高密度部署的移动节点通信研究进展
周发升、范立生、罗高涌等
物联网研究团队论文题目为“A Cache-Aided Communication Scheme for Downlink Coordinated Multipoint Transmission”的研究成果在高水平期刊IEEE Access（JCR一区，影响因子：3.87）发表。在此同时，团队另外两项科研成果也分别被信息与通信领域权威期刊IET Communications（JCR三区，影响因子：1.023）和IEEE Communications Letters（JCR二区，影响因子：2.081）录用发表。
在这些研究工作中，物联网研究团队与清华大学等机构合作，针对未来高密度部署的移动节点不可靠通信问题，基于调度的边缘缓存技术对中断率进行改进；针对高密度节点信号强干扰问题，提出基于递归的波束成形，使信号波束准确发送到目标节点，有效降低一半干扰，从而可以有效提升未来移动网络的频谱效率和能源效率。
高密度移动物联网节点波束成形示意图
A Cache-Aided Communication Scheme for Downlink Coordinated Multipoint Transmission
Abstract: Content caching at the base stations (BSs) is a promising strategy that can provide improved quality-of-service (QoS) provisioning for content-centric services, and at the same time reduce instantaneous backhaul payload. In December 2017, Dr. Fasheng Zhou and his colleagues focus on applications of the caching mechanism in the downlink of coordinated multipoint (CoMP) transmission, where the collaborating BSs cooperatively serve the user equipments (UEs). The paper was accepted for publication by the journal IEEE Access. In this paper, a cacheaided transmission scheme for downlink CoMP with limited local cache resources at the BSs is proposed to improve QoS provisioning in terms of outage performance. In order to cache files more efficiently while guaranteeing the QoS, the contents are divided into two sets, a popular set and a less popular set, according to their popularity profile following the Zipf model. The popular files are cached at all the BSs, while the less popular files are cached only at part of the BSs in a cache cluster subject to the strategy design. Furthermore, based on popularity of the requested files, UEs are categorized into two groups and the notion of request competition between the two groups is introduced. The corresponding request competition model and admission probabilities for transmission requests are analyzed. Based on the request competition model, the best cache placement strategy for the popular and less popular sets that minimizes the average outage probability is derived. Numerical results show that the proposed cache-aided CoMP scheme outperforms the baseline traditional caching strategies in terms of the average transmission outage.
This work was coauthored by Dr Fasheng Zhou (1st), Dr. Lisheng Fan (2nd) and Dr. Gaoyong Luo (4th) from Guangzhou University, Dr. Ning Wang from Zhengzhou University, Dr. Jie Tang from South China University of Technology and Dr. Wei Chen from Tsinghua University.
