Perspectives
LTE TDD terminals come of age
On October 8, 2012, SoftBank, currently the world’s largest LTE TDD operator,
released six compatible smartphones for its 4G network, the first and largest release thus
far for this technology, giving it a shot in the arm on the global scene.
By Xu Nan
A
ccording to LTE TDD Goes Mainstream (an
Ovum report), LTE TDD has gained wide
ecosystem acceptance and backing from
leading infrastructure and device vendors,
with 45 network commitments made worldwide to this
technology, which has converged with others for mobile,
both in terms of infrastructure and at the user end.
LTE TDD chipset development
T h e f i r s t LT E T D D d e v i c e c h i p s e t d e b u t e d
commercially in 2009, representing the first of three
developmental stages for this technology.
Commercial debut (2009-2011)
Selection in the early days was limited to the
MDM9x00 from Qualcomm and the Balong700 from
Hisilicon. And while these early efforts supported features
specific to LTE TDD such as beamforming, they never
moved beyond the dongle.
In October 2011, SoftBank launched its LTE TDD
network on the 2.6GHz band (Band 41), offering just
two end-user devices at the time, both mobile Wi-Fi, from
Seiko and Huawei. Also in 2011, China Mobile launched
an LTE TDD pilot network in Hangzhou (a Chinese
provincial capital), providing free LTE TDD access services
through Wi-Fi on bus lines and Wi-Fi CPE leasing services
for individual customers with monthly packages.
Both operators opted for Wi-Fi access to whet
consumer appetites for LTE beyond the usual circle of
early adopters, while helping to alleviate the traffic burdens
on their older infrastructure.
Commercial acceptance (2012-2013)
Huawei Ascend P1 LTE
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This stage has seen the arrival of multi-mode, multiband chipsets and smartphones. Qualcomm and Hisilicon
still respectively represent the two pillars of the LTE TDD
industry through their MSM8960 and Balong710 (an
upgraded version of the Balong700) chipsets, but this time
all the mainstream vendors have joined the game; in other
words, LTE TDD has achieved widespread acceptance.
The 2012 Mobile World Congress saw the release
DEC 2012
As far as end users are concerned – the simpler, the better. Terminal
chipsets must be highly integrated, with faster speeds, less power consumption,
smaller sizes, lower failure rates, and reduced costs, if LTE TDD is to become
a true mainstream technology with consumers.
of the Balong710, the world’s first chipset to support
LTE Category 4, with Qualcomm and Altair serving
up competing offerings shortly after. In July 2012, Intel
announced the launch of a joint lab with Hisilicon for
LTE TDD chipset development, marking a major venture
into the mobile arena for the Santa Clara giant. September
2012 saw the certification of Sequans’ second-generation
LTE TDD chipset (Andromeda), by China’s Ministry of
Industry and Information Technology, while Qualcomm
released its second LTE TDD chipset for smartphones, the
MSM8930, a cousin of the MSM8960. In October 2012,
Marvell, one of the biggest suppliers of TD-SCDMA
smartphone chipsets, announced the PXA1802 chipset
for LTE, while Broadcom, STE, and Samsung have all
announced plans to release comparable offerings in late
2012 or early 2013.
One thing of note is that most of these chipsets are
both multi-mode and multi-band, supporting LTE TDD
and LTE FDD/UMTS/TD-SCDMA/GSM, which will
no doubt drive uptake for LTE TDD-compatible devices,
thanks to this broader compatibility and the fact that very
little if anything will have to be given up when users in
LTE TDD-serviced areas make the leap to this technology,
both in terms of capability and selection – a big plus.
In addition, most second-gen LTE TDD chips in use
are designed to support smartphone interworking through
features such as CSFB, Flash CSFB, and PS Handover,
while their energy efficiency and high level of integration
make them better suited for handset use.
Over 110 LTE TDD terminals have been released thus
far, and this number is expected to exceed 200 by mid2013, when the market reaches maturity.
Ubiquity (2013+)
As far as end users are concerned – the simpler, the
better. Terminal chipsets must be highly integrated, with
faster speeds, less power consumption, smaller sizes, lower
failure rates, and reduced costs, if LTE TDD is to become
a true mainstream technology with consumers.
Global roaming should be possible in two to three
years as the 1.9/2.0/3.5GHz spectra open up and join
2.3/2.6GHz as the primary LTE TDD bands. Another
technology that will drive LTE TDD beyond its regional
origins is LTE-Advanced, as key features such as carrier
aggregation, HetNet, and high-end MIMO enable
operators to better utilize their fragmented spectrum
holdings.
Current LTE terminal offerings from the likes of
Verizon, AT&T, SoftBank, Mobily, and Bharti Airtel are
all at the high end, but this should change soon enough
as chipsets develop faster than Moore’s Law. As multimode LTE chipsets increasingly share an ecosystem where
this technology accounts for an ever larger percentage of
coverage, the costs of LTE devices will ultimately reach
UMTS levels, enabling access to the former at every price
point.
Chipsets are more than ready
The absence of LTE TDD smartphones, thus far,
has been an industry concern, but things are starting to
change thanks to the efforts of operators such as SoftBank,
which launched six TDD smartphones in Q3 2012. But
fortunately for this technology, it should avoid some of the
growing pains experienced by FDD (its uptake should be
smoother).
Previously, there had been no dedicated LTE chipsets
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Perspectives
As multi-mode LTE chipsets increasingly share an
ecosystem where this technology accounts for an ever larger percentage
of coverage, the costs of LTE devices will ultimately reach UMTS levels,
enabling access to the former at every price point.
(either FDD or TDD) for smartphones; in other words,
data card chips (such as the MDM9200) were shoehorned
into all early LTE handsets, an unsustainable solution
thanks to their size, power consumption, and general lack
of suitability to the more rough & tumble world of the
mobile terminal.
LTE TDD arrived on the commercial scene later
than its FDD cousin, so the technology never had to go
through this grafted stage. The MSM8960, for instance, is
a smartphone-oriented LTE TDD chipset, based on 28nm
technology, that supports LTE TDD, LTE FDD, UMTS,
CDMA, TD-SCDMA, and GSM.
SoftBank’s six LTE TDD smartphones all use the
MSM8960 or APQ8064 chipsets, while LTE FDD
smartphones (including the Nokia Lumia 920 and
Motorola ATRIX™ HD customized for Verizon and
AT&T, respectively) also utilize the former.
The Motorola RAZR M, on the other hand, adopts
both the MSM8960 chipset and a universal platform that
supports LTE FDD/CDMA for Verizon and LTE TDD/
UMTS for SoftBank.
GSA statistics indicate that the industr y’s first
eleven LTE TDD smartphones use chipsets from either
Qualcomm, MediaTek, and Innofidei, with the former
two leading the market in terms of shipments, serving
brand-name vendors such as Samsung, Sony, HTC, and
LG, who only need to make minor modifications to their
products to support LTE TDD.
Both Qualcomm’s QRD and MediaTek’s turnkey
programs have lowered the threshold for LTE smartphone
design and manufacturing, thanks to the comprehensive
set of solutions they encompass. Combined, these two
vendors dominate the market, which should drive chipset
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design towards a more universal nature that opens the
ecosystem, lowers costs, and simplifies production of the
relevant smartphones.
Continuous efforts from operators
Huawei communicates with major smartphone vendors
regularly and holds a similar view of the industry roadmap.
As the chipsets are ready, adoption now lies primarily with
operator sentiments, and some have been very receptive
to LTE TDD. In August 2012, China Mobile procured
nearly 35,000 LTE TDD devices. In late September, its
CEO indicated that this inventory would be exhausted by
Q1 2013, prompting a further procurement of 200,000
devices by the end of 2012.
Similarly, in October 2012, SoftBank announced plans
to have all future smartphones, besides the six LTE TDD
handsets already in use, be LTE TDD compatible. The
same month also saw launches of Huawei’s Ascend P1
LTE TDD smartphone by STC (Saudi Arabia) and Bharti
Airtel (India).
However, despite all these efforts, LTE TDD’s
momentum is not self-sustaining, though the acquisition
of Sprint by SoftBank (and the former’s more recent bid for
Clearwire) will certainly help to legitimize the technology
in circles where it has been an outsider thus far. Operators
must keep up their promotional efforts, while chipset and
device vendors also need to strengthen the LTE TDD
ecosystem and support operators in this push, so that this
technology is firmly in place in the mainstream.
Editor: Pearl Zhu zhuwenli@huawei.com
DEC 2012
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