While LTE services and related business models are still at a very nascent stage of development, the industry is already getting excited about the prospects of LTE-Advanced, particularly its key feature – carrier aggregation.
While wireless operators continue to seek high-performance and cost-effective solutions to support high-speed data services and cope with the explosive traffic demand, several questions come to mind when evaluating the benefits and costs of deploying carrier aggregation (CA):
- Is the bandwidth offered by current LTE networks enough?
- Is carrier aggregation all about higher bandwidth?
- Which operators will be the first to adopt the technology and why?
Are mobile handsets and chipsets ready for this challenge?
This article will provide some broad answers to these questions; more detailed and quantitative analysis will follow in a separate study.
The advantage of high-speed data rates
Last month, I had the privilege of visiting the R&D labs of leading players in the mobile handset industry and saw demonstrations of some of the technology innovations they have in the pipeline.
These innovations are emerging in every part of the supply chain – displays, multimedia processing, computational imaging, camera hardware, sensors, combo connectivity and so on – and I am now even more convinced that mobile devices will soon take the central role in the user entertainment system.
They will mutate from being phone-centric devices to become always-on computing and media hubs capable of accommodating Ultra-HD and 4K content, multichannel HD sound, augmented reality, contextual applications and a number of other bandwidth-hungry services.
However, the current cellular networks – including LTE – are not yet configured to carry the volume of traffic generated by such sophisticated and bandwidth-demanding applications and services.
Although current LTE networks support up to 20 MHz bandwidth for a single channel, only a few operators have been granted such a wide spectrum, the majority have so far been allocated channels with bandwidth that does not exceed 10 MHz.
Even for those lucky operators that have secured 20 MHz or more for LTE, this bandwidth often comes in the form of multiple and non-contiguous channels- two separated 10 MHz carrier components for example. This means that the bandwidth cannot be fully exploited to carry the superfast traffic generated by next-generation services.