TD-LTE Wave Sweeping Across the Globe

Over the past 20 years, mobile communications have developed rapidly from analog to digital, voice to data, narrowband to broadband, and single mode to multimode with the aim of broader bandwidth and more diverse services. A wide range of smart terminals have emerged, and mobile Internet services are changing from day to day. Explosive growth in data traffic has put much pressure on network operators. Ever-increasing user demand is driving technological advances, and these technological advances stimulate user demand.

The Choice of TD-LTE

Demand for high-speed wireless data and fast service provision is a key driving force for the advancement of wireless technologies. Wireless technologies are also being advanced to leverage existing 2G and 3G resources, cut TCO, and maximize cost benefits. LTE fulfills these needs and is important in the evolution of wireless technologies.

LTE can be classified as TD-LTE or FDD-LTE, and the differences between these two are nearly all in the duplex mode. Compared with FDD, asymmetric TDD is more flexible in its use of spectrum resources and can better meet the requirements of mobile Internet dominated by asymmetric services. TD-LTE is becoming the global technology of choice for unpaired spectrum. With 4G approaching, TD-LTE is the optimal choice for operators that use WiMAX and PHS because it provides high spectral efficiency and allows operators to expand quickly and reap cost advantages that derive from such expansion.

In most scenarios, the ratio of data uploading to downloading is 1:10. TD-LTE provides multiple time slot configurations that allow capacity to be flexibly allocated to the uplink and downlink. TD-LTE also provides a downlink rate of up to 100 Mbps. Therefore, TD-LTE is the best choice for operators seeking to mitigate data traffic pressure.

TD-LTE and LTE FDD share the same core network and most of the standards and design. They allow seamless interoperability between 4G and 2G/3G networks. LTE is the preferred choice for operators that provide voice and low-speed data services over 2G and 3G networks and that want to co-locate TDD and FDD sites in order to share existing infrastructure.

Building a TD-LTE Ecosystem

Mass supply of TD-LTE terminals is a symbol of maturity in the TD-LTE industrial chain. In February 2011, China Mobile, together with Softband, Bharit, Vodafone, Clearwire, and other operators, established the Global TD-LTE Initiative (GTI). GTI aims to work with industrial partners to build a strong and thriving TD-LTE ecosystem, promote the commercial deployment of TD-LTE worldwide, and provide subscribers with mobile Internet terminals that perform optimally and give the best user experience. Currently, 32 members from Asia, Europe, America, and Oceania are jointly researching key commercial issues, such as global roaming terminals, multiantenna techniques, and intra-frequency networking. They are seeking to accelerate the development of the TD-LTE industry through concerted effort.

Smartphones and semiconductor devices have always been a major bottleneck for the development of TD-SCDMA. However, TD-LTE has aroused considerable interest from the world’s leading semiconductor device manufacturers. Altogether, 18 manufacturers worldwide have researched and invested in TD-LTE semiconductors. Qualcomm and ST-Ericsson recently announced the sampling of multimode LTE/3G chips, which is a significant milestone on the way to solving the TD-LTE bottleneck problem. At present, HTC, Media Tek and Quanta from Taiwan, ZTE, Hisilicon, Leadcore and Yulong are the dominant suppliers of TD-LTE terminals. In 2012, Hisilicon will launch five-mode chips that support GSM, CDMA, UMTS, TD-LTE and FDD LTE. ZTE will launch commercial TD-SCDMA and TDD-LTE multimode terminals, which are directed towards uFi (supporting TD-LTE wireless hot spots) and smartphones.

Apple has also promised to launch an iPhone that supports TD-LTE. This was promised by Tim Cook, CEO of Apple, when he visited China Mobile as COO. 

TD-LTE Deployments Worldwide 

In September 2011, China Mobile completed the first phase of its TD-LTE trial in Guangzhou, Shenzhen, Shanghai, Hangzhou, Nanjing, and Xiamen. The test results showed that TD-LTE performance is satisfactory and industry requirements can be met. Both TD-LTE infrastructure and terminals qualify for commercial use.

In November 2011, Japan’s third largest mobile operator, Softbank, made AXGP commercially available. AXGP is similar to TD-LTE, and has been deployed in Japan in conjunction with ZTE and Huawei. Two thousand base stations were built in the first phase, and there will be up to 10,000 base stations built in the second phase. Ninety-nine percent of the Japanese population will be covered by 2012. So far, the Softbank network is the largest commercial TD-LTE network in the world. Wang Jianzhou, chairman of China Mobile, said, “If in the past the TD-LTE network was just a stratagem on paper, now it has turned into a reality.”

In September 2011, Mobily launched its commercial TD-LTE network covering 10 cities in Saudi Arabia. It is expected that the TD-LTE network will be available in 30 cities in Saudi Arabia by 2012, covering 85% of the country’s population.

In India, Reliance, Bharti, Aircel, and Tikona plan to launch their TD-LTE commercial networks in the first half of 2012. These companies are focused on the burgeoning tablet PC to make supplement to their existing services.

Swedish operator, Hi3G, will work with ZTE to commercialize its 4G network, the world’s largest TD-LTE/LTE FDD dual-mode network, by the end of 2011.

Clearwire from the US and Sky TV from Brazil have also decided to join the TD-LTE group. Other regions where TD-LTE has great potential are Southeast Asia, South America, Canada, the Middle East, Africa, and Russia. According to statistics from China Mobile, two operators worldwide have officially launched TD-LTE commercial services, and ten operators have made plans for commercial services. More than 30 TD-LTE trial networks have been constructed in North America, Europe, and Asia. The number of TD-LTE base stations is estimated to reach 6,500 by the end of 2011 and 30,000 by the end of 2012.

Looking to the Future

According to a forecast by Goldman Sachs, global TD-LTE CAPEX could reach US$15 billion to US$20 billion from 2012 to 2014 and attract more than 40 million subscribers. China Mobile’s first phase of TD-LTE network trial includes 850 base stations in six cities in China. Half of China Mobile’s 230,000 TD-SCDMA base stations will be gradually upgraded to TD-LTE. China Mobile will deploy 10,000 to 20,000 TD-LTE base stations across China by 2012.

China Mobile, Bharti, and Softbank will launch more TD-LTE commercial services by the end of 2012 and into 2013. China, India and Japan, where these TD-LTE services will be offered, have a population of 2.7 billion, 39% of the world’s population. The market potential for TD-LTE in these countries is very significant.

TD-LTE Development Milestones

November 2008: Qualcomm announced it was ending development of UMB, favoring LTE instead

March 2009: 3GPP froze the specifications for LTE Release 8

October 2010: TD-LTE-Advanced was chosen by the ITU as a candidate for the 4G wireless communication standard

September 2011: The world’s first commercial TD-LTE network was officially announced.

2012: A TD-LTE tide will sweep across the globe.