T-Mobile US and Nokia have achieved download speeds of 1.3Gbps using Licensed Assisted Access (LAA). The vendor notes that its commercially-available AirScale platform was able to support 14-layer transmissions during the trials. The test combined licensed and unlicensed spectrum in a five-component carrier aggregation (CA) configuration, as well as using 256QAM and 4×4 MIMO functionality. (While the breakdown of spectrum has not been disclosed, T-Mobile has previously aggregated two licensed carrier channels and three unlicensed carrier channels during LTE-LAA testing.)
Neville Ray, chief technology officer at T-Mobile US, commented: ‘We are working to deploy small cells that support LAA and build on the LTE-A features we’ve deployed across the country, laying a foundation for 5G.’
TeleGeography notes that LTE-LAA was standardised by industry body the 3GPP (as part of Release 13). It uses CA in the downlink to combine LTE technology using unlicensed spectrum (5GHz band) with LTE in the licensed band. It has been suggested that a mobile operator using LAA can support Gigabit Class LTE using as little as 20MHz of licensed spectrum.