When it comes to LTE TDD, June has been a big month

Daryl Schoolar ovum

Daryl Schoolar

I think it is fair to say, as a whole, that the month of June has been a big step forward for LTE TDD. Several events have transpired this month important to the technology's development and global acceptance.

The fist announcement that caught my eyes was ZTE's announcement of a successful voice over LTE TDD call on a network that it is supplying to China Mobile (base stations and IMS core) and using devices powered by Marvell's chipsets.  I see this as signification in two ways. First it was done on a currently deployed network, showing that LTE TDD can support voice services. Secondly, while most mobile operators aren't using voice over LTE in any form yet and it could be many years before VoLTE has widespread adoption, support of voice over LTE TDD support is an important aspect in LTE TDD's continued progress to reach service parity with the FDD version of LTE. Operators wanting to deploy a dual mode LTE network (FDD and TDD) will be able to support a similar voice service no matter the coverage. 

Nokia Siemens Networks got into the LTE TDD announcement game as well in June with its claim of setting an upload record of 56 Mbps using a 20MHz channel. This is not the first time NSN has claimed an upload performance record for LTE TDD, having announced two such records during 2012. NSN also made sure in its recent announcement to note that this recent achievement is just part of the vendor's 15-year commitment to time division (TD) technologies. One of the concerns I get from mobile operators when it comes to LTE TDD is that network supply options are limited to just Chinese vendors.  With 15-years of support for TD technologies, that is clearly not the case with NSN. Furthermore, continuing to set new performance records shows this is an important area for the vendor as a source of R&D investment.  NSN when it comes to western network vendors isn't alone as both Ericsson and Alcatel-Lucent are actively pursuing LTE TDD opportunities as well.  Both of those vendors, along with NSN, Huawei, and ZTE are participating in China Mobile's LTE TDD trial.

Of course ZTE and NSN's announcements mean nothing without mobile operator support for LTE TDD, and in that regard June brought two very significant step forwards for the technology.

Here at the end of June it appears that SoftBank, Sprint, and Clearwire have cleared investor objections and unwanted attention from Dish Network, and will be able to proceed with their plans to form a single entity. This is good news for LTE TDD proponents and this three-way service provider tie up will eventually lead to multi-mode LTE networks in both Japan and the US.  LTE TDD should benefit from being deployed in two high-profile networks in developed economies that have high smartphone penetration rates. Device vendors will be more likely to support multi-mode LTE smartphones thanks to the volumes that can be driven by SoftBank and Sprint in their respective markets. Those volumes should help drive down device prices and make those devices more affordable in markets with less developed economies. Also these two mobile operators, if successful with their multi-mode LTE network build, should encourage other mobile operators to do the same thus increasing the market for LTE TDD gear. Unpaired spectrum used by LTE TDD has been historically an underutilized asset. LTE TDD can change that, and open up more spectrum for mobile operators to use. Certainly with all the cries of spectrum shortage this is a good thing.

The biggest thing by far to happen to LTE TDD in June was that China Mobile finally announced plans for the next phase of its LTE TDD network trial. China Mobile will open up bidding for 207,000 LTE TDD base stations starting July 15th. There had been previous speculation that China Mobile would possibly delay this step in its network build until the end of 2013. By keeping on its original mid-year schedule China Mobile ensures LTE TDD won't lose any of its market momentum. With China Mobile being one of the original supporters for LTE TDD it is important that it remain firm in its commitment to the technology. Plus the size of this trial at over 200,000 base stations will ensure network vendors remain on board with the technology as well.  The size of this trial dwarfs some fully commercial networks. Everybody who follows LTE TDD had been waiting to see what China Mobile would do next, and this tender for 207,000 base stations is exactly what those watchers had been hoping for as it ensures a solid foundation for the technology.

As it stands today LTE TDD trails LTE FDD in terms of market development.  In just number of commercial networks LTE FDD networks are in the hundreds while LTE TDD still remains in the teens. Subscribers and device availability for LTE TDD also significantly trails that of LTE FDD as well. However, the LTE TDD ecosystem continues to accelerate and June has been a big month when it comes to that acceleration. Sure, I expect there will still be people who see LTE TDD as a China only technology and question its global appeal, but a few more months like June should put that to rest.

Daryl Schoolar is Principal Analyst of Wireless Infrastructure for Ovum. Daryl's research includes not only what infrastructure vendors are developing in those areas, but how mobile operators are deploying and using those wireless networking solutions. Contact him at [email protected] and follow him at @DHSchoolar.