The IEEE 802.11ad standard extends WiFi operation to the millimeter wave frequencies, and introduces novel features concerning both the physical (PHY) and Medium Access Control (MAC) layers. The hybrid MAC layer provides for two different kinds of resource allocations: Contention Based Access Periods (CBAPs) and contention-free Service Periods (SPs). In this paper, we propose a Markov Chain model to represent CBAPs, taking into account operation interruptions due to scheduled SPs and the deafness and hidden node problems that directional communication exacerbates. We also propose a mathematical analysis to evaluate the interference among stations and derive analytical expressions to assess the impact of various system parameters on some key performance metrics such as throughput, delay, and packet drop rate. This information may be used to efficiently design a transmission scheduler that allocates contention-based and contention-free periods based on the application requirements.

中文翻译：

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IEEE 802.11ad 中 CBAP 分配的分析模型

IEEE 802.11ad 标准将 WiFi 操作扩展到毫米波频率，并引入了有关物理 (PHY) 和媒体访问控制 (MAC) 层的新功能。混合 MAC 层提供两种不同类型的资源分配：基于竞争的访问周期 (CBAP) 和无竞争服务周期 (SP)。在本文中，我们提出了一个马尔可夫链模型来表示 CBAP，考虑到由于调度的 SP 导致的操作中断以及定向通信加剧的耳聋和隐藏节点问题。我们还提出了一种数学分析来评估站点之间的干扰，并推导出分析表达式来评估各种系统参数对一些关键性能指标的影响，例如吞吐量、延迟和丢包率。