A Markov-Based Modelling with Dynamic Contention Window Adaptation for LAA and WiFi Coexistence

Licensed-Assisted Access (LAA) allows the operations on unlicensed spectrum for Long Term Evolution (LTE). In this paper, we propose a Markov-based analytical framework using the listen-before-talk (LBT) mechanism with dynamic contention window adaptation to investigate the performance of LAA-LAA and LAA-WiFi coexistence scenarios. Specifically, we introduce a Maximum Contention Window Timer Mechanism (MCWTM) to reduce the waste of resources and improve LAA coexistence performance. Furthermore, we derive the successful transmission probability and system backoff time under the two coexistence cases. Numerical results validate that the proposed dynamic contention window adaptation with MCWTM is effective in LAA-LAA coexistence scenario and can also improve LAA performance in LAA-WiFi coexistence scenario, compared with the static contention window mechanism.

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