Editor’s Note: Welcome to our weekly Reality Check column. We’ve gathered a group of visionaries and veterans in the mobile industry to give their insights into the marketplace.
As 2010 and the first launches of Long-Term Evolution (LTE) networks approach, the global mobile industry is understandably buzzing with speculation about the potential impact of the first entirely new radio technology to be deployed in a decade. With LTE set to become a short-term reality, rather than a long-term vision, it is easy to overlook the extraordinary impact of another young technology – HSPA. Now a standard feature in smartphones, netbooks and many laptops, HSPA is spreading mobile broadband services across the world and, in tandem with HSPA+, could ultimately emulate the longevity and widespread usage of GSM.
For both GSM and CDMA mobile operators, all roads will eventually lead to LTE, but many will travel there via HSPA and HSPA+. The dilemma in the current economic climate is whether to move rapidly to LTE or focus near-term capital spending on HSPA and HSPA+. The answer is a complex one which depends on the mobile operator’s access to spectrum, how congested its network is, the age of its existing base stations and other factors.
LTE stats
Let’s first take a closer look at LTE and what it is capable of. Designed to be compatible with GSM and HSPA, LTE incorporates multiple antennas in combination with an OFDMA air interface in the downlink and Single Carrier FDMA in the uplink to provide high levels of spectral efficiency and peak end user data rates exceeding 100 megabits per second. LTE is flexible enough to be used with a very broad range of spectrum, supporting channel bandwidths of just 1.25 megahertz up to 20 megahertz in both Frequency Division Duplexing (FDD) and Time Division Duplexing (TDD) operation. However, the very high throughput speeds envisioned in LTE’s spec depend on the usage of wide spectrum channels of at least 10 megahertz.
Significantly, LTE has the potential to become the first radio access technology that is used by all the world’s major mobile operators, meaning it could eventually gain massive economies of scale, while also giving users the ability to roam as they do with GSM and HSPA today.
Moreover, LTE isn’t a technology looking for a market. Many mobile operators are going to need the most advanced mobile broadband technologies they can get their hands on to satisfy user demand for accessing videos, social networks, music, email and other multimedia services on the move. The very rapid uptake of HSPA is a clear signal that the industry will need to be on its toes to keep up with the burgeoning appetite for mobile broadband.
HSPA up to the task
Between September 2008 and September 2009, the number of HSPA connections worldwide doubled to more than 150 million and we expect the 200 million milestone to be reached during the first quarter of 2010. And mobile data traffic levels are growing much, much faster. Nokia Siemens Networks estimates that mobile data traffic grew fourfold in 2008 and will rise 300-fold in the next five years. Deutsche Telekom CEO Rene Obermann has also said that mobile data traffic is up several hundred percent year-on-year and that he expects that trend to continue.
Much of this traffic is being generated by HSPA-enabled netbooks, laptops and smartphones with large touchscreens and Web browsers. Vodafone said recently that smartphone owners on average use mobile data services seven times as much as those with WAP-enabled handsets, while the best smartphones generated 24 times as much usage. It is not surprising then that many HSPA operators are moving to upgrade their networks from a typical peak downlink rate today of 3.6 Mbps through to 14.4 Mbps, giving them more capacity to cope with soaring traffic levels.
HSPA progression
From there, an operator’s next step could be to move to HSPA+, which, like LTE, uses multiple antennas and higher order modulation enhancements to enable greater throughput speeds. The first HSPA+ networks, capable of peak downlink speeds of 21 Mbps, went into commercial use in early 2009 in Australia, Hong Kong, Singapore and Austria. By the end of 2009, Telstra in Australia is aiming to raise the peak speed of its HSPA+ network to 42 Mbps. Compared to the first iterations of HSPA, HSPA+ can double the data and voice capacity available to the operator.
The cost of upgrading an HSPA network to HSPA+ depends largely on whether the operator needs to add both new software and hardware to its existing base stations. If the operator’s current base stations were deployed fairly recently, they may be able to move to HSPA+ with just a software upgrade, albeit a major one. For this reason alone, operators with a relatively new HSPA network are likely to upgrade it to HSPA+ to ensure they maximize their return on their initial investment. Of course, some operators may mix and match, deploying only the elements of HSPA+ that can be achieved via a software upgrade, while excluding those elements that require new hardware.
Another very important consideration is the availability of spectrum. Although LTE is versatile enough to be deployed in a wide range of spectrum bands, equipment manufacturers are likely to initially produce devices that are compatible with the 2.6 GHz and 700 MHz spectrum bands, in which several operators have already committed to early LTE deployments. If an operator doesn’t have access to either of these bands, they may decide to hold back from rolling out LTE.
Indeed, the continued success of GSM and HSPA has been driven by coordinated spectrum planning across markets worldwide. This kind of harmonization drives down costs in the chip market and, for LTE to be successful globally, similar spectrum co-ordination needs to take place.
Spectrum availability is probably the biggest challenge facing LTE. But as more governments come to recognize the major social and economic benefits of widespread access to mobile broadband, that situation is likely to change. I’ll stick my neck out and predict that most mobile operators worldwide will have deployed LTE within the next ten years. In many cases, these networks are likely to be supplemented by HSPA+ networks, working together to provide near ubiquitous mobile broadband coverage.
Dan Warren joined the GSM Association (GSMA) in 2007 as Director of Technology with a particular focus on helping the Association drive forward standards and technologies including High Speed Packet Access (HSPA) mobile broadband, Long Term Evolution (LTE) standards and IP Multimedia Subsystem (IMS) as well as providing internal technical consultancy to GSMA’s Projects and Working Groups. Prior to joining the GSMA, Dan worked for Vodafone and Nortel. Dan has a degree in Mathematics and a PhD in Applied Mathematics.
