LTE – The First Global Cellular Standard – But Does it Matter?

Indeed on first thought, LTE will be the first global cellular standard in the future to which GSM, UMTS/HSPA, CDMA and potentially other cellular wireless technologies are likely to converge on. But does it really change anything?

Being a global standard does not necessarily mean all LTE capable devices can communicate with all networks around the globe. There are two main issues:

1) FDD and TDD Mode

While in most parts of the world, FDD (Frequency Division Duplex) will be the dominant air interface technology, TDD (Time Division Duplex) is pushed especially by China as an upgrade path for TD-SCDMA. So an FDD LTE device will not be able to use a TDD network and vice versa. With some luck, we might see devices that can do both FDD and TDD but nobody's really commenting on how feasible this really is. Only time will tell.

2) Two Dozen Different Frequency Bands

What's worse is the number of frequency bands are foreseen for LTE. In practice, this will mean that devices will be built for some but not all of those frequency bands. So it's nice to have a global standard but it's unlikely the mobile devices themselves will be usable on a global scale. The single 4G device working everywhere will remain a nice dream.

A Little Light At The End Of The Tunnel For Vendors

LTE being a global standard is a good thing for network equipment vendors. Most of the equipment will be the same including the base stations where only a few parts or modules are different to work on a different frequency band or operating mode (TDD/FDD).

Benefits For Network Operators

An economy of scale is created for networks operating on the
main LTE frequency bands (e.g. 900, 1800, 2100 and 2600 MHz). Most other frequency bands are only used by a few network operators so it's unlikely these will get the same prices from network vendors as their colleagues who use the mainstream bands. Also, the number of devices working outside the standard LTE bands are likely to be as limited as for UMTS/HSPA today. Just have a look of how many 3G devices are available for HSPA network in the U.S. compared to Europe.

Benefits For Users

For the users, I don't see a big change from the situation with HSPA today. Where the mainstream frequencies are used, there is a big choice of devices and this is likely to be the same with LTE. And network operators using less used frequency ranges will probably receive as few devices as those operating 3G network in such bands today.

What We Really Need

So what we really need is not only a global standard but also global frequency bands so everyone benefits the same. But, unfortunately, that's a dream that is very unlikely to come true anytime soon.

5 thoughts on “LTE – The First Global Cellular Standard – But Does it Matter?”

  1. Global frequency bands is as elusive as a global Government. In its absence, having a global cellular system either defacto or dejure is the next best thing :). An idea could be just as we have in the base station a baseband part and radio part, why not have a common baseband part in the devices with interchangeable radio part for specific frequencies. :). It could solve lot of issues with regard to roaming etc.

  2. The TDD/FDD story is interesting but several of the large chipset vendors have committed dual-mode FDD and TDD chipsets, see the announcements at MWC and the adjacent event for TDD-LTE held by CMCC, Vodafone and VzW.

    The momentum behind TDD is increasing and could be an interesting evolution as current TDD spectrum in for example Europe might not be commercially viable to use for WiMAX but a TDD-LTE Data only network might be commercially viable given the economy of scale of LTE compared to WiMAX.

  3. I do agree with Martin’s point. Maybe after some time, DD band might become the global LTE band (however is quite different for Region 1 and Region 2 and Asia, so this makes things more complicated)

    I see it this way: Most LTE commitments so far will be deployed in the 2.6 and digital dividend band. GSM/UMTS bands will be used gradually when migrating users to LTE, so i think that at the beginning a couple of bands should be supported. After the market is more mature and clear, common G/U/L band combinations will arise for mobile devices.

    I have faith that, as LTE market matures, advances in technologies like SDR, Cognitive Radio and configurable RF for mobile devices will help enabling roaming and global services.

  4. Hi Petrut,

    Ajit Jaokar and I will do one at the University of Oxford in December. If you can wait that long, it might be worth considering… 🙂

    Kind regards,

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