LTE will be a major enhancement to 3G networks. It utilises a completely new modulation (for a 3G system) – OFDM – which has been widely adopted for WLAN (IEEE 802.11a/b/g), WiMAX, DVB digital terrestrial TV and DAB digital radio.
While LTE can support narrower bandwidths than HSPA/HSPA+ (supporting bandwidths as low as 1.5MHz), it is its use of wider bandwidths (up to 20MHz) that allows LTE to achieve substantial throughput advantages over HSPA/HSPA+.
LTE is designed to offer peak theoretical download rates of between 173Mbps and 326Mbps (depending on the number of MIMO antennas used) in 20MHz of spectrum. Theoretical peak upload speeds will be 86Mbps using 20MHz spectrum. All terminals should be able to operate using 20MHz of bandwidth to achieve the best performance possible from LTE.
The LTE Radio Access Network technical specification was approved in January 2008 and is being incorporated into 3GPP Release 8.
Most 3G operators with HSPA networks are expected to upgrade to LTE at some stage. In April 2009, the GSA (Global mobile Suppliers Association) announced that 31 operators had committed to LTE deployment. A number of 3G operators are expected to deploy LTE in 2010, which include:
- NTT DoCoMo and KDDI, in Japan
- Verizon Wireless, in the USA
- Rogers Wireless (in time for the 2010 Olympics) and Telus, in Canada
- TeliaSonera, in Sweden and Norway
- Tele3 and Telenor (which are jointly building an LTE network), in Sweden.