Friday, February 10, 2012

Japanese carrier plans for LTE

A good article from Appllio outlining the different plans for next generation "4G" mobile networks. Here is a brief summary in English of the main points of the article.

TD-LTE, which will be used by Softbank, was originally designed only for data and will therefore be able to dynamically allocate bandwidth as needed between uplink and downlink channels. This means that if downloads are congested, needed bandwidth can be taken from the uplink channel. This provides an advantage for data over FDD-LTE that is used by the other carriers and was originally designed for both data and voice.

WiMAX, available from UQ WiMAX (under KDDI), presents four main differences from LTE (from a consumer's point of view).
  1. LTE data plans replace 3G plans, but Wimax is an option added to an existing 3G plan currently for and additional ¥525.
  2. WiMAX currently has no usage limits.
  3. WiMAX has a 2 year head start on Docomo Xi and has a corresponly much larger coverage area of 100 million people.
  4. WiMAX uses a higher frequency than competing LTE networks and is therefore more easily attenuated indoors/underground.
Docomo Has Xi LTE currently available (I use it - but with a 3G handset) and will have 25% of the population covered by April. A year later they expect to have a total of 60%, including all major cities. By 2014, coverage is expected to be at 80% and 98% by 2015. Xi will move up to 100 Mbps around mid year.

KDDI (AU) is currently offering WiMAX. They will roll out LTE from 12/2012, starting with 60% coverage of the population at 75 Mbps. By the beginning of fiscal 2015, they plan to have 96.5% coverage.

Softbank 4G is currently available with an advertised maximum downlink of 110 Mbps (this is apparently not being attained, but 60 Mbps is still good). By the start of fiscal 2013, they expect to cover 99% of the population. Only routers are currently available.

SBM has also announced a FDD-LTE network by mid 2012, but it is unclear if this schedule will be met because of the unfair allocation of channels by the government. AU and Docomo enjoy two channel bands, while SBM is limited to one. This means that SBM has to totally bring down it's LTE network to build out new technology.

The MIC is auctioning off a new allocation of 900 MHz spectrum to only one carrier. If SBM gets it, they're golden. If not, their kinda screwed. [UPDATE: Interestingly, SBM rolled it out for 3G.]

E Access (Emobile) is starting LTE service from the start of fiscal 2012. After one year, they expect to cover 70% of the population. Urban downlink will be at 37.5 Mbps. In rural areas downlink will be 75 Mbps. If they win the 900 MHz allocation, it would likely have an effect on their LTE plans.


  1. I searched around and could not find an answer to this question, but will the Galaxy Nexus work with docomo's Xi? The idea of a totally unlocked phone with updates not filtering through the carriers really appeals to me.

    Docomo's version of the Galaxy Nexus, the SC-04D, appears to be an earlier version that does not include the LTE radio that the straight Galaxy Nexus does include. But maybe the LTE radio included in the Galaxy Nexus won't work with docomo's Xi.

    This would seem to be a good combination -- buying an international version of the Galaxy Nexus and bringing it in and getting docomo's red SIM with the 7GB monthly Xi account. Is anyone doing this?

    Even if the LTE frequencies are different, it still seems feasible to get the Red SIM and just use 3G on this phone. Or would bmobile or eMobile have a better plan medium data, very light voice, and lots of tethering for the Galaxy Nexus?

  2. Thanks, SBSdroid. I had seen the page you linked to. But it is still not clear to me. Earlier SBS had said "NTT Docomo is using 1500 MHz for their "Xi" LTE" (I've also seen 2100 MHz, but ...) The Galaxy Nexus appears to be coming out with different versions specifically for different LTE networks. So, if Samsung produces a 1500 MHz LTE version for any market, we would be able to use the phone here on docomo's Xi network, right?

    I'm having a hard time finding listings for which version of the LTE frequency the various sellers of the Galaxy Nexus are offering.

  3. yeah, if it supports Docomo's frequencies, but ASFAIK, the LTE radios aren't being designed like that. As as you're finding information is scare on LTE radios.

    2100 MHz is wrong by the way for Xi. It's 1500. I think they'll phase in 2100 as they phase out FOMA. No idea what they plan for the 800 MHz.

  4. I was looking at some stuff about the SO-04D (hayabusa) and SC-05D (Galaxy Note LTE) and that information seems to claim that they will run on LTE 2100.
    Strangely, some information on the F-01D (Arrows Tab LTE) and SC-01D (Galaxy Tab 10.1 LTE) also seem to claim to be LTE 2100.

    Why do they have to make LTE bands so confusing >_< I can't my device rumours straight.

  5. I just heard that emobile offers totally free calls up to 10 minutes, 300 calls /mo to all carriers and landlines. My question is are emobile handsets unlockable and can they be used in other countries by swapping out the sim card? I'm ready to quit AU as their phones are useless abroad except with expensive roaming service.