LTE Advance

In preparation for the next generation of wireless technology, called IMT-Advanced by the International Telecommunication Union (ITU), LTE-Advanced was standardized by 3GPP in Release 10 and Release 11.  In November 2010, the ITU ratified LTE-Advanced as IMT-Advanced. LTE-Advanced is  a further evolution of LTE, an OFDMA-based technology, specified in Release 8 and 9, which is supported by a tremendous ecosystem of manufacturers and operators worldwide, and has already proven itself to be the global next generation technology. 

It is expected that LTE-Advanced will first be commercially available in 2012, with wider deployments by 2015. LTE-Advanced will be both backwards- and forwards-compatible with LTE, meaning LTE devices will operate in newer LTE-Advanced networks, and LTE-Advanced devices will operate in older LTE networks.

3GPP is developing the following capabilities for LTE-Advanced:

• Wider bandwidth support for up to 100 MHz via aggregation of 20 MHz blocks
• Uplink MIMO (Two transmit antennas in the device)
• Downlink MIMO of up to 8 by 8
• Coordinated multipoint transmission (CoMP) with two proposed approaches: coordinated scheduling and/or beamforming, and joint processing/transmission.

The table below summarizes anticipated LTE-Advanced performance relative to IMT-Advanced requirements:

IMT-Advanced Requirements and Anticipated LTE-Advanced Capability.

(Source: Mobile Broadband Explosion: 3GPP Broadband Evolution to IMT-Advanced, Rysavy Research/4G Americas, September 2011)

In all cases, projections of LTE-Advanced performance exceed that of the IMT-Advanced requirements.

It is expected to be mid- to next decade before OFDMA-based systems like LTE have a large percentage of subscribers, and it could be well toward the end of the next decade before LTE-Advanced has a large subscriber base.

LTE will address the market needs of the next decade. After that, operators may deploy 4G networks using LTE-Advanced technology as a foundation.  As new spectrum becomes available, in the next decade, especially if it includes wide radio channels, then LTE-Advance will be the ideal technology for these new bands. Even in existing bands, operators are likely to eventually upgrade their LTE networks to LTE-Advanced to obtain spectral efficiency gains and capabilities.