Research conducted by Huawei and NTT Docomo has demonstrated that LTE can be successfully deployed using unlicensed 5GHz spectrum.
This development could potentially allow operators to access LTE bands in addition to those that they hold licences for, enabling them to boost cell capacity and data speeds.
By using Licensed-Assisted Access (LAA) technology, the research – conducted at a Huawei facility – succeeded in making spectrum in the 5GHz band suitable for LTE. In Japan, LTE-compatible spectrum is licensed between the 700MHz and 2.5GHz bands, while the 5GHz band is used for wireless LANs in many countries.
Docomo has stated that the indoor test increased cell capacity by roughly 1.6 times that of IEEE 802.11n, which is a widely used WLAN specification. This result indicates that LAA is a viable option for increasing the speed of LTE and LTE-Advanced networks.
“For example, higher-speed data communications and a higher cell capacity in dense traffic areas should be achievable using 5GHz spectrum for LTE and LTE-Advanced on a complementary basis in coexistence with wireless LANs”, said the statement.
Using the unlicensed band for LTE-Advanced carrier aggregation was deemed “an elegant solution” by Phil Marshall, Chief Research Officer at Tolaga. However, he noted that this was only the first step.
“The challenge is in fuelling the ecosystem. For this reason the involvement of additional ecosystem players is significant — particularly in terms of service providers and device manufacturers,” said Marshall.
Operator control channels will continue to use the licensed band, but they will also be able to use the unlicensed spectrum via carrier aggregation, which will provide smoother continuity of service.
