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NTT DoCoMo's 4G Tests Hit 300Mbps
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?"
'Your brand-spankin'-new 3G phone is nearing obsolesence:'
Not in America it ain't.
"Draco dormiens nunquam titillandus."
A cell phone that's equivalent to 87.66234 T-1 lines..
"Do the Right Thing. It will gratify some people and astound the rest." - Mark Twain
"Do the Right Thing. It will gratify some people and astound the rest." - Mark Twain
...that it's a very small island, just put big transmitters on mountantops and you're good to go
Who comes up with these names, and how does Japan manage to stay lightyears ahead of everyone else in wireless?
The obvious explanation for both of these seemingly puzzling questions is of course Pocky.
--Kevin
I don't speak Japanese, but shouldn't the acronym for ariable spreading factor orthogonal frequency code division multiplexing be VSF-OFCDM?
Simple, smaller area to provide coverage = lower cost. That's why in places like South Korea you can get a LOT of bandwith a whole lot cheaper than here (U.S.).
Might it be partially due to the higher concentration of people? Because the Japanese people live in closer proximity to one another, fewer cell-towers are needed to provide coverage for a comparable amount of people. Therefore, each cell tower can he of higher quality.
An effective signature identifies a particular user amongst a base of thousands.
After reading this article - it has led me to analyze the benefits of this versus traditional 802.11x and the application of 4G in the broadband arena.
:)
At a proposed sustained rate of 1G, this technology could revolutionize the Internet as we know it today. And, with more and more bandwidth readily available, there will be better multiplayer games online, as well as streaming on-demand cable-like tv off the Net.
I understand that the technology is proposed for gadgets such as a phone or wristwatch that can also watch HDTV - but imagine a world where everyone has a video-phone conference & everyone also has a 1G up/down broadband connection
In a word - WOW.
Who comes up with these names...
Assuming the poster is referring to ``variable spreading factor orthogonal frequency code division multiplexing (WSF-OFCDM) downstream technology'', the name describes exactly how the technology works. Without reading a technical paper on the technology, I don't know the exact details, but I know what it is doing and what it isn't doing.
(S(SKK)(SKK))(S(SKK)(SKK))
their new variable spreading factor orthogonal frequency code division multiplexing (WSF-OFCDM) downstream technology
This is a lie!
I had nothing to do with this!
(And I don't do variable spreading of my factor. And certainly not in a car going 35 mph.)
(Ok, now that you've laughed at me, "Vote" in my unofficial presidential poll.)
Opinions on the Twiddler2 hand-held keyboard?
Japan is small, The US is huge. Converting the entire japanese network is a meager task compared to converting the entire US network, or even in all the major cities in the US.
--Nerviswreck
Now we can drive with one knee, eat with one hand and watch /.-The Movie at 90mph.
There is a race in technology : Things That Distract Drivers vs Things That Replace Drivers (TTDDvTTRD). If automatic nav doesn't catch up, we will all be victims of our own entertainment.
Cheers!
www.olin.edu
That's all very nice, but the real question is: what's the bandiwdth of a station wagon full of telephones barrelling down the highway?
How can we continue to believe in a just universe and freedom to eat crackers if we have no ale?
That means that they got....let's see....carry the one...
135Mb of data through before the battery ran out.
Pretty good.
"If you want to improve, be content to be thought foolish and stupid." - Epictetus
You sure it's not WTF-OFCDM?
High speed data is fantastic..but will it prevent me from having dropped calls?
So many injustices..so little time..
because the alternative they have, which is to rewire the humongous buildings that they have in the very limited amount of space available.
Same story with Chine from a different perspective. Wiring the old buildings for phone communications is not feasible fianncially.
At the end, when alternative is very expensive, people tend to be more creative than what is expected of them. Can be applied to anything, not only wireless or technology...
__________
The more I know people, the more I love animals
how does Japan manage to stay lightyears ahead of everyone else in wireless?
Can't tell you how, but why is obvious... You can't run cable through paper walls...
how does Japan manage to stay lightyears ahead of everyone else in wireless?
Might have something to do with the fact that they have 130 Million people in an area slightly smaller than california.
Lot less area to provide coverage for. Not to mention 26 million people in Tokyo alone, making it the highest density city on the planet.
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how does Japan manage to stay lightyears ahead of everyone else in wireless?
Because Japan is densely populated on a mall landmass, it's not such a logistical nightmare to have almost all the area covered by high end wireless service. It also can offer a quick market turnaround and a stepping stone into the greater world market.
this is my sig, be amazed.
From what I understand (never been to Japan), everyone wants the best coolest *insert random item here*. People will upgrade their phones and other gadgets every month, and get rid of their old ones.
In the US (live in US so cant say the same about other countries), yes people will buy the latest greatest, but will keep it for years, how many people do you know that have cellphones that are 2-3 years old.
People will only upgrade when their gadgets break, or a new technology comes out they really need. so new phones come out slower, and cheaper (cheap = break easy).
No point in rushing out the newest greatest items when people will allways wait.
TruePunk | Games
Yeah, 135 Mbps would prove great for full motion streaming video, but how good will all that porn look on a 1" LCD?
One more feature that will be over-sold and over-priced when it reaches the States.
I'll be happy if I can just get a working basic connection in the Bay Area (thanks so much, AT&T).
Is speeding up like moving farther from your phone company's CO and using DSL? (slower speed)
The faster you are going means the Doppler effect is more pronounced. Wide Doppler ranges can be a pain to deal with in the receiver.
(S(SKK)(SKK))(S(SKK)(SKK))
how does Japan manage to stay lightyears ahead of everyone else in wireless?
By protecting their secrets with giant anime robots.
Either that, or they found some ancient, advanced, lost wireless technology and got a patent on it.
It would be nice to mention that before the furor erupts...
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More specifically, financial density. Japan is the world's second biggest economy, with an economy roughly half that of the US, or three times bigger than the UK, but with only double the population of the UK. Money is also more equally spread between the rich and poor in Japan. This leads to a relatively high monetary density country-wide, meaning lots of people who can afford high-end services.
This would explain why other densely populated counties, like Bangladesh, aren't riding high on the wagon.. it's because Japan is rich, has wealth more fairly disitributed, and has a dense population. Scandinavia also has its wealth more fairly spread between its citizens, and also boasts some of the world's most impressive mass technologies.
NTT is a surprisingly large company (now a group of companies), and the bureaucracy of such a company is staggeringly prohibitive to actually getting anything accomplished.
We tried launching Wireless access there in 2000 and 2001, and the endless meetings and forms were more than discouraging.
But the real answer to how NTT DoCoMo (a division of the monster) manages to turn around so fast is that their researchers work with cell researchers from KDDI, J-Phone (now Vodafone), and that other one who nobody uses (TUCA).
Where does all the funding for research come from? Well, in a country of now 135 million people, there are over 80 million cellular subscribers. A good portion of these are also cellular internet users, paying an extra 100 yen here, 100 yen there for different services.
There is a LOT more income on a monthly basis to Japanese cellular providers than there is in America, or anywhere else in the world.
The easy bottom line is that all this cash can be thrown at research, and that this research is further supported by companies like National/Panasonic, Toshiba, Sony, etc who make the phones for Japan.
The average turn-around time in phone ownership in Japan is 9 months. Your $150 top-of-the-line video-camera/mp3/digital still camera/phone is made obsolete in that short span of time. The furthering of technology by DoCoMo/Vodaphone/etc allows the phone manufacturers to move more units.
The consumer gets new features at the same monthly price (more or less), a new phone to show off to friends, and better service.
The providers and hardware manufacturers rake in the cash.
The cycle supports itself, and it makes everyone happy.
Only those who attempt the absurd will achieve the impossible.
how does Japan manage to stay lightyears ahead of everyone else in wireless?
Maybe they don't have risk-averse, office-politics-obsessed middle managers more interested in shitting all over other people's careers than actually building something useful?
Maybe they have found a way to put capital to work employing people and building new products instead of sitting around a table whining that they might fail.
First it was cars, then electronics, now animation. So Japan is kicking our ass again? Well boo-fuckin-hoo.
Business isn't willing to pay for products, innovation and careers, so we get brands, mortgage commercials and layoffs.
VS-OFCDM (variable spreading factor orthogonal frequency AND code division multiplexing) is a special case of MC-CDMA (multi-carrier CDMA).
CDMA has lots of advantages for ease of frequency-reuse, as you can have a lot of people on the same frequency, but each one spread with different codes.
OFDM has a lot of resistance against fading (i.e. signal going in and out as you move through diffracted and relected signal peaks and valleys), because you are putting out your signal on a wide range of frequencies. You also get additional frequency diversity from OFDM.
Put them together by doing CDMA spreading first and OFDMing the result, and as much like in the combination of peanut butter and chocolate that results in peanut butter cups, you get an excellent result!
This paper and this paper gives some background.
VS-OFCDM changes the spreading factor adaptively based on cell structure, channel load, radio link conditions, etc.
I don't keep up much on mobile phone tech. so this is probably nothing new but with this kind of speed are we likely to see trojaned phones contributing to Spam remailing and DDoS when they start spreading to the masses and incorporating more user friendly software (read exploit friendly)?
"The company said that the test achieved a maximum downstream data rate of 300Mbps ...
The frequency bandwidth[s] for the test [are] 100MHz..."
How do they get 3bits per cycle? Nyquist frequency limits mean 100MHz could optimally carry 50Mbps, not 6 times that in an actual test.
--
make install -not war
What you really need to look for in radio technology is spectral efficiency or bits per hertz per second. When you do the math this isn't that great of a technology, it just uses big channels.
Orthoganal seems superfluous to me - Essentially it says that the code patterns will be chosen so that no two transmitters overlap (for lack of a better laymans explanation).
Are you sure you know what OFDM is? It basically involves overlapping signals on a series of overlapping frequencies, but with different intensities at different frequencies. And each channels set of intensities is orthagonal to each other. Which makes the 'O' decidely non-redundant, as this is hardly traditional FDMA. Think of it as CDMA peformed on an FFT.
Your description of CDMA left a little to be desired as well, but its hard to express laymanwise, I agree.