Antti Sorri

Enabling Frequency Reuse for Licensed-Assisted Access with Listen-Before-Talk in Unlicensed Bands

Licensed-Assisted Access (LAA) which allows LTE to be deployed in unlicensed spectrum is a promising technique currently under standardization in 3GPP Rel-13. To guarantee a peaceful coexistence of LAA with the incumbent systems such as WiFi, listen-before-talk (LBT) which requires the node to sense the medium before data transmission is introduced. On the other hand, LBT also prevents simultaneous transmission from neighbouring nodes of the same LAA operator. In order to increase the spectral efficiency of LAA, frequency reuse for transmission by neighbouring nodes of the same operator has been agreed to be one target of LAA design. In this paper we evaluate the performance of LAA in an indoor scenario assuming both one and two LAA networks deployed by different operators. It is shown that LBT is indeed needed to ensure good performance with multiple LAA operators, especially at high load. And frequency reuse between neighbouring nodes of the same LAA operator can further improve the performance.