There's hope for unified networks after all

During the event, Qualcomm Inc. and HiSilicon Technologies Co. Ltd announced multimode chipsets that support both the FDD and TD flavors of the LTE. Separately, China Mobile Ltd pledged to launch a converged TD/FDD LTE network this year in Hong Kong and Vodafone Ltd 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 a 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 networks, a technology seen as largely a failure on the global stage, and the follow on TD-LTE for 4G.

- Rick Merritt
??EE Times

Yue has pledged to to have 20,000 TD-LTE-capable base stations.

Even today, China Mobile is still pursuing a split road map of TD-LTE and converged TD/FDD networks.

In a speech at the MWC, 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 promoting the converged network.