Wednesday, May 14, 2014

NTT Docomo Voice over LTE (VoLTE) service will start in June

NTT Docomo announced today that VoLTE is planned to start in late June. Currently, even for LTE phones, voice is transmitted over the old W-CDMA (3G) network. I'm most interested in how VoLTE from NTT Docomo will affect voice pricing for MVNOs. I believe there is expectations that this will lower wholesale costs.

With VoLTE, audio quality should be improved, due to higher bandwidth (50Hz – 7kHz), which should allow for the use of a better codec. Compared to existing LTE phones, calls should connect faster (since there is no switching to 3G). VoLTE phones can also receive area mail alerts (like the earthquake warnings) while a call is connected. With all the free chat options now available, I doubt it matters any more, but the video calling with also have improved quality over the existing FOMA terebi denwa.

The price plan will include the "kake-houdai" Unlimited Calling announced recently, which is ¥2,700. At launch, four phones will be supported (through software updates). These are:

  • GALAXY S5 SC-04F
  • Xperiz Z2 SO-03F

Sometime after July, updates will come to two tablets (AQUOS PAD SH-06F and the Xperia Z2 Tablet) that will enable VoLTE.

Now that the summer line up has been announced, I would recommend that you don't immediately look for a way to flash a custom OS onto your new phone, as you won't be able to receive the update to enable VoLTE.


  1. Hi! your blog is really helpful and information is just perfect!!

    I am got an ONEPLUS phone ( and I am currently using iphone from AU,

    do you know if it is possible to use au LTE on oneplus phone since it seems

    it is supported in above frequency bands?

    If it doesn't work, would you suggest I change to Docomo, softbank or Y-mobile for future uses??

  2. Hello everyone. I woudl like to ask for some advice; I will spend the full year 2015 in Japan and I'd like to bring my LG G2 (D802 model) along with me. I'm trying to solve the operator situation. For what I've read the best option would me an MVNO.

    Could anyone recommend me an operator/plan? My priority is DATA, full LTE speed if possible.

    There are my phones frq specs :D
    Thanks a lot!2G NetworkGSM 850 / 900 / 1800 / 1900
    3G NetworkHSDPA 850 / 900 / 1900 / 2100
    4G NetworkLTE 800 / 900 / 1800 / 2100 / 2600

  3. On a related topic, can anyone tell me if there is a difference in speed between Mopera and Sp Mode APNs with Docomo. I'm confused about the differences between these two Docomo APNs and especially if there's a difference with their data speeds. Thanks for any insight into this.

  4. Hi all. I'm curious if there are any in Japan here with experience bringing in a Galaxy Note 4 N910U (HK) or N910F (Europe) and whether Docomo FDD LTE Band 1 (2100) access was successful. Both versions support the band on paper.

    BTW I recently switched from Docomo Xi contract to an OCN Sim on my unlocked Docomo Note 2 and am liking it @ 1/5 the monthly fee. Kept my 090#, plus gained a 050# with much lower per minute rates.

  5. Hi Serlex,
    Did you have any success with your G2 and LTE? If so which band/frequency/provider?


  6. I'm using the Bic SIM solg and BIC CAMERA. Service is provided by IJJ MIO.

    IT Works fantastic.