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 37 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 DEC 2012 38 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 39 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 DEC 2012 40