China Mobile Ltd. is on the verge of building what could ultimately be the world's largest Internet access network as it starts the construction of an LTE TDD-based 4G radio access network that will comprise macro and small cells.
The operator, which has begun commercial trials of its 4G services, aims to roll out a network -- focused on densely-populated cities -- that is far more competitive than its existing 3G network, which was based on China's home-grown TD-SCDMA system.
To put it into perspective, China Mobile expects to have 200,000 LTE TDD macro base stations in service by the end of 2013 and 390,000 by the end of 2014. That compares with the 350,000 base stations it has for 3G, and the 600,000 2G GSM sites that today carry the bulk of its mobile traffic.
A mere 15 percent of China Mobile's 730 million mobile customers are on its undersized 3G network and the operator is determined its 4G network will do better. To achieve its rollout targets will require considerable investment, which is why the carrier has allocated billions of dollars from its 2013 capex budget towards the 4G rollout. (See China Mobile's Capex Blowout.)
The operator is working with a number of vendor partners to plan its next-generation mobile network, including Alcatel-Lucent, which has teamed up with China Mobile to develop technology for LTE TDD metro small cells.
Most 4G deployments globally will utilize the FDD flavor of LTE and that's where the majority of vendor R&D has been focused. But while there are "slight differences" between the two strands of LTE, says Michael Schabel, vice president of small cells at Alcatel-Lucent, the fundamental technologies are the same.
"We have modularized our [radio access] solution. We can basically build up the technology as needed. The form factor is similar; the mounting is similar; the backhaul is similar. We have tried to keep as much of the design as possible," he told Light Reading.
"Looking ahead, we see TD-LTE emerging as a more pressing requirement. We've had support for that for some time, and have integrated our software with several chipset vendors. We're seeing demand not only from China, but also from Softbank in Japan and Sprint in the US. The industry has speculated that once Softbank's investment in Sprint USA takes effect there is an opportunity for greater economies of scale through combination of buying power which could make them very influential operators in the TD-LTE market..
TD-LTE is somewhat different from the 3G TDD mode (TD-SCDMA), sharing a common software stack except for the low level Layer 1 and parts of Layer 2. From a deployment perspective, there is at least 80% re-use of our LTE software – we simply turn on the TDD variant within our existing stack. By contrast, 3G TD-SCDMA requires significantly more dedicated software.
China Mobile also continues to want to evolve TD-SCDMA which now has over 100 million active users.
*****Today, Mindspeed is the only silicon vendor with support for both 3G TD-SCDMA and TD-LTE on the same chip and demonstrated this at MWC."***** (emphasis mine)
From "Radisys report lessons learnt from recent LTE small cell network deployments," published on Tuesday, 16 April 2013, written by David Chambers, ThinkSmallCell
"China Mobile said its 2012 profit grew 2.7 percent to $20.8 billion, almost half the growth rate of the 5.2 percent the operator saw in 2011. However, its 2012 revenue rose 6.1 percent to $72 billion. China Mobile is the world's largest mobile operator with 710 million subscribers."