Published: March 05, 2019
Yao Ma, Daniel G. Kuester, Jason B. Coder, William Young
To improve spectrum sharing between long-term evolution (LTE) license assisted access (LAA) and incumbent systems such as wireless local area networks (WLANs) in unlicensed spectrum, listen before talk (LBT) has been proposed as a candidate for LAA channel access. To allow a robust spectrum sensing performance, the LBT may use a backoff slot duration that is substantially larger than its WLAN counterpart. There is an unknown backoff slot-jamming (SJ) effect, which may significantly decrease channel access probability (CAP) and throughput of LAA-LBT links. In this paper, we study the SJ effect and propose an effective anti-SJ (ASJ) LBT scheme. To gain theoretical insight, we develop a new performance analysis approach on coexisting systems with different slot durations. We model the LAA backoff process with super-counters and provide an in-depth analysis of the backoff process, and derive statistics such as backoff hold time, successful transmission probability, CAP, and throughput. Simulation results thoroughly validate our analytical results, and show that the ASJ-LBT scheme is effective in mitigating the SJ effect. These results fill a major technical gap in spectrum sharing research and the new approach may be extended to coexistence analysis of other heterogeneous systems.
Citation: IEEE Transactions on Communications
Pub Type: Journals
CSMA/CA, LTE-LAA, MAC-layer Performance Analysis, Wireless Spectrum Sharing, WLAN.
Created March 05, 2019, Updated March 22, 2019