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Wireless Video Transfers 100X Faster Than WiFi
coondoggie writes "Later today IBM plans to announce microprocessor chipsets that can wirelessly transmit high-definition video at extremely high speeds. 'IBM will do this by teaming with MediaTek to launch a joint initiative to develop these ultra fast chipsets.The companies will be developing millimeter wave (mmWave) radio technology — the highest frequency portion of the radio spectrum — 60 gigahertz rather than 2.4 gigahertz — and digital chipsets that enable at least 100 times higher data rates than current Wi-Fi standards.'"
Article is shithouse - light on detail beyond belief. Check out IBM's 60GHz page.
What you want to know: Practical limitation is 10M, useless through walls.
There are shills on slashdot. Apparently, I'm one of them.
Is this different from the previously reported military use of millimeter wave in anything other than power? If so, what are the dangers, or is it supposedly safe?
Wireless Video Transfers 100X Faster Than WiFi
Philo Farnsworth called the technology Image Dissection. I hear they get pretty bitchin' range with it too. AFAIK it now also handles HD content.
I like music
At that frequency, the signal wouldn't penetrate PAPER very well. You can think of it (nearly correctly) as a very weak flashlight beam, much like a regular old TV remote. Only lots more picky about everything being just right.
To boldly use to and too two times and get it right too! They're not gonna believe their eyes when they see it there!
I'm betting its useless through walls since 802.11a uses 5GHz band and it very reliant on line of sight (you might be able to put it through a single wall). There are good reasons to use these though like if you want to limit your WiFi to the inside of a building and such it might limit the range to an acceptable level outside where someone passing by on the road wont be able to pick up a wireless signal. Likewise using these ultra high frequency ranges may make it impossible for it to pass outside the house which would effectively be good if you wanted to design a system that neighbors could not catch what you're watching on their TV.
The thing is from what I understand is that in order to get data from A to B more quickly you either need A) Multiple bands/More Bandwidth or B) Higher Frequency because you can switch states faster.
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+2 Troll is Slashdot's way of saying groupthink is confused
Since Wi-Fi is generally 11-54 mbit they're only talking 1-5 gbit. The mentioned use is for video so it sounds like they are trying to connect displays to devices that generate output, i.e. replacing a monitor cable. For comparison DVI is 3.7 gbit, DVI-D 7.4. Most likely they are talking about the 1-2 gbit range since if it was in the 5gbit range they'd probably have said so instead of 100x wifi. That data rate would only be useful for low-resolution displays like HDTVs, not for general purpose computer monitor use. The devices would likely need to be close to each other due to the high frequencies. It sounds like they may be targeting removing the cable requirements home theater systems or something similar.
Personally.. I like cables for hooking up video. Wireless is buggy, snoopable, power hungry, and hard to set up (with 4 transmitters and 4 receivers, how to you configure what displays where?) Cables, while bulky and sometimes annoying have an incredibly easy UI. Plug one end here, the other end there, the things are connected. Want to change it? plug the wire in somewhere else.
set softtabstop=4 shiftwidth=4 expandtab nocp worlddomination
I would modify that slightly by saying 60GHz will travel through a typical office partition (with attenuation), so it's slightly better than line of sight (ie. infrared). Bricks walls are out, you might get away with a plasterboard wall. You probably can put a 60GHz access point on the ceiling of an open plan office and get a useful signal to each desk through a combination of propagation through light partitions, reflection and directional antennas. It will save having to wire an open plan office with ethernet. I know this because I was involved in a 60GHz project, that included a propagation study, in 1995. Google for the paper "A HIGH-SPEED WIRELESS LAN", IEEE Micro, 1997.
Perhaps. As you have pointed out, MIMO relies on a "rich" multipath channel with lots of reflectors. Above 10GHz the channel starts to move towards ray propagation, reducing the amount of multipath in the channel. This might reduce the effectiveness of MIMO. I said "perhaps" because an open plan office might be a special case due to the sheer number of metallic reflectors in range. I gather some research groups are performing the relevant channel measurements, but I haven't seen the results.
Neither one of those links could be considered source material for the harmful effects of this sort of tecnology. The first one reports on increased cancers at the site where RFID chips are implanted. It's not about exposure to radio energy so much as it is about having a radio receiver implanted in the body. The second one doesn't offer up any facts related to the harmfulness of wireless technology. It's purely a specultative 'what if fluff' piece. Got anything better?
Hence, you put a slim, shielded tube over the distance you want to transfer. At each end of the tube is a transmitter/receiver. With further research it might even be possible to bend these tubes, so they go around corners etc. This would solve all the problems identified.
This tube has a name and has been in existance for many years. It's called a waveguide.
http://en.wikipedia.org/wiki/Waveguide
http://www.microwaves101.com/encyclopedia/waveguide.cfm
Drawings of some waveguides are here;
http://www.uniquesys.com/products/passive/waveguides/s111_2.html?gclid=COyF1u6coo8CFSI4YAod20h_aQ
You can buy eliptical waveguide here for frequencies up to about 22 GHZ.
http://antennasystems.com/ewassy.html
and rectangular waveguide up to 40 GHZ here.
http://www.antennasystems.com/waveguide.html
The truth shall set you free!
You're right that frequency and power are different. Mutations require ionizing radiation; basically alpha/beta/gamma rays, neutrons, cosmic rays, etc. Well into the ultraviolet is about the lowest frequency that can be mutationally dangerous - somewhere around 10E-8 m, or thousands of times higher frequency than millimeter wave RF.
All millimeter wave RF can do is heat objects. It can do this promptly and well below the surface. With enough power, it can kill you pretty quickly by simple heating, but that's all. With a well focused beam, your brain could be literally cooked basically before you notice it. But practically speaking there is no intensity or duration of microwaves that causes mutations.
Sort of. Higher frequencies mean more energy in each photon. True. At some point the energy in a photon is sufficient to break up complex molecules, true. Molecules being destroyed in your body include the risk of DNA or other important molecules in your cells suffering damage, which leads to increased cancer-risk. True.
BUT, and this is a large BUT, the frequency of where this happens is a long way away from mm-wave, and fairly well-known.
We bathe in this thing called visible light every day. Visible light has a wavelength of around 400 to 800 nanometres, which is to say 400 to 800 billionths of a metre. 1 mm is a *thousandth* of a metre, so we're talking 6 orders of magnitude lower frequencies.
Once we get below 400nm damages start happening, most know that UV-light will increase the risk of skin-cancer, even higher frequencies such as x-rays will cause cancers generally, and not just in the skin since they're ionising *and* more penetrating that UV-light is.
Short answer: ir-wave radio is MUCH too low frequency to even start getting close to ionising.
There does seem to be a valley at 60 GHz according to this chart
Man who leaps off cliff jumps to conclusion.