Mobile subscriptions are forecast to exceed the world's population in 2015, driving a significant growth in mobile data traffic, according to the Ericsson Mobility Report (June 2014).
Leading mobile operators are looking for innovative ways to increase the performance of their networks to handle this growth, while delivering a consistently great user experience.
To address these operator challenges, Ericsson, SingTel and Qualcomm Technologies have achieved an industry first with the live demonstration of FDD/TDD carrier aggregation using commercial track hardware and software. The demonstration achieved 260Mbps downlink speeds.
Tay Yeow Lian, managing director for networks at SingTel, said: "We are already using dual-layers of LTE FDD with LTE-Advanced carrier aggregation, and we know the performance of our mobile network is critical to ensuring that our customers have a great experience on their smartphones and tablets.
“Therefore, we will continue to explore the future option of bundling even TDD spectrum into the LTE carrier aggregation to expand network capacity, allowing our customers to enjoy consistent high data speed download even at high traffic areas. We are glad that Ericsson is making significant efforts to deliver innovations that keep us in the front position of such technology development.
“By working closely with Qualcomm Technologies, Ericsson is moving FDD/TDD carrier aggregation from a trial concept towards a commercial solution that we can plan to further differentiate our performance advantage in the future when the additional TDD spectrum is available."
The technical demonstration took place at the SingTel office in Singapore on 3 October 2014, utilising a Qualcomm Snapdragon 810 processor, a product of Qualcomm Technologies, and Ericsson high-performance LTE software designed to support the company's multi-standard RBS6000 family of base stations for macro and small-cell networks.
In the demonstration, Ericsson aggregated 20MHz of LTE FDD spectrum with 20MHz of LTE TDD spectrum, supporting peak data rates up to 260Mbps.
Serge Willenegger, vice president of product management, Qualcomm Technologies, said: "We are delighted to work with Ericsson and SingTel to deliver the latest LTE Advanced multimode solutions to the mobile industry. The Snapdragon 810 processor builds upon our leadership in LTE Advanced technology by supporting carrier aggregation across LTE TDD and LTE FDD."
FDD/TDD carrier aggregation
FDD/TDD carrier aggregation enables operators to complement their FDD networks with a cost-efficient deployment of TDD. For operators using TDD bands, the TDD uplink coverage can be a constraint. By combining TDD and FDD spectrum through carrier aggregation, low band FDD can deliver good uplink coverage while the TDD band can be leveraged for higher downlink capacity.
LTE FDD/TDD carrier aggregation enables spectrum from both LTE FDD and LTE TDD to be combined to deliver higher peak data speeds and improve app coverage across the network. It increases the effective TDD coverage area by up to 70%, reducing the cost of providing TDD coverage. It also ensures efficient utilisation of spectrum, increasing both the combined FDD/TDD coverage area and capacity of the network.
Per Narvinger, head of product area LTE at Ericsson, said: "We are pleased to have an opportunity to showcase our FDD/TDD carrier aggregation capabilities to SingTel together with Qualcomm Technologies. We demonstrated that the combination of low- to mid-band FDD with high band TDD can provide significant network performance gains. This complements the FDD/TDD interoperability work which we have already commercialised in countries where TDD spectrum is granted."
Ericsson also conducted earlier trials of this carrier aggregation approach over the summer, providing the groundwork for this latest achievement. Ericsson is working with mobile eco-system partners to support the full commercialisation of the LTE FDD/TDD carrier aggregation capability. Commercial devices supporting FDD/TDD carrier aggregation are expected in 2015.