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NTT DoCoMo's 4G Tests Hit 300Mbps 259
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 (Score:5, Funny)
Not in America it ain't.
Re:Your brand-spankin'-new 3G phone (Score:2)
Phone, agreed.
Broadband... well... more like cable and DSL just became obsolete. I, for one, welcome our new broadband overlords. I can't wait for the day that I can call Comcrap and let them really know how I feel about their pathetically poor service.
Re:Your brand-spankin'-new 3G phone (Score:3, Interesting)
Re:Your brand-spankin'-new 3G phone (Score:3, Funny)
Now I can bring my laptop, set it in the back seat, and say, "email billy bob file Process-Flow-Diagram-02.pdf " and it will work.
Cool.
But aren't we suppsoed to be driving the car. At least for a few more years?
Re:Your brand-spankin'-new 3G phone (Score:2, Insightful)
Re:Your brand-spankin'-new 3G phone (Score:2)
Bandwidth limits suck though... 50MB before it gets really pricey.
Re:Your brand-spankin'-new 3G phone (Score:2)
manifest density (Score:2)
Just what I need... (Score:5, Funny)
"Do the Right Thing. It will gratify some people and astound the rest." - Mark Twain
already have it (Score:2)
their secret is... (Score:5, Funny)
Re:their secret is... (Score:5, Informative)
Actually this is not funny. The United States is, for the most part, sparsely populated compared to most of Europe and Asia. This is why the U.S. carriers hesitated to adopt GSM in the early 90s, which has a fixed number of supported users/frequency and has a maximum cell size due to being time multiplexed. On the other hand, CDMA is able to create much larger cells at the expense of a higher noise floor (hence less users). It was promised to be better suited to sparsely populated areas, yet still tuneable to suit New York City and etc. Whether or not CDMA IS-95 met those goals is debateable.
Japan is indeed under less contraints. Their cell sizes are very small meaning the required transmission power is reduced. If anybody ever saw a Japanese PDC phone from 10 years ago, and was blown away at how small it was, this is the explanation.
Re:their secret is... (Score:5, Informative)
Re:their secret is... (Score:2)
Japan is indeed under less contraints. Their cell sizes are very small meaning the required transmission power is reduced. If anybody ever saw a Japanese PDC phone from 10 years ago, and was blown away at how small it was, this is the explanation.
O.k. all we need to do in this country is figure out how to intergate the base stations into regular lightbulbs and street lights for no extra cost. Then we could all have a unlimited wireless bandwidth anywhere.
Re:their secret is... (Score:2)
Almost a sane idea, except I'm thinking of traffic lights, not street lights -- they either have or need signalling capability to the control center, and they're everywhere. All you need to do is make metropolitan wireless broadband and re-doing traffic lights a high priority.
Re:their secret is... (Score:2)
The bottom line is they have a workforce which is simultaneously very productive - and happy to live in cellblocks no larger than american jails
They are monocultural - which means they do not experience (minority based solutions) they exhibit low rate of population growth,
And which the (minor by comparison) exception of pearl harbor they do not carry a history of sensless genecide.
AIK
Re:their secret is... (Score:4, Insightful)
Re:their secret is... (Score:3, Informative)
The Japanese were fairly brutal during the war.
They killed maybe more than hilter and Stalin - mostly east asians, chinese and Koreans
Nasty.
My Bad
Re:their secret is... (Score:2)
The inmates at Guantanemo Bay are ntitled to whatever protections actually apply.
The Geneva conventions apply to soldiers in uniform - if they were -then they are.
The Constitution applies in various ways.
For example: State actors were not required to recognize the civil rights of persons (usually blacks and women) until the 14 ammendment (circa 1900)
The argument that foriegn nationals on foriegn soil are somehow protected by the Consti
Re:their secret is... (Score:5, Insightful)
Re:their secret is... (Score:3, Funny)
For God's Sake! Would somebody please think of the parents!
Re:their secret is... (Score:5, Funny)
Re:their secret is... (Score:2, Interesting)
Basically, US mobile companies and slow, lazy, inefficient and technologically backwards. They don't want to invest in new technology because they don't have to because
Re:their secret is... (Score:2)
The obvious explanation... (Score:2, Funny)
The obvious explanation for both of these seemingly puzzling questions is of course Pocky.
WSF-OFCDM? (Score:2, Interesting)
Re:WSF-OFCDM? (Score:2, Funny)
Total area to cover (Score:5, Insightful)
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.).
Re:Total area to cover (Score:2)
Re:Total area to cover (Score:2)
There are plenty of places where they've never had the legacy of fully deployed infrastructure like in makor US cities. So in those places, then can go with whatever technology is appropriate, regardless of past investements/oblications in communications tech. As I understand, the phillipines is a great example. They did not have a full buildout of power/comm lines when wireless/cellular came out, so they were able to build out much cheaper and faster using wireless tech. Especially in
Re:Total area to cover (Score:2)
Our Cell phone rates however, are significatly higher then the US and I'm sure else where in the world.
Re:Total area to cover (Score:2)
Re:Total area to cover (Score:2)
It's not that simple. The urban Japanese worker probably spends at least an hour in a train every day, while the urban American might be driving. The urban Japanese living space is much smaller (yes, even compared to a US metropolis), so bulky PCs are not as desirable. Housing costs are also sky-high, which means many people no longer hope to own a
Concentration (Score:2, Interesting)
WiFi Anyone?? (Score:5, Interesting)
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.
What are the power requirements? (Score:2, Interesting)
I guess the only mitigating factor is that you generally won't be using the 4G features with the phone pressed against your head....
Names (Score:5, Informative)
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.
Re:Names (Score:2)
Re:Names (Score:3, Funny)
-fren
Re:Names (Score:3, Funny)
Is it a typo, or maybe it's supposed to be "Wearable spreading factor"? The Japanese phones are pretty small, it's possible they've sewn it into a shirt collar or something?
Re:Names (Score:5, Insightful)
Re:Names (Score:2)
1. Variable spreading factor
2. Orthogonal frequency (division multiplexing)
3. Code division (multiplexing)
Makes a lot of sense to any communications guy when it is named so descriptively (as in, it is informative, not just plain funky)
What it means (Score:2)
That means that they split their frequency allocation into different bands, and then within each band they use Code Division Multiplexing to let multiple systems transmit at the same time.
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).
CDM involves transmitting a large number of bits for each 'real' bit of
Re:What it means (Score:3, Informative)
Are you sure you know what OFDM [wikipedia.org] 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
Population density helps (Score:5, Informative)
Re:Population density helps (Score:2)
Ahem! (Score:5, Funny)
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 [slashdot.org].)
How Japan is "lightyears" ahead of us... (Score:5, Insightful)
--Nerviswreck
Re:How Japan is "lightyears" ahead of us... (Score:2, Interesting)
The country has large cities, but it has 4 large islands that are completely separate. Not to mention the tons of smaller islands and the extreme separation that the different cities have due to mountains.
I think the reason that Japan is light years ahead of us is probably due to the public's desire for this type of technology. Most Japanese use their cell phones for email and web surfing. They want
Re:How Japan is "lightyears" ahead of us... (Score:2)
Even then, you'd have to explain why folks in NYC don't have phones with advanced data services that are still able to work in rural Utah. Population density is certainly one factor, but not the only factor at all. For example, most ur
Re:How Japan is "lightyears" ahead of us... (Score:3, Funny)
And then there's the fact that we are still so busy over here trying to monetize email and instant messaging that the wireless train left the station without us.
Because Cell phones weren't distracting enough (Score:5, Funny)
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!
Re:Because Cell phones weren't distracting enough (Score:2)
Bandwidth (Score:3, Funny)
So let's see... (Score:5, Funny)
That means that they got....let's see....carry the one...
135Mb of data through before the battery ran out.
Pretty good.
WSF-OFCDM? (Score:2, Funny)
Simple (Score:2)
Yes Yes.. (Score:3, Interesting)
Re:Yes Yes.. (Score:2)
Yes. The kid with Kazaa will be soaking up all the bandwidth in the cell, so you won't be able to make a call in the first place.
Am I the only one that is worried? (Score:2)
These days we have problems with people talking on the cell phone while driving. With this bandwidth and video capabilities how soon before we have people watching pr0n and driving? Gives new meaning to the term "spill-over"
Re:Am I the only one that is worried? (Score:2)
why Japan is lightyears ahead is... (Score:5, Insightful)
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...
How do they do it? (Score:3, Funny)
Can't tell you how, but why is obvious... You can't run cable through paper walls...
Rehtorical question? (Score:5, Informative)
Might have something to do with the fact that they have 130 Million people in an area slightly smaller than california [worldfactsandfigures.com].
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.
Japan is not that large... (Score:2, Insightful)
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.
Simple, they want the best, we want the values. (Score:5, Interesting)
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.
Re:Simple, they want the best, we want the values. (Score:3, Insightful)
My GSM phone is going on 7 years old. I keep it because it is a mobile telephone, which works well and has a standby time of about 3 weeks or talk time of about 8 hours. Until I find a phone I can rely on to keep me contactable all day almost guaranteed or until it breaks, I will keep it.
I don't ever want to go back to the days of having a mobile that cuts out before the business day is over and I'm nowhere
Let me guess... (Score:2)
Great. (Score:2, Funny)
I'll be happy if I can just get a working basic connection in the Bay Area (thanks so much, AT&T).
E-mail me if you want to start a REAL wireless ISP (Score:2)
300Mbit per sec to anywhere near a tower we can get on????
I kid you not. We could rule the world...until we get bought out.
Not spamming, FYI. (Score:2)
Licensed technology. Real throughput. Cheap bandwidth abound to link it to.....ah, a network engineer's dream. And nightmare.
few cooks = faster innovation (Score:2)
Why do you think we have so many different cellular technologies here in the states...most of them aren't compatible with each other?
We just need to standardize and streamline (especially the FCC procedures) our wireless so we can get 300Mbps.
Also, Japanese wireless companies don't try to keep old technology active to milk money off of it; instead they c
Re:few cooks = faster innovation (Score:2)
that depends on you ask.
Also, the Japanese have also invested in digital HDTV as well as analog so there will be SOME backward compatibility (in existing satellites; but that was only until they launched the newer digital satellites to replace the old ones).
Also, TDMA is used by AT&T. (GSM is a TDMA based tech). And the Japanese companies adopted CDMA and CDMA based technology (including 3G) alot faster (and in some cases before) than US companies.
Another example of the US's unwillin
Lightyears ahead of everyone... (Score:4, Funny)
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.
Now I can (Score:2)
Even Better, in UT2k3, I can drive the vehicles. Uhh ohh watch out for that RL, left turn----crash....bang, whoops I meant left arrow, sorry officer.
As if cell phone distractions weren't bad enough.
Answers (Requiring thougth :) (Score:2)
A very densely populated country, with concentrated cities that allow a high level of money return for every repeater installed. Also, more repeaters imply less distance to the possible target, which allows for more data troughoutput^H^H^H^H^H^H^H^H^H^H^H^Hspeed. A gadget-loving population also helps.
Who comes up with these names?
Uh? That should be self-evident^H^H^H^H^H^H^H^H^H^H^H^Hobvious. Committees, of course.
(revised
Huh (Score:2)
Is that like multi-modal reflection sorting? (link [216.239.51.104])
Cool name (Score:2)
Wow, that's the coolest name ever...
Note: Requires L-O-S to the base station... (Score:3, Informative)
Density of wealth amongst populace (Score:5, Interesting)
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.
As someone who worked with NTT.. (Score:3, Informative)
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.
Well (Score:3, Insightful)
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.
It's all about the work ethic. (Score:2)
Of course, our Generals have to report to the pen
Lightyears Not! (Score:2)
One working example on one day does not put them lightyears ahead of anyone. An installed, working system that people can use -- and afford -- might.
Who and how? (Score:2)
I came up with the name!! Why? What's wrong with it? You should have seen the Engrish [engrish.com] they came up with the first time around!
And to answer the "How" question, the answer is simple! Smaller cost of roll-out, fewer zoning regulations (do they even KNOW what zoning is in Japan?) and a high-rate of initial adopters all spells a quick update of technology on their island nation.
Lets not forget... (Score:2)
There are no technical specifications for the time being, nothing concrete.
There's no guarantee that NTT's 4G will be the chosen 4G implementation, neither is any guarantee that NTT's implementation shall be the one to gain the biggest market share (see the FDD and TDD UMTS modes and just when a compromise was reached, China come up with their own system...)
Your variable spreading factor style is nothing! (Score:2)
I hear this is really only a placeholder to the followup technology, SUPER MEGA ULTRA HYPER-variable spreading factor orthogonal frequency code division multiplexing COMBO RAVE, ULTIMATE TOURNAMENT EDITION (SMUH-WSF-OFCDM-CR,UTE) downstream technology.
Just a rumor. I work for Nintendo you know. In Japan. I have connections to this sort of thing.
What VS-OFCDM is (Score:3, Informative)
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 [chalmers.se] and this paper [kcl.ac.uk] gives some background.
VS-OFCDM changes the spreading factor adaptively based on cell structure, channel load, radio link conditions, etc.
DoS (Score:2, Interesting)
Shared bandwidth? (Score:2)
Just like 802.11b -- where throughput drops proportionally to the number of active users.
-Charles
VSF (Score:2)
I found a good PDF Presentation [kcl.ac.uk] from NTT DoCoMo explaining in detail VSF-OFCDM. Of interest is its use of Turbo codes for the channel encoding (Turbo codes were mentioned in a previous Slashdot story [slashdot.org]), and that the uplink bandwidth of the system is 40MHz versus the downlink bandwidth of 101.5MHz. Very interesting stuff!
Wow cool name... (Score:2)
"A variable spreading factor orthogonal frequency code division multiplexing downstream device."
"Wow... does that come with an optical mouse ?"
Can't wait to gloat
Wariable? (Score:2)
I guess they must spell variable wariable.
So When Exactly (Score:2)
magic numbers? (Score:3, Interesting)
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.
Re:magic numbers? (Score:4, Informative)
Hmm. Perhaps you should consider the technology name. Much like the old quadrature based encodings, the orthogonal nature of the encoding will permit multiple bits per cycle. Othogonal carriers would be independent of one another, and therefore, be something that could be sampled independently.
Do not confuse what Nyquist has to say about sampling a single signal with the numbers presented. Each orthogonal component is a new axis upon which they can mux a data carrier (in the simplest sense).
Re:magic numbers? (Score:3, Informative)
Shannon's Law states the maximum error free digital bandwidth b bits/s of an a slice of spectrum c Hz wide is:
b = c.log2(1+s)
Where s is the signal-to-noise ratio. Thus, in this case, where b=300000000 and c=100000000 s = 7, or 8.5dB, not an unrealistic expectation.
Of course, no current form of error correction coding approaches the ideal Shannon's Law, however reasonably recently developed Turbo Codes [unisa.edu.au] have come reasonably close.
The sort
Re:Day in the life of a Liberal [Otto] (Score:2, Funny)
I think this is a description of a painting by Hieronymus Bosch...
Re:Eat that DSL and Cable (Score:3, Funny)
Doppler (Score:3, Interesting)
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.