A Hybrid Access Scheme in LTE Licensed Assisted Access Networks

In order to deploy Long Term Evolution (LTE) on the unlicensed spectrum, Licensed-Assisted Access (LAA) has been proposed by 3rd Generation Partnership Project (3GPP). Since LAA is not the only technology deploying on the unlicensed band, an urgent issue for improving the performance of LAA is reducing the influence of interference from WiFi networks. Common access methods such as scheduling access and random access are not suitable for LAA and WiFi coexistence system since the radio channels may be occupied by other technologies meanwhile. To ensure the quality of service and improve the utilization of spectrum resource in LAA networks, a hybrid access scheme is proposed for uplink transmission in this paper. The hybrid access scheme can select an access scheme in each subframe between the scheduling based access scheme and the random access scheme taking the load condition of the networks into account. By the means of choosing the suitable access scheme dynamically, the hybrid access scheme may improve the access success rate of UE, which is superior to the random access scheme and the scheduling access scheme.