Licensed Assisted Access (LAA) involves the integration of WLANs into LTE mobile networks in order to be able to communicate via the license-free frequency bands of the WLANs. Similar technical approaches are LTE-WAN Aggregation (LWA), LTE Unlicensed (LTE-U), LTE WLAN Radio Level Integration (LWIP) and MulteFire
(LTE-AP). The LAAapproach uses carrier aggregation in the downlink
and combines license-free frequency bands in the 5 GHz range with LTE frequency bands that require alicense.
Carrier aggregation provides a wider band of spectrum for higher data rates and faster user applications. The LAA concept works with the Listen Before Talking (LBT) access mechanism and thus checks whether the carrier frequency is occupied by other services. In this way, Long Term Evolution (LTE) can coexist with WiFi.