Based on the License-Assisted Access (LAA) small cell architecture, the LAA coexisting with Wi-Fi heterogeneous networks provides LTE mobile users with high bandwidth efficiency as the unlicensed channels are shared among LAA and Wi-Fi. However, LAA and Wi-Fi interfere with each other when both systems use the same unlicensed channel in heterogeneous networks. In such a network, unlicensed band allocation for LAA and Wi-Fi is an important issue that may affect the quality of service (QoS) of both systems significantly. In this paper, we propose an analytical model and conduct simulation experiments to study four allocations for the unlicensed band: unlicensed full allocation (UFA), unlicensed time-division allocation (UTA), and UFA/UTA with buffering mechanism (UFAB and UTAB) for the LAA data packets. We evaluate the performance of these unlicensed band allocation schemes in terms of the acceptance rate of both LAA and Wi-Fi packet data in the LAA buffer queue. Our study provides guidelines for designing the channel occupation phase and the buffer size of the LAA small cell.

翻译：基于授权辅助接入（LAA）小基站架构，LAA与Wi-Fi共存的异构网络通过共享非授权信道为LTE移动用户提供高频谱效率。然而，当两种系统在异构网络中使用相同的非授权信道时，LAA与Wi-Fi会相互产生干扰。在此类网络中，LAA与Wi-Fi的非授权频段分配是影响两者服务质量（QoS）的关键问题。本文提出一种分析模型并通过仿真实验研究了四种非授权频段分配方案：非授权全分配（UFA）、非授权时分分配（UTA），以及采用缓冲机制的UFA/UTA方案（UFAB与UTAB）用于处理LAA数据包。我们通过LAA缓冲队列中LAA与Wi-Fi分组数据的接纳率评估这些非授权频段分配方案的性能。本研究为设计LAA小基站的信道占用阶段与缓冲区大小提供了理论指导。