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NTT DoCoMo's 4G Tests Hit 300Mbps

Posted by CmdrTaco on 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?"

5 of 259 comments (clear)

  1. Names by bsd4me · · Score: 4, 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.

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    (S(SKK)(SKK))(S(SKK)(SKK))

  2. Population density helps by giliath · · Score: 5, Informative
    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.
  3. Rehtorical question? by epiphani · · Score: 4, Informative

    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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  4. Re:their secret is... by mrm677 · · Score: 5, Informative

    ...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.

  5. Re:their secret is... by brianjcain · · Score: 4, Informative

    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.