Performance Analysis of Licensed-Assisted Access Using LTE with Adaptive Carrier Selection

Licensed-Assisted Access (LAA) using Long Term Evolution (LTE) is a promising technique to extend the available bandwidth by aggregating the unlicensed spectrum. To guarantee fair co-existence of nodes deployed by different operators and different RATs, listen-before-talk (LBT) mechanism and carrier selection can be adopted by LAA as efficient candidates. In this paper, we provide insight into the LBT based LAA networks deployed by multiple operators using a hard core point process (HCPP) model. Moreover, an adaptive carrier selection scheme is developed where neighboring small cells select different carriers to avoid blocking each other so that larger number of active small cells can be retained after LBT channel sensing. The analytical results are developed in terms of active probability and coverage probability for single carrier, random carrier selection and the adaptive carrier selection scheme. It is revealed by numerical results that the number of active small cells can be significantly increased by employing adaptive carrier selection especially for large number of carriers, which further improves the network throughput.