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Experimental 4G Phone Service Faster Than Cable
JymBrittain writes "NewScientist reports that Japanese researchers have achieved blistering rates of transmission for cell phones that allowed for viewing of 32 high definition video streams, while traveling in an automobile at 20 kilometers per hour. From the article: "Officials from NTT DoCoMo say the phones could receive data at 100 megabits per second on the move and at up to a gigabit per second while static. At this rate, an entire DVD could be downloaded within a minute." These transmission rates were achieved using new experimental methods of multiplexing."
if your device has enough memory to hold it and is fast enough cpu-wise to sustain a decent gbit pipe.
:)
Regular consumer pc having drives fast enough to get a dvd in a minute? Good thing we nerds get to the good stuff before anyone else.
1. Why do they keep adding all these new features? I just want a plain phone.
Get a Vodafone Simply and go read People magazine instead of slashdot.
2. Yeah, that's great and all, but when do we get this for our laptops?
The same time we get it for our phones. While irda and bluetooth can't handle these kinds of rates, usb, wireless usb or the next generation connection interface will. (4G is still years and years away)
Also, I seem to remember that one part of the multiplexing ideas for 4G was too use differently oriented antennas, dynamically adapting a signal mixing scheme to filter out the signal minus most interferences and echos, as those shouldn't be uniform for different polarizations. Therefore, saying that there simply can't be enough available bandwidth in the air isn't that relevant. We are still far from the theoretical maximums, and this kind of approach also opens the possibility of nearby transmitters sharing the same frequency with less jamming. Sure, these numbers might be optimistic, but if proper multiplexing gets into the standard, 4G will be far more interesting from a technological standpoint than 3G. Did I mention lower transmission power? (at least when not maxing the connection)
I am sick of these optimistic figures (to put it mildly).
It is fine for 1 cellphone to receive 100Mbps.
But how does it scale? Remember, there will be about 10000 users within range of a base. Can the base pump out 1Tbps of data? (Remember, the users could be watching live HD video at the same time).
NTT DoCoMo's 4G Tests Hit 300Mbps
Posted by CmdrTaco on 06:55 AM June 2nd, 2004
from the and-i-still-can't-get-cable dept.
haunebu writes "'Your brand-spankin'-new 3G phone is nearing obsolesence: NTT DoCoMo reveals the results from a new 4G test system.' says TheFeature. While in a car moving at 30kph, DoCoMo engineers managed a peak throughput of 300Mbps and a sustained transfer rate of 135Mbps with their new variable spreading factor orthogonal frequency code division multiplexing (WSF-OFCDM) downstream technology. Who comes up with these names, and how does Japan manage to stay lightyears ahead of everyone else in wireless?"
Given that you could get a 50mbps DSL connection for less than $40/month in Japan, I would assume not much.
:)
:)
Hey now. Some parts of the US aren't quite as far behind as others
For example, in my city they are just finishing installation of a citywide fiber network. Very freaking awesome, but what's better is that I can get (and am going to) an amazing Internet connection. For $40/mo I get 20Mbps download and upload with a public IP. That's right, $40/mo, and when I asked about running my own server they said, "That's fine, just don't host anything illegal." Double that and you get unlimited local and long distance VoIP and local cable in addition to 20Mbps Internet.
See? Fiber really is good for you!
"What do you despise? By this are you truly known." --Princess Irulan, Manual of Muad'Dib
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2) It heavily depends on the protocol on top of the multiplexing: 3G allows high bandwidth, because a single phone can be served by multiple base stations (=masts). However, as we already saw with GPRS and WAP, if the protocol is bad (voice had more priority than data packets; hand overs between base stations could not treat data connections very well too), the whole service will die (=no more WAP).
3) It heavily depends of the number of cell phones per cell. All these test drives show the optimal case (just remember that 3G promised 384 kBit/s, but if you are in a car, you have only less than 100 kb/s left). Data has (an probabily will still have) less priority than voice calls. So your porn download will be stalling, because your neighbour has phone sex ;-)
4) Who really needs that stuff? My country is one of the no 1 test markets in the world (a target market of 6 Mio people and 5 mobile telephony providers!!), we have a lot of different services, phoning is almost free of charge. Virtually nobody uses 3G now, everybody uses the phone for voice connections and short messages. Only a very small number uses the phone for data connections (btw. also multi-media short messages did not catch on yet).
However
Japan is different. When NTT Docomo get in the market, land line internet access was very expensive. Many people used the phone as primary private internet access. That's one reason for the huge success. (Though I, and also the available surveys about that topic, don't understand, why people in Japan pay that much money for phone screen savers ;-)
DOCSIS 3 will use a channel bonding technique to achieve similiar speeds through coaxial. Essentially by reclaiming analog channel space by converting to all digital systems (I'm beta testing this right now) in the next 3 years that same analog space can be phased out giving back all the waste channel space without needing upgrade the cable system itself to support higher frequencies. What this basically does in layman terms is instead of sending all the data across the same frequency it breaks the data up across multiple frequencies in parallel.
Something to the effect of:
Old
699Mhz 11111111
New
699Mhz 1
689Mhz 1
679Mhz 1
669Mhz 1
659Mhz 1
649Mhz 1
639Mhz 1
629Mhz 1
It probably will take 6mhz, not 10mhz but by allowing some space between the carriers it avoids some noise between them.
This experiment shows 4G will be kick ass in terms of bandwidth, but unless DoCoMo has plans to develop some revolutionary display technology I can't see myself upgrading from 3G.
Keitai displays are too small for this to be useful in the mobile phone market - but maybe that not what they are aiming for?
Was the transmission aerial/basestation moving to follow the car? Why is it relevant?
(I know a few years ago I had a lecture from a telecoms guy who mentioned moving aerials for 3G etc, but I didn't realise they were ready to be used)
DG
The Ginger Dog
40$/Mo ? Here in Europe (france) I get my internet access for only 30Eur/Mo (~30$), speed=20MBits/s (ADSL2+), free local&long distance calls, wifi router plus free cable tv included.