Global Sources
EE Times-Asia
Stay in touch with EE Times Asia
EE Times-Asia > RF/Microwave

What lies ahead for LTE?

Posted: 09 Mar 2011 ?? ?Print Version ?Bookmark and Share

Keywords:LTE? multimode radios? multifrequency? voice over? interference?

Broadband wireless technologies, particularly LTE, scored major feats in 2010. To date, 17 LTE networks are already operational and more than 64 operators in 31 countries have pledged their support for LTE. While the technology has made headway in terms of deployment, network carriers admit that enhancements and innovations must be introduced to enable customers to fully enjoy their LTE-enabled devices wherever they may use them. Aside from helping today's LTE networks perform better, these innovations will also take LTE to the next phase of its evolutionLTE Advanced.

A variety of issues need to be addressed, hence, network operators and handset OEMs can take full advantage of the performance benefits of LTE both now and in the future. Three issues of particular concern are multimode/multifrequency support, implementing voice over LTE and how networks will handle interference.

First, let's consider the different ways LTE is being implemented globally and how this will affect device OEMs looking to support the LTE standard. The radio frequencies used on LTE networks vary from region to region; there are currently over 20 different frequencies ranging from 700MHz to 2.6GHz that can be used by LTE networks around the world.

LTE networks

Click the image to enlarge.

In order to ensure that LTE supports global roaming and realizes the scale of a global technology, LTE smartphone and data card OEMs will need access to chipsets with multiband, multimode radios. These same chipsets must also be backward compatible with existing 3G technologies to provide a comparable experience in areas without LTE coverage or ubiquitous 3G. Supporting multiple technologies and frequency bands in a single chipset is hard enough, but making the chipset small enough and making sure the chipset has the right power management capabilities to provide all-day operation is a challenge that few mobile chipset providers are prepared to meet.

Another issue to be addressed is LTE support for voice. Today's LTE networks support data traffic only; smartphones can use LTE for data traffic, but must fall back on 3G technologies to provide simultaneous voice-and-data or voice-only connections. LTE Release 9 contains enhancements that will minimize the transition time from an LTE data session to a 3G voice call. Native voice support in future LTE networks will be provided using VoIP. To handle the stringent quality and coverage expectations of voice, LTE VoIP networks can seamlessly handover to 3G using the single radio voice call continuity (SRVCC) feature. One key advantage of the 3G fallback and voice continuity features of LTE is that they enable the support of tight voice interworking between LTE and 3G in a fully integrated "single radio" chipset. These single radio approaches to voice interworking will maximize the LTE user experience, reduce smartphone cost and extend battery life.

As data usage on mobile networks continues to become increasingly popular, LTE networks will also require the use of more cells with smaller coverage area per cell in order to handle the expected traffic load. But increasing the number of cells in a coverage area presents another problem: interference. Future releases of the LTE standard, specifically Release 10 (also called LTE Advanced), have been specifically designed to address the interference issue through the use of advanced network topologies and by leveraging a wider bandwidth frequency spectrum.

1???2?Next Page?Last Page

Article Comments - What lies ahead for LTE?
*? You can enter [0] more charecters.
*Verify code:


Visit Asia Webinars to learn about the latest in technology and get practical design tips.

Back to Top