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Wireless Networking Hardware

NTT DoCoMo's 4G Tests Hit 300Mbps 259

Posted by CmdrTaco
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?"
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NTT DoCoMo's 4G Tests Hit 300Mbps

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  • 'Your brand-spankin'-new 3G phone is nearing obsolesence:'

    Not in America it ain't.

    • Not in America it ain't.

      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.
      • Once I get a few things out of the way (a wedding, for one), I'm going to work with my township to provide fiber-to-the-home service. The electrical and sewer systems need replaced, so this is a perfect time to future-proof our infrastructure while providing incentives for businesses to move here and services for people. Then I can tell Comcast to suck it, like I've been wanting to do for a long, long time.
      • Considering some new cars have a bluetooth integration with the car audio system and cell phones. You sit in yo car, drive arround, say "call billy bob" and the thing rings, through the cell phone in your pocket.

        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? :)
    • Seriously. Has anyone seen an actual 3G network yet? GSM/GPRS speeds are still like dialup, but with a latency that makes you yearn for your dialup connection. CDMA stuff (like PCS Vision) is faster and has acceptable latency, but still, 100K or so really isn't great. I've heard the term 2.5G thrown around, but wireless internet is still no great shakes as far as I can see.
      • I get 384k 3G speeds on my laptop with no trouble in the UK.

        Bandwidth limits suck though... 50MB before it gets really pricey.
      • A paper [yorku.ca] I wrote about 1.5 years ago, entitled, "Evolution towards 3G Technologies and Beyond" may be of interest to some of you.
  • by the_rajah (749499) on Tuesday June 01, 2004 @01:57PM (#9306386) Homepage
    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
  • by Digitus1337 (671442) <lk_digitus AT hotmail DOT com> on Tuesday June 01, 2004 @01:58PM (#9306396) Homepage
    ...that it's a very small island, just put big transmitters on mountantops and you're good to go
    • by mrm677 (456727) on Tuesday June 01, 2004 @02:09PM (#9306582)
      ...that it's a very small island, just put big transmitters on mountantops and you're good to go

      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.
      • by brianjcain (622084) on Tuesday June 01, 2004 @02:28PM (#9306837) Journal
        Motorola's GSM base stations offer extended range cells (120km radius) which do implement the coverage density/cell size tradeoff you describe. I'd imagine it might be easier for CDMA to offer a larger set of grades than these do, though.

      • 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.
        • 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.

          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.
      • Yeah -
        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

        • by Anonymous Coward on Tuesday June 01, 2004 @02:55PM (#9307265)
          And which the (minor by comparison) exception of pearl harbor they do not carry a history of sensless genecide.
          You have got to be kidding. Americans are so fucking ignorant about world history it makes me weep.
          • yeah - AC has a point (perhaps 2) here.

            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
      • by kryonD (163018) on Tuesday June 01, 2004 @02:52PM (#9307218) Homepage Journal
        Actually, we are waging a cultural battle that we are never going to win. Most of my friends in Tokyo who are in their 20's and still not married still live with their parents. And they average about 60K in income. Stop and think for a second how many toys you could buy for that kind of cash at the expense of still living with your parents. No place to make out with your girlfriend (I know this is slashdot, but work with me on this...), no problem, just go to a love hotel with the waterfall themed room and only pay $30 for 3 hours of sweet loving. Yes, eventually you'll get married and get a place of your own and be back in the poor house, but by then your tired of having the bleeding edge in fashion and tech and are just happy with something that works. No hurt to the economy as there is a generation of youngsters rolling almost their entire bank into having cell phones that double as credit cards/train tickets/PDAs/TVs/Digital Cameras/Radio telescopes. Just imagine if every young american was buying a new cell phone on an average of every 6 to 12 months....the companies would be forced to innovate to give us something better than we bought 6 months ago or lose us to a competitor who say, already is developing wotking 4G technology.
        • Most of my friends in Tokyo who are in their 20's and still not married still live with their parents

          For God's Sake! Would somebody please think of the parents!
    • by Anonymous Coward on Tuesday June 01, 2004 @02:10PM (#9306598)
      Yeah, but when a giant lizard (who shall remain nameless) tears down those transmitters every couple of years and they have to be put back up, thats when you see how resourceful the Japanese truely are.
    • by minairia (608427)
      This still doesn't answer why the US is so backwards in mobile. There's no reason why we couldn't have Japanese style mobile networks in the US in dense areas like Florida, New York or Chicago and just expand them out to the less populated areas as time goes on. (Even in Japan, in the far outlying areas, there are places without coverage).

      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

    • Actually, their secret is investment in emerging technology. Throw billions of dollars at a problem, and it usually goes away.
  • 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.
  • WSF-OFCDM? (Score:2, Interesting)

    by FreeHeel (620639)
    I don't speak Japanese, but shouldn't the acronym for ariable spreading factor orthogonal frequency code division multiplexing be VSF-OFCDM?
    • by Anonymous Coward
      valiable spleading factol olthogonal flequency...
  • by Fiz Ocelot (642698) <baelzharon@NoSPAm.gmail.com> on Tuesday June 01, 2004 @01:58PM (#9306409)
    "how does Japan manage to stay lightyears ahead of everyone else in wireless?"

    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.).

    • So how come we don't see similar bandwidth numbers in large American cities like New York or LA? They're very dense and have a miniscule physical area compared to the rest of the country, a market of 7 million+ potential subscribers, and yet until quite recently you couldn't even get cable internet in NYC!

      • Call it leapfrogging,

        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
    • I'm not quite sure smaller area translates to cheaper access. In Canada you pay 44.95/month for 5mbps/800kbps cable connection, which afaik is much cheaper then the US and we're about 100 times the size of S. Korea.
      Our Cell phone rates however, are significatly higher then the US and I'm sure else where in the world.
      • That's a little cheaper (since the Canadian dollar is a little less) but not much different. Here it's $40USD/month and offers speeds of at least 5mbps down (not sure what the actual cap is). Of course, like all cable, it's consumer level and contingent on how loaded your segment is. Consumer level broadband is getting pretty cheap, it's the pro stuff that tends to be expensive.
    • 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.).

      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)

    by jm92956n (758515)
    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.
  • WiFi Anyone?? (Score:5, Interesting)

    by dukeluke (712001) * <dukeluke16@hotMO ... om minus painter> on Tuesday June 01, 2004 @01:59PM (#9306418) Journal
    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.
  • Does this need more power? I'm afraid as it is about using cell phones so close to my head (Richard Brandon, owner of Virgin refused to use a cell phone without a headset, and he has done stupider things like trying to balloon around the world!).

    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)

    by bsd4me (759597) on Tuesday June 01, 2004 @01:59PM (#9306428)

    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.

    • Well then why isn't it VSF-OFCDM?
    • Re:Names (Score:3, Funny)

      by Tenebrious1 (530949)
      ...variable spreading factor ... (WSF-...

      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)

      by borroff (267566) on Tuesday June 01, 2004 @02:09PM (#9306580) Journal
      At least physicists have the decency to choose names like "gluons" instead of "strong nuclear force gauge bosons". Unless I'm in the field, neither "gluons" nor "variable spreading factor orthogonal frequency code division multiplexing" is going to mean that much to me, but "gluons" is a lot easier to say.

    • And this is how to split the name to understand it:

      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)
    • It uses both frequency division multiplexing and code division multiplexing.

      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)

        by IncohereD (513627)
        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 [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
  • by giliath (200249) on Tuesday June 01, 2004 @01:59PM (#9306429)
    Who comes up with these names, and how does Japan manage to stay lightyears ahead of everyone else in wireless
    Part of the reason they are able to stay ahead of everyone else is the density of the country. It is a lot easier to deploy new technologies like this when they don't have to worry about huge land masses like found in China/USA/Russia, and even somewhat in Europe.
  • Ahem! (Score:5, Funny)

    by orthogonal (588627) on Tuesday June 01, 2004 @01:59PM (#9306431) Journal
    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 [slashdot.org].)
  • by Nerviswreck (238452) on Tuesday June 01, 2004 @01:59PM (#9306432)
    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
    • Japan is not small. 135 million people, many of which with cell phones that would have to be upgraded.

      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
    • There's that...

      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. ;\
  • by VanWEric (700062) on Tuesday June 01, 2004 @02:00PM (#9306439)
    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!
    • You could just -- I don't know -- turn the fucking thing off while driving. My voice mail message actually says "I'm either out of the calling area or driving...leave a message." I'm distracted enough by the iPod, and that's made for one handed operation (and only gets picked up once every hour or so, to skip over the skits on hip-hop records).
  • Bandwidth (Score:3, Funny)

    by aardvarkjoe (156801) on Tuesday June 01, 2004 @02:00PM (#9306453)
    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?
  • by moehoward (668736) on Tuesday June 01, 2004 @02:01PM (#9306458)

    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)

    by Anonymous Coward
    You sure it's not WTF-OFCDM?
  • Small area to cover. And a population that is willing to send more on the latest gadgets than we are. Heck, most people here just take whatever phone comes with the plan.
  • Yes Yes.. (Score:3, Interesting)

    by Rytr23 (704409) on Tuesday June 01, 2004 @02:02PM (#9306486)
    High speed data is fantastic..but will it prevent me from having dropped calls?
    • High speed data is fantastic..but will it prevent me from having dropped calls?

      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.

  • 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.

    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"

  • by nomad63 (686331) on Tuesday June 01, 2004 @02:02PM (#9306490)
    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...
  • by pegr (46683) * on Tuesday June 01, 2004 @02:03PM (#9306492) Homepage Journal
    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...
  • Rehtorical question? (Score:5, Informative)

    by epiphani (254981) <epiphani@nospAM.dal.net> on Tuesday June 01, 2004 @02:03PM (#9306499)
    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 [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.
  • 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.
  • by blanks (108019) on Tuesday June 01, 2004 @02:05PM (#9306519) Homepage Journal
    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.
    • People will only upgrade when their gadgets break, or a new technology comes out they really need.

      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
  • Were they driving the wrong way down a one-way street naked from the waist down and surfing for child porn on a hacked wireless connection? If not they should talk to this [canoe.ca] man.
  • Great. (Score:2, Funny)

    by Snarph (596331)
    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).

  • I'm not kidding. 20 people or so who are willing to mortgage their lives away, license this technology and get it out the door.

    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. ;)
    • I'm CCNA nearing CCNP test readiness, have MANY years of ISP running experience, and am a bit fed up with the unlicensed spectrum.

      Licensed technology. Real throughput. Cheap bandwidth abound to link it to.....ah, a network engineer's dream. And nightmare.
  • It's 'cause Japanese wireless companies tend to work together to advance forward instead of trying to promote their own standards and slowing things down.

    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
  • by raistphrk (203742) on Tuesday June 01, 2004 @02:14PM (#9306664)
    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.
  • Play Unreal Tournament while crash..er driving my car. Headshot! Multi Kill! mmmm Monster Kill! mmmm Monsterrrrrrrrrrrrchchchc boom.

    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.

  • how does Japan manage to stay lightyears ahead of everyone else in wireless?

    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
  • by Omega1045 (584264)
    variable spreading factor orthogonal frequency code division multiplexing

    Is that like multi-modal reflection sorting? (link [216.239.51.104])

  • variable spreading factor orthogonal frequency code division multiplexing

    Wow, that's the coolest name ever...

  • by Assmasher (456699) on Tuesday June 01, 2004 @02:20PM (#9306750) Journal
    It would be nice to mention that before the furor erupts...
  • by Peter Cooper (660482) on Tuesday June 01, 2004 @02:20PM (#9306754) Homepage Journal
    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.
  • by FatPaulie (197122) <paulie@fat[ ]lie.com ['pau' in gap]> on Tuesday June 01, 2004 @02:30PM (#9306855) Homepage
    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.
  • Well (Score:3, Insightful)

    by cubicledrone (681598) on Tuesday June 01, 2004 @02:30PM (#9306861)
    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.
    • The Japanese have that whole "honor" thing going, culture-wide, which I'm sure is a contributing factor. There's also the fact that they approach business the way our generals approach warfare. When was the last time you heard of a general firing several platoons, outsourcing munitions resupply and comminucations to India, running the Division into the ground and bouncing on to the next Division with a severance package the size of a smaller country's GNP?

      Of course, our Generals have to report to the pen
  • how does Japan manage to stay lightyears ahead of everyone else in wireless?

    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 comes up with these names, and how does Japan manage to stay lightyears ahead of everyone else in wireless?

    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.
  • ... that 4G does not exist. What exists is a memorandum of understanding as far as the expected and required performance shall be.
    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...)

  • variable spreading factor orthogonal frequency code division multiplexing (WSF-OFCDM) downstream technology

    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)

    by TheSync (5291) on Tuesday June 01, 2004 @02:48PM (#9307142) Journal
    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 [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)

    by milamber3 (173273)
    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)?
  • Isn't that shared, not switched, bandwidth? What happens to the speed when you aren't the only one in the whole damn country using the pipe?

    Just like 802.11b -- where throughput drops proportionally to the number of active users.

    -Charles
  • WSF is obviously a /. typo. Even on NTT DoCoMo's own website [nttdocomo.co.jp] they refer to it as VSF-OFCDM.

    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!
  • ..never mind the technology, my techno-analfabetic friends will certainly look up to me when I go tell them about the newest gadget I got:
    "A variable spreading factor orthogonal frequency code division multiplexing downstream device."
    "Wow... does that come with an optical mouse ?"

    Can't wait to gloat :)
  • "variable spreading factor orthogonal frequency code division multiplexing (WSF-OFCDM) downstream technology"

    I guess they must spell variable wariable.

  • Are bandwidth prices going to go down enough to make this feasable for the masses. I'm sure that's nice but I dont see DSL, Colocation, and other providers upping the ante on bandwidth anywhere. Most people have even seen their speedy DSL connections hacked time and time again until they're at 256/64 vs the 1.544/768 many started with when DSL became available. Even when I first got a cable modem through RoadRunner back in 2000 in NC during the testing phase and for a short while afterwards it was workin
  • magic numbers? (Score:3, Interesting)

    by Doc Ruby (173196) on Tuesday June 01, 2004 @05:01PM (#9309122) Homepage Journal
    "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.
    • Re:magic numbers? (Score:4, Informative)

      by muonzoo (106581) on Tuesday June 01, 2004 @06:39PM (#9310082) Homepage
      How do they get 3bits per cycle? Nyquist frequency limits mean 100MHz could optimally carry 50Mbps, not 6 times that in an actual test.


      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)

      by jquirke (473496)
      I believe you are confusing the Nyquist Theorem [techtarget.com] with Shannon's Law [mpirical.com].

      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

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