11a more than an argument against this RF lighting thing.
:)
Conspiracies? Sure I have a few.
God is real unless declared integer.
With a florecent light you go from zero back to the full brightness and back down 60 times a second, whereas a incadecent light will from like 100% to 99%... There is a change, but i wouldn't really call it a 'flicker'.
autopr0n is like, down and stuff.
First, the article mentions the Section 15.5 rules and considers the issues carefully.
Second, you are a moron. If you would go visit the company's site you would see them bragging of 80% efficency of transmision. While that's all well and good, 20% of your juice is a lot to throw away and I would not put these bright little bulbs in the environmentaly friendly catagory. Want clean domestic electricty? Start building nuclear power plants.
The crux of the problem is the limited and wasteful alocation of specturm by the federal government. Fusion lighting's boast of 80% efficiency came from a 430 MHz transmitter, not a magnetatron operating at the only frequency left open for people to use as they please. There are 69 channels on my TV reciever but only five broadcasters in my town, how about yours? If the FCC alows the abuse of 2.4 GHz it will be to protect conventional telcos, ISPs and large publishers from the freedom of expresion technology can give us. It will be a vastly stupid thing to do, but that's why comercial radio and TV is devoid of anything entertianing or educational.
There it is, plane as geometry. If you are in favor of wiping out all 2.4GHz comunication instead of allocating more spectrum to the people to use as they please, you have a pin head.
DMCA, Hollings, Palladium. What might have sounded like paranoia is now common sense.
URL for fusion lighting which gets behind their 'under construction link'. Url has links leading to the rest of the site:
http://www.fusionlighting.com/special.htm
I don't really think this is going to take off. We already have tons of diffrent ways to emit light. I doubt the cost diffrential of these lights would really be less then the loss from not being able to use 2.4ghz devices.
I mean it's not like everyone is going to go out and get rid of their old lights.
autopr0n is like, down and stuff.
This reminds me of a Friends episode where Ross goes: "what?!? condoms are effective only 97% of the time?!?" And Raechel points out that it's on the box.
I don't see any evidence of why this would be so catastrophic. I can't imagine why a lighting system would be using anything but a narrowband transmission, whereas all the communication technologies use spread-spectrum techniques to avoid exactly this type of narrowband interference.
:)
Secondly, the RF lighting seems to be targetted at industrial applications (e.g. lighting warehouses and factory floors) without the need to run cables - *exactly* the same market for RF comms technologies and for exactly the same reasons. The RF lighting people are the new entrant, so if *they* don't interoperate then they'll be the one seeking chapter 11
If these lights truly become widespread over the next few years, how will that affect ground based radio astronomy with all the extra interference?
And could the intereference add up enough to affect newer space observatories like CHANDRA?
"I'm about to drop the hammer and dispense some indiscriminate justice!"
I have no vested interest in Wi-Fi. I personally am waiting for Ultra Wide Band devices to become prevalent. These devices supposedly cannot be jammed by something like RF lighting or other current methods.
I say do your homework *before* investing in the latest technology, or face being screwed in the arse later. If you can't afford to switch to technology that actually works, then don't buy into the one that does not. Simple? I think so. Reasonable? Definitely.
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.
-------
Dr. Hodad
Black's Beach Tanning Supply
La Jolla, California
yes, Nikola Tesla proposed this at the mechanically-interrupted RF rates that top out at 2 MHz in a lecture way the heck back in February, 1892 (yes, that is before the automobile) to the Institute of Electrical Engineers in London. read along and pay particular attention to the "single-terminal electric" effects into our old friend the Ether if you have a copy of the periodically-availiable Barnes and Noble reprint "The Inventions, Researches, and Writings of Nikola Tesla", 2e, Thomas Commerford Martin, dedicated December 1893 and reprinted (c) 1995.
unknown to Tesla at the time, since he was some 4 or 5 years after the Edison Effect and writeups that looked like vacuum-tube powered Marconi aerials in patent papers, and some 8 years before Marconi sent ethereal waves across the Channel, this became known as electrostatic waves that had strong edges and generated an equally strong RF field.
no "one-button electrical" patents allowed, there was one over 100 years ago.
if this is supposed to be a new economy, how come they still want my old fashioned money?
...but what about the effects of the RF lights?
What happens when a nearby gas station installs RF lighting... and all 802.11b devices and 2.4 GHz cordless phones for a mile in diameter stop working?
Is this total FUD or is it grounded in facts about these lights? Personally I don't like the idea of RF lights that would interfere for miles. I woudl think they'd need suficiently more power to make light than a cel phone or 802.11 card ( > 4W?). A previous post mentioned that 2.4GHz is the resonant frequency of water. There is some water in gasoline. Sooooo.....gas stations are going to begin randomly exploding?
If my microwave doesn't kill my cel phone connection, it must be shielded prety damn good (it's a big ass 1500W). How come they can't just shield the lights and eliminate the problem?
CAn'T CompreHend SARcaSm?
Security is now possible as long as your physical infrustructure has a perimiter of these RF lights.
you should study before you make such rude and arrogant posts.
e n.htm
If you would go visit the company's site [fusionlighting.com] you would see them bragging of 80% efficency of transmision.
According to the U.S. gov't, the efficiency of an incandescent electric bulb is 5%. Kinda makes 80% worth bragging over, huh?
http://www.sandia.gov/media/NewsRel/NR2002/tungst
As for the fact that you were modded up for your ignorance and lack of respect for your fellow slashdotter, I'll let your own words speak...
you must have been modded up as a denial of inteligent conversation
They've done it again: "New Lightning Technology to Wipe Out Wi-Fi Access". Well, no shit. Lightning will wipe out pretty much every computer component it touches.
Focus, focus.....oooohhhhh, lighting.
--
"Outlook not so good." That magic 8-ball knows everything! I'll ask about Exchange Server next.
I have been a bit concerned with the issue of rf 'polution' in this area
of spectrum for a while now. I am no expert on the subject, merely an
undergraduate BoC student, but the only solution that I can think of is legislation
that requires homes to be built (including extensions on existing structures) with
some level of faraday shielding. The problems with this are that there are relatively
few people who are actually affected by this and forcing the many to incur costs to
'support' a minority doesn't go down well with most people. And then you have
the law-enforcement issue, such shielding will prevent or diminsh the reception of
TEMPEST radiation and become an obstruction to the course of justice.
As the effect on humans by EMR in regards to carcinogenic factors has not
resolved a conclusive answer, the argument cannot be put forth that such shielding
will reduce the likelyhood of cancer, this in itself would be enough for most people
to willingly install such shielding.
From an environmental issue though, the increased efficiency of RF lighting is
great, but the reduction in the generation of greenhouse gasses is offset by the
generation of RF pollution, as my grandfather would have said, "...wish in one
hand, and shit in the other." The carcinogenic properties of EMR need to be
investigated further in order to make people listen and think about these issues a
bit.
I've heard this before. This was going to put us all out of business when I was at Metricom in '96.
You have violated Robot's Rules of Order and will be asked to leave the future immediately.
I think the coolest thing about this post is that someone actually checked to see if the site was cached on google. Many a time I have clicked on a /. link to see the site unreachable or dropped.
The Subject covers it all.
But the Michelson-Morley experiment showed that there is no ether.
That's good. Ether puts me to sleep.
(Waits for comedic drumroll...)
"Face it, a nation that maintains a 72% approval rating on George W. Bush is a nation with a very loose grip on reality.
Modern electronic ballasts run the fluorescent tubes at around 20kHz. I doubt you can see flicker at that frequency.
Hey kids, there's only 5 days left 'til Yak Shaving Day!
Hz, which is a measure of frequency is the number of times a cycle is completed in a second. A complete cycle consists of one max and one minimum. Therefore, if the are 60 maxes and 60 mins, the frequency is 60 Hz
T Money
World Domination with a plastic spoon since 1984
This technology will never get off the ground, heard about last year, article is typical sensationalism, what I'd expect out of a newspaper or tabloid
Yes, but a resistive load (such as an incandescent filament) does not care about the direction of current flow. In a single cycle, there is a current flow in the positive half cycle, and a current flow in the negative half cycle. In other words, there are two current flows per cycle, or 120 current flows per second. (or more important to our discussion, there are two points of no current flow per second, or 120 hz rate of no current flow.)
"I'm not impatient. I just hate waiting." - My Dad
That's a great line! I'll have to use it somewhere. "The failure of the X-detector to detect X shows that X is not detectable by the X-detector." I love it!
"I'm not impatient. I just hate waiting." - My Dad
This is supposed to be a thread on light bulbs that blot out the growing free wireless internet. Oh well, there's always a legal solution to technology that treatens established interests.
DMCA, Hollings, Palladium. What might have sounded like paranoia is now common sense.