BARCELONA – The mobile industry took a few small but significant steps toward the holy grail of a unified technology at the Mobile World Congress here.
Qualcomm and HiSilicon announced multi-mode chipsets that support both the FDD and TD flavors of the LTE. Separately, China Mobile pledged to launch a converged TD/FDD LTE network this year in Hong Kong and Vodaphone expressed support for the technology.
To date, global carriers have used two or three flavors of cellular technology. The move to a converged TD/FDD LTE network represents the current best hope for ma single global standard.
Currently AT&T and Verizon have led global deployments of LTE, using FDD technology, in part because it was ready first. But operators say the converged approach more efficiently uses scarce operator spectrum and eases global roaming issues.
China Mobile, which has 650 million subscribers, is leading the charge toward unification. Ironically, it also helped fragment current standards by insisting on its own approach of TD-SCDMA for 3G nets, a technology seen as largely a failure on the global stage, and the follow on TD-LTE for 4G.
Even today, China Mobile is still pursuing a split road map of TD-LTE and converged TD/FDD networks.
In a speech at the Mobile World Congress here, Li Yue, chief executive of China Mobile, pledged to have 20,000 base stations capable of running the TD-LTE by the end of the year with commercial operations starting next year in as many as three cities. It currently operates pilots in six cities with about 1,000 TD-LTE base stations.
So far, 3 Scandinavia is the only operator to deploy a FDD/TD network. The operator which serves two million subscribers staged a soft launch of its technology in Stockholm in December.
Operators in India and the Middle east have also pledged support for TD/FDD nets. So far, AT&T and Version have only said they are studying the technology.
Jorgen Askeroth, chief technology officer of 3 Scandinavia, said the technology is performing better than expected and is more efficient in its use of spectrum than separate TD and FDD nets. In addition, he said, several chip makers including ST-Ericsson are planning multiband chips.
Qualcomm showed a 28nm multiband chip set. HiSilicon, the chip division of Huawei, showed a 40 nm chip. Examples of both chips were encased in glass diamonds at an event here promoting the move to a converged net.
“To hear the commitment China Mobile is making to the advancement of TD/FDD is significant,” said Craig Ehrlich, chairman of GTI, a trade group pr\omoting the converged network and host of an event on the technology here.
There is considerable argument for and against TD-LTE Vs FDD-LTE. An excellent summary is available at: http://www.ascom.com/en/tems-fdd-lte-vs-td-lte-12.pdf
The salient points are:
TD-LTE is better suited for M2M where continuous up link and down link operations (simultaneously) are not needed.
Total spectrum in TDD - 1133 MHz (in 11 bands)
Total spectrum in FDD - 1658 MHz (in 25 bands)
Other considerations for TDD would be in terms of hand off under full mobility conditions.
It is not that Verizon and AT&T have deployed FDD LTE simply because of availability. It actually can show improvement over typical 3G service that are operated by them. If they chose the TD version (even later) for regular customers, it may actually look like a reversal since TD-LTE will not be able to match the data rates offered by FDD versions.
I would like to believe Qualcomm being a intellectual property base rather than a manufacturer; it will keep tabs on its designs that are by no means easy to tap.
Having said that, the vague temptation of doing chips in China continues to attract many.
I hope that Qualcomm does not repeat the same mistake as Motorola in the early '90s when it started giving away technology to China in the hope that in turn the Chinese Govt. would give Moto exclusive rights to Base Station infrastructure.
The Chinese played Motorola for a chump. The MOS Fab that Motorola had put up a in Tianjin was basically looted for technology.
We all know how Motorola, once leader in Cell phones, fell apart.
The scion of the Jacobs family ( QC ) is perhaps smarter than that of the Galvin family ( Moto ).
From a technical point of view this has always made sense. Qualcomm was the rebel outlier when CDMA was the challenger to GSM, but now that those two have converged China Mobile is the new troublemaker. In order to bring them in line the Chinese government has to be satisfied that converged TDD/FTE LTE meets their needs. The big question is whether or not they can control that network and monitor the traffic. All other issues are at best secondary.
Interesting story Rick, looks like China (with Qualcomm's help) will drive NG wireless standards...I think FDD/TD combo makes sense as spectrum is scare and you need all possible tricks to fill all wireless channels to full capacity...I presume FDD stands for Frequency Division Duplex and TD for Time Division Duplex. I wonder though why they dropped second D in TDD to make it TD while kept it in FDD (rather than make it FD)...Kris
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