Qualcomm and Deutsche Telekom (DT) recently demonstrated LTE Licensed-Assisted Access' (LAA) ability to extend coverage and increase network capacity by aggregating licensed and unlicensed spectrum bands. The test also delivered seamless mobility andensured a fair coexistence with Wi-Fi in unlicensed spectrum.
"LAA is one of the key technologies that will help satisfy the increasing demand for data and better mobile connectivity," said Bruno Jacobfeuerborn, chief technology officer, Deutsche Telekom. "The trial will help the wireless ecosystem and key stakeholders verify and experience the benefits of LAA first hand."
"This trial is an important milestone demonstrating how global LAA technology will soon provide enhanced consumer benefits to users in Europe," said Matt Grob, executive vice president and chief technology officer, Qualcomm Technologies, Inc. "We are pleased to collaborate with Deutsche Telekom on testing and demonstrating technologies that will enhance mobile broadband."
LAA extends the benefits of 4G LTE Advanced to unlicensed spectrum bands, and is one of the new features of LTE Advanced Pro standards being developed in 3GPP Release 13, which is expected to be ready in the first half of 2016. The aggregation of licensed and unlicensed spectrum is another step in the evolution of 4G LTE towards development of a unified 5G platform, envisioned to offer native support for aggregation of unlicensed spectrum right from the start.
The over-the-air trial was completed on 20 November 2015, in Nuremberg, Germany after a three-week period of extensive measurement campaigns. The trial used LAA test equipment designed and deployed by Qualcomm Research, the R&D division of Qualcomm Technologies. Deutsche Telekom provided the licensed spectrum for the LTE anchor carrier augmented with 5 GHz unlicensed spectrum and used on a multiple node LAA test network deployed over Qualcomm Technologies' Nuremberg campus.
The team measured and demonstrated LAA's extended coverage and increased network capacity in utilizing unlicensed spectrum compared to Wi-Fi, as well as smooth and opportunistic aggregation of unlicensed spectrum during drive tests which also included seamless inter-eNB handovers. The fair coexistence between LAA and Wi-Fi in unlicensed 5 GHz bands was also demonstrated under different radio interference conditions and for a varied number of interfering nodes.
The LAA test equipment complies with current 3GPP Release 13 development and is particularly designed to meet global unlicensed band regulations, including "Listen-Before-Talk" features using Clear Channel Assessment Procedures and channel occupancy limits required in regions such as Europe and Japan. Fair spectrum usage between LAA links and Wi-Fi links was maintained for all coexistence test scenarios during the trial.