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Magnets To Replace Bluetooth?
aceat64 writes "News.com is carrying a story that suggests magnets could eventually replace Bluetooth as a cheaper and more energy effiect wireless solution. The concept of magnetic induction isn't new, but Aura has managed to shrink the technology onto a single chip. The first device to be made using the technology is a wireless headset that will cost between $60 and $80."
Talk about lack of ambition.
This is JUST what we need! A bunch of wild magnetic fields around our electrical equipment! I can't wait to get an adapter for my computer, there's space in the case right next to my hard drive...
-- Dr. Eldarion --
Correct me if i'm wrong but dont most Radio transmission technologies use some form of magnetic induction in order to achieve their goal. Last i heard passing electricity through a coil produces a magnetic field. Whats new here?
Electronic Music Made Using Linux http://soundcloud.com/polyp
All my credit cards seem to be erased.
Expect carrier pigeons crashing into your cell phone.
Magnets... the geek's natural enemy, even more so than fresh air and natural light.
Be you Admins? nay, we are but lusers!
Bad news for Iron Man.
"If you want to improve, be content to be thought foolish and stupid." - Epictetus
I'm positively repelled by this, flux you very much.
Just another day in Paradise
So the hapless doofi who've spent years thinking a) magnets can heal them and b) phones can give them cancer must be delighted with this new headset; it'll fix those brain tumours right up.
D'you think it's coincidence that the company who came up with this is called Aura?
How can you replace a technology that nobody actually *uses*?
I can just now see the new line of infomercials talking about combining the freedom of a wireless headset and the 'healing power' of magnets! Sweet Jesus...
OK I RTFAd and unless there has been a change in the fundamental laws of physics and the properties of electrical and magnetic fields then this whole thing is just BS.
You can NOT get a varying magnetic field without also getting a varying electrical field. That is the way the physical universe works. If you can not vary the magnetic field... how are you going to send a signal from the transmitter to the receiver?
-DU-...etc...
"Don't sweat the technique."
'At the heart of the new interest in what's known as "magnetic induction" is Aura, or so claims the nine-year-old chipmaker'
quick, somebody stop these fiends!
I'm a rabbit startled by the headlights of life
Developed in the late 1950s, magnetic induction never really caught on
Gee, silly me, and I always thought Faraday developed "magnetic induction" and that it was in wide use. But, hey, it has turned out that, contrary to my own silly ideas, Gates actually invented the Internet and that BT invented the hyperlink, so I must be wrong on Faraday as well.
I'm wearing metal braces, you insensitive clod!
Marketing bullshit
My bluetooth headseat lasts far more than 2 weeks on 2 AA batteries, and I use it for several hours every working day.
They obviously have a useful product if it can last three months on one battery, but saying "only a number of hours" for bluetooth equivalents would be like saying a DVD can store a whole movie but a CD can store "only a few seconds of video". Big marketing exaggeration, which makes me distrust them from the start.
also in news, segways could eventually replace cars on commuting, rocket packs could eventually replace aeroplanes, slashdotter could eventually get laid..
you get it, anything could eventually do anything.
(and bluetooth is not useless, obsolote tech. it's pretty useful, and if you're bitchin that you don't need a cellular then it really doesn't make much sense to bitch about not needing bluetooth fo r it)
world was created 5 seconds before this post as it is.
I installed one at my home yesterday, and today my hard drive isn't working and my monitor's got all sorts of funny colors on it. I'm posting this from work... I think I'll install one here to trouble shoot.
Just a se
--
RumorsDaily
A broadcast antenna is a magnet, an electromagnet, one that changes polarity many times per second, and that varying electromagnetic field is what induces a response in the receiving antenna. This is called radio transmission (see Marconi, or better yet look up Heinrich Hertz or James Clerk Maxwell.) If this so-called technology is claiming to transmit information using a static magnetic field they are full of little red ants. Phooey.
The higher the technology, the sharper that two-edged sword.
"Hey, look over there it's bluetooth!"
"What, where?"
"Oh, sorry, you missed it."
Dacels Jewelers can't be trusted.
Like many here, I was very skeptical when I read this article -- the reporter is clearly a total sci/tech ignoramus (you gotta love the totally redundant "cordless cell phone").
So I went to Aura's website for more info. Here's their blurb:
While the concepts behind magnetic induction communication have been around for decades, Aura's engineers are the first to develop and implement practical solutions capturing the benefits of this technology.
Conventional radio frequency (RF) wireless communication systems are optimal for sending large amounts of information and communicating over long distances. However, this consumes power, creates information security issues, and results in interference and "crowding" among devices. A good example is in the 2.4 GHz band where simultaneous operation of a cordless phone, WiFi network and Bluetooth headset is frequently not possible without severe degradation of Quality of Service. In sharp contrast, LibertyLink's magnetic communication operates in a "bubble" that envelops the personal space of each user and is - by the laws of physics - inherently private and secure. The result is an easier to use, lower-cost system that makes far more efficient use of power and bandwidth than conventional RF solutions. By selecting a technology that limits the range and bandwidth to only what the application requires, Aura achieves a very substantial savings in power with all of the simplicity advantages of LibertyLink: dedicated communication channels, no bandwidth sharing, complete frequency re-use between bubbles, worldwide regulatory flexibility, and reliable coexistence with WiFi, CDMA, TDMA. and GSM transmissions.
Still pretty vague -- how the hell do they handle interference issues in this "magnetic bubble"? Do they supply Faraday cages for your PC/monitor?
Assuming this isn't all complete bollocks, about which I'm going to hold an open mind, as I'm not entirely sure how this thing would work near computers or pylons, or electrified rail tracks, or power mains, unless it has some AMAZINGLY good filtering in it.
Anyway, assuming that, does that mean we get a chip on a usb stick (say), that would allow Van Eck Phreaking to be done at home? I mean, if you can send useful amounts of data through this technology, it must be good enough to pick up clock signals and keyboard presses?
I know this post is amazingly vague, but so is the technology.
I know how magnets heal people! you take a large magnet and beat a pseudo-spiritual idiot over the head with it, thus you healed the world of one less germ! I read this headline and saw "magnets" and first thing that came to mind was "erased hard drive" so, replacing a technology that no one uses with a technology no one will use.. smart idea! I think I'll start selling AOL cd's instead of music cd's to get my business flourishing!
Actually, I have to wear a hearing aid in one ear due to mid-ear damage, and I'm expecting before long to have an inductive loop for my cell phone that means handsfree use without any kind of additional earpiece. Apart from convincing people that I'm completely mad and talking to myself in the street, it should be a considerable improvement over bluetooth headsets, which, compared to either of my hearing aids, are heavy and have poor frequency response.
Panurge has posted for the last time. Thanks for the positive moderations.
I don't believe that the magnetic fields would need to be so strong that they would cause a problem for magnetic media, but there are probably too many variables to generalize. Think "speakers" here. These generally use magentic coupling too to send information wirelessly (albeit at acoustic frequencies).
Not only can magnets give you lighter wireless communication, but also eternal life!
1 - They complement each other, yes, and they are intimately interrelated.. but they are not the same thing (for practical purposes). If you have a bar magnet in front of you, is their an electric field around it? no, there isn't.
2 - A cruise of the whitepapers indicates that the magnetic field strength is related to distance via 1/d^6, as opposed to radiated power, where it's relatd to 1/d^2. This means a much sharper dropoff in power... meaning the point beyond which there is a negligible power level is much sharper.
3 - A magnetic field and RF radiation are not the same thing.. one transmits energy over distance (RF).. the other puts that energy into sustaining a field (Magnetic)
4 - What you are saying about frequencies applies to RF. This is not about RF. The mention of a high frequency, relatively unused ISM band probably refers to the EM side effects of the devices. (a 10Ghz oscillator, even if it's used via induction, sitll creates a 10Ghz EM signal)
5 - "Used by Industrial, Scientific, and Medical" as they said in the article, is most likely just the reporter trying to sound smart.. but that's usually abbreviated as "ISM", and covers the fun 900Mhz and 2.4Ghz bands we already love and know, as well as others....
6 - interference is not an issue for practical purposes because this thing has a high field strength within the bubble, and virtually none outside. Any inteferer would have to be really strong, or really close.
Now, I'm no physicist, but I was under the impression that all radio waves were based on electromagnetic induction. So this article doesn't really make sense at all.
Now, I know there are some devices that use magnetic induction to 'charge' and then blast out information, like RFID. But the key here is the RF -- radio frequency (ID = identification, of course).
So it would make some sense if these guys said they wanted to carry power using Magnetic induction, rather then using power cables or batteries, but it doesn't make sense for them to say they want to replace 'blue tooth' with it, because blue tooth and all radios use Magnetic induction to communicate...
My guess, yet another reporter with absolutely no idea wft they're talking about.
autopr0n is like, down and stuff.
I really hope you're just trying to be funny and doing a poor job of it, but in case you're serious...
I keep waiting for a gas pump that "recognizes" my gasoline credit card device and waits for me to "fill it up."
Uh, hate to break it to you, but those have been around since the mid to late 90's, when Mobil introduced the SpeedPass. I've had one since long before I ever heard of Bluetooth. Now they are used at Exxon and Mobil stations all over the place. I think McDonald's even did testing a while back in California, IIRC, where people could pay for their drive-thru purchases via SpeedPass-- dunno if that's going to go national. When they launched it, it came in two varieties-- a small cylinder for your keyring that must be waved in front of a spot on the pump, and a transponder meant to be stuck inside your car's window that is "read" by an overhanging antenna when the car first pulls up to the pump (sort of like the E-Z Pass system some states have for toll roads). I think the stick-on transponder SpeedPass has been phased out, because I see no reference to it on the website.
Have a hard time getting a paper receipt, though. Keep getting a message saying "Your receipt is inside."
Where I live, gas pumps have been accepting credit cards right at the pump for at least 10 years, and have been printing their own receipts right at the pump as well. My SpeedPass account is even configured to assume I want a receipt when I gas up, so the pump just spits one out without asking when I'm done filling my tank.
I won't even tell you what I can do with my Macs running OS X and my Bluetooth phone, it may make your head explode. No flying cars yet, though.
I suggest you move to a state where people aren't too busy dating their relatives to embrace technological advances. By the way, the North won.
Correct me if i'm wrong but dont most Radio transmission technologies use some form of magnetic induction in order to achieve their goal. Last i heard passing electricity through a coil produces a magnetic field. Whats new here?
What's new is that they've goofed.
At any given frequency you can launch an electromagnetic wave by using:
- And electric dipole. (Essentially impossible at anything above DC due to the current from the moving charges.)
- A permanent magnet or a current loop (producing a virtual magnetic dipole).
- A combination of the two, to produce the electric and magnetic fields simultaneously.
With a current loop the field very near the loop is essentially pure magnetic and falls off as the first power of distance (as more of the wire's length becomes signficant to the observer).
Moving out a bit more, in the first two the field moderately NEAR the antenna is essentially pure electric or magnetic (respectively) and falls off as a dipole field - with the cube of the distance. (Inverse square for each "pole" of the dipole, times inverse first-power for the smaller angular separation of the poles as viewed by the distant observer.) In the third you get the same effect with both the electric and magnetic field, typical of ordinary antennas.
But the changes to the electric field produce a magnetic field, and vice-versa. By the time you're a wavelength or so away from a simple driven element an electromagnetic field - a "radio wave" - has peeled off. This weakens at inverse-square rate (once you're far enough from the emitter that local additions and cancelations from different parts of it don't confound the issue.)
For signals in the tens of kilohertz and less (audio, for instance), a wavelength is very long. So a coil acts like more like a dipole than an antenna for a long way. Inverse-cube attenuates the signal rapidly with distance (though a strong amplifier can pull it back up - along with any competing noise).
But for computers you'll probably want this to operate at high speed - for images, disk access, etc. Now you're talking megahertz - with coding schemes that end up putting essentially all the informaiton at high frequencies. So the radio-wave effect takes over quickly, and the signal propagates without serious attenuation, regardless of whether the emitter is a magnetic loop (B-field) or electric dipole (E-field) emitter.
The guys operating the TEMPEST equipment will LOVE this system, thanks to the unjustified feeling of security it will give the user.
Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way
N&V covered this in the June 2003 issue along with RFID and UWB. Page 22 for those who can get access to a backissue (say at the library or somewhere like that)
One problem (that's easily fixed) with the magnetic system is that both transmitting and receiving coils have to be parallel. If they're at 90 degrees little or no signal gets through. The fix for it happens to be using 3 coils, each one 90 degrees from each other on the receiver. The transmitter only needs one, but no matter how that one is oriented one of the 3 coils in the receiver can pick it up. I haven't heard of any other chips, but the LibertyLink chip from Aura Communications can automatically select the coils on it's own.
Very short range, but it works for something like a wireless headset where range doesn't matter anyways.
Dear God! I don't think the aluminum foil in my deflector beanie is thick enough to handle all that! Quick, get me some sheet metal!
By contrast, magnetic fields have a very measurable effect on the body. Your blood is composed of about 7-28 umol/L, or if I did the math right, about 1 mg/L. Take a magnet and rub it near a vein sometime. If the field is strong enough, you get reorientation of the red blood cells, and eventually clumping of those cells. In sufficiently concentrated doses, the health effects could be significant.
That's false. Red blood cells do not clump in the presense of magnetic fields.
There have been studies on the phosphene effect, where strong magnetic pulses cause subjects to percieve brief visual images.
Lawrence Livermore National Labs has a page on the harmful effects of very strong magnetic fields, upwards of 40,000 Gauss -- but such fields are rarely encountered. Typical MRI magnetic fields, by comparison, are typically between 5,000 and 20,000 guass. But even in very high static magnetic fields, the effects are temporary.
The big danger is for people with implanted metal, like pace makers or surgical clips.
Now, I did find a study on red blood cells in very strong magnetic fields that does suggest that they reorient, even in fields as low as 10,000 Gauss. No mention of clumping.
Your typical hand-held magnet, even a strong one, produces a field on the order of 4,000 Gauss. Not harmful.
The fields produced by any kind of transmitters mentioned in the article would be tens or hundreds of Gauss -- too weak to move a paperclip.
(The earth's magnetic field is about 0.5 Gauss, for comparison)
On the other hand, the LLNL page mentions that magnetic fields equal to the strength of the Earth's can disrupt circadian rhythm! And it has been proven that birds are sensitive to the Earth's field... so even small magnetic fields can have a measurable biological effect.
But FEAR FEAR FEAR is not warranted.
- Peter
INsigNIFICANT
The data rate is 204.8 kilobits/sec - I can't tell if that's bidirectional or shared unidirectional like Ethernet? However, you're wrong about your use of Nyquist's formula - that tells you that your pulse sampling rate has to be twice the frequency of a continuous wavelength you're trying to send (so your data rate needs to be N*2 samples/sec for a N Hz audio signal). This is the other side - Shannon's formula is that if you want to carry a given bit rate using an analog signal, the bit rate you can get is (IIRC)
Bandwidth * log (1+Signal/Noise)
which means that if your signal/noise ratio is arbitrarily good, you can get an arbitrarily high data rate
The place that Nyquist bites them is that with only a 204.8 kbps data rate, it limits their audio capabilities. They're actually using 64kbps CVSD for their audio, which is kind of an odd choice of codecs - maybe they're sampling at a higher rate than telephony, or maybe they're figuring it will do less or different damage to the signal than the GSM or G.723 codecs used by the phone? In either case, CVSD is a simple codec that doesn't need much CPU horsepower, and a little better than ADPCM at that speed.
Bill Stewart
New Fast-Compression-only CPR http://preview.tinyurl.com/dy575ks
Perhaps the easiest way to explain this technology is that it's simply a type of transformer.
:-)
One coil creates a varying magnetic flux that induces a current in a matching coil -- and thus an electrical signal is passed through the ether.
Those who claim that it's no different to a radio link are almost right -- the only real difference is that with such a system there's no need to use a carrier wave (RF) -- the information can be dumped (raw) into the transmitting side of the coil and received by the other coil.
There's no rocket science here -- all that's happened is that some crowd has figured out that by using three coils instead of one, they can effectively adjust the direction of the strongest flux lobe to give the maximum transfer of energy.
Of course, the marketing droids would never simplify things by simply telling us it was a "clever transformer" because then they couldn't charge so much for it eh?