Japan’s NTT Docomo and China’s Huawei said today they have demonstrated that LTE can be deployed over unlicensed 5GHz spectrum — a breakthrough that could ultimately give operators complementary access to LTE bands to increase data speeds and cell capacity.
The research, carried out at a Huawei facility in Beijing over the past six months, used Licensed-Assisted Access (LAA) technology to expand LTE-compatible spectrum to the 5GHz band, which is widely used for wireless LANs in many countries. Currently, LTE’s compatible spectrum bands are licensed between the 700MHz and 2.5GHz bands in Japan.
The indoor test was able to boost cell capacity by about 1.6 times more than that of IEEE 802.11n, a standard specification for WLAN, a Docomo statement said.
The companies said the result was a positive indication that LAA can be used to speed up 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.”
Tolaga’s Chief Research Officer Phil Marshall told Mobile World Live that from a service provider’s perspective the extension of LTE-Advanced carrier aggregation into the unlicensed band is compelling and “quite an elegant solution”. But he said a few of the pieces need to come together.
“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,” he said.
Using carrier aggregation, Marshall said, operators can bolt on unlicensed spectrum, but their control channels work in the licensed band, removing issues of service continuity – a common problem with Wi-Fi.
The two companies added that the standardisation of LAA, which shows “great potential” as a solution for extremely condensed data traffic, is likely to be discussed later this year by 3GPP.