In millimeter wave (mmWave) communication systems, beamforming-enabled directional transmission and network densification are usually used to overcome severe signal path loss problem and improve signal coverage quality. The combination of directional transmission and network densification poses a challenge to radio access resource management. The existing work presented an effective solution for dense mmWave wireless local area networks (WLANs). However, this scheme cannot adapt to network expansion when it is applied directly to dense mmWave cellular networks. In addition, there is still room for improvement in terms of energy efficiency and throughput. Therefore, we firstly propose an efficient hierarchical beamforming training (BFT) mechanism to establish directional links, which allows all the small cell base stations (SBSs) to participate in the merging of training frames to adapt to network expansion. Then, we design a BFT information-aided radio access resource allocation algorithm to improve the downlink energy efficiency of the entire mmWave cellular network by reasonably selecting beam directions and optimizing transmission powers and beam widths. Simulation results show that the proposed hierarchical BFT mechanism has the smaller overhead of BFT than the existing BFT mechanism, and the proposed BFT information-aided radio access resource allocation algorithm outperforms the existing corresponding algorithm in terms of average energy efficiency and throughput per link.

中文翻译：

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密集毫米波蜂窝网络中基于优先级策略的高效无线接入资源管理方案

在毫米波（mmWave）通信系统中，通常使用启用波束成形的定向传输和网络致密化来克服严重的信号路径损耗问题并提高信号覆盖质量。定向传输和网络致密化的结合对无线电接入资源管理提出了挑战。现有工作为密集的毫米波无线局域网（WLAN）提供了有效的解决方案。但是，此方案直接应用于密集的毫米波蜂窝网络时，不能适应网络扩展。另外，在能量效率和生产量方面仍有改进的空间。因此，我们首先提出一种有效的分层波束形成训练（BFT）机制，以建立定向链路，允许所有小型基站（SBS）参与合并训练帧以适应网络扩展。然后，我们设计了一种BFT信息辅助无线电接入资源分配算法，通过合理选择波束方向并优化传输功率和波束宽度来提高整个mmWave蜂窝网络的下行链路能量效率。仿真结果表明，所提出的分层BFT机制比现有的BFT机制具有更小的BFT开销，并且在平均能量效率和每条链路的吞吐量方面，所提出的BFT信息辅助无线电接入资源分配算法优于现有的相应算法。我们设计了一种BFT信息辅助无线电接入资源分配算法，通过合理选择波束方向并优化传输功率和波束宽度来提高整个mmWave蜂窝网络的下行链路能量效率。仿真结果表明，所提出的分层BFT机制比现有的BFT机制具有更小的BFT开销，并且在平均能量效率和每条链路的吞吐量方面，所提出的BFT信息辅助无线电接入资源分配算法优于现有的相应算法。我们设计了一种BFT信息辅助无线电接入资源分配算法，通过合理选择波束方向并优化传输功率和波束宽度来提高整个mmWave蜂窝网络的下行链路能量效率。仿真结果表明，所提出的分层BFT机制比现有的BFT机制具有更小的BFT开销，并且在平均能量效率和每条链路的吞吐量方面，所提出的BFT信息辅助无线电接入资源分配算法优于现有的相应算法。