Carrier aggregation development, which has been accelerating in the last year, led to products that were all the rage at the Mobile World Congress 2014 in Barcelona. Each promises giant leaps in data throughput.
Huawei’s demonstration of LTE-Advanced FDD+TDD convergence carrier aggregation across FDD and TDD LTE modes and Vodafone’s involvement are particularly interesting, according to Steven Hartley, principal analyst at Ovum.
“The benefit of CA across FDD and TDD LTE is that operators can combine cheaper TDD spectrum with more traditional FDD spectrum to boost capacity and downlink speeds,” Hartley said.
The demonstration, involving three FDD carriers and one TDD carrier, produced a single user peak downlink speed of an eye-popping 500 Mbps.
“In this case where partners are promising more than 500 Mbps, the cost efficiencies for an operator of leveraging the full range of spectrum assets available is unquestionable, but most operators have so far shied away from the technical complexities involved,” Hartley said.
Using Huawei’s technology, Vodafone combined 50 megahertz of FDD spectrum in the 800-MHz, 1800-MHz and 2600-MHz bands with its 20 megahertz of TDD spectrum in the 2600-MHz band in Spain.
Carrier aggregation speeds contrast glaringly with Vodafone’s 1800-MHz and 2600-MHz commercial LTE services, which were rolled out at the beginning of 2013 with a peak speed of 150 Mbps/user.
SK Telecom Demo Combines Three Channels
SK Telecom demonstrated LTE-Advanced by aggregating three bands at the Mobile World Congress. The carrier aggregation technology demonstration combined three 20-megahertz channels to offer speeds of up to 450 Mbps.
The Barcelona demonstration was only the latest in a rapid-fire string of new LTE-Advanced features from SK Telecom since last June. On Jan. 20, the carrier unveiled a wireless system that aggregates a 20-megahertz band and two 10-megahertz bands, supporting speeds of up to 300 Mbps. In November 2013, SK Telecom achieved throughput of 225 Mbps by aggregating a bandwidth of 20 megahertz in the 1.8-GHz band and a 10-megahertz channel at 800 MHz. In August 2013, the carrier combined a 20-megahertz downlink and a 15-megahertz uplink in the 1.8-GHz band; and in June, it combined a 10-megahertz channel in the 1.8-GHz band and a 10-megahertz channel in the 800-MHz band.
CA in Finland
Broadcom, Finnish carrier Elisa, and Nokia Solutions and Networks have demonstrated LTE-Advanced carrier aggregation on a live commercial network. The test aggregated two 20-megahertz channels in the 1800-MHz band and the 2600-MHz band to reach speeds of 300 Mbps.
Ted Abrams, Abrams Wireless, said that carrier aggregation is a milestone in spectral efficiency. But because it is only included in the latest version, Release 10, of the LTE-Advanced standard, it will take time to be rolled out to all U.S. networks.
“This gives all operators, large and small, the opportunity to harvest spectrum from various bands and carry broadband traffic through the air with an aggregated, composite carrier. Most of the LTE equipment deployed in the U.S.A. is Release 9, so it will be a while before all networks incorporate the carrier aggregation features of LTE-A,” he wrote.