未来超密集无线网中海量内容传输技术的基础制约关系研究

Mobile Internet is developing rapidly every year, posing great challenges to the data capacity of modern wireless communication networks. Network densification is widely regarded as a key technology that answers the capacity challenge through better spectral reuse. However, the backhaul capacity limit is becoming the performance bottleneck of the system. Recently caching at the network edges is attracting great attention as an effective solution to this problem. In this project, we consider edge caching problems in Ultra Dense Networks (UDN), focusing on investigating theoretically the fundamental trade-offs therein. First a time-varying user demand model is investigated. Based on the demand model, we will analyze the trade-off between power consumption and backhaul capacity under D2D assisted caching, and the corresponding user incentive mechanisms. Besides, coded caching at base stations will be studied under UDN, and the trade-off between cache size, coding, and backhaul rate is analyzed. Furthermore, we will develop fusion mechanisms between various caching schemes under practical constraints of UDN, and investigate the corresponding trade-offs among key system parameters. The theoretical results of this project will greatly benefit the development of practical systems in the future.

移动互联网的迅猛发展对无线通信网络数据容量带来巨大挑战。部署超密集无线网实现高效频谱复用是提高网络容量的关键技术之一。然而其回传链路瓶颈问题日益突出。近期网络末端缓存作为一种有效解决回传链路瓶颈的技术得到广泛关注。本项目将以网络末端缓存为指导思想，以超密集无线网为具体应用场景，从理论层次深入研究缓存技术及其中存在的基础制约关系。首先项目通过建模提出用户行为的动态时变模型。利用此模型项目将分析D2D辅助缓存下用户能耗、回传链路容量与缓存容量之间的基础制约关系及用户激励机制。此外项目将研究适应时变用户请求的基站编码缓存方案及其中回传链路容量与编码及缓存容量的基础制约关系。最后项目将进一步探讨在超密集无线网络实际场景中，基站端缓存、用户端缓存、编码及D2D辅助等多项机制的融合技术，以及此系统中可能存在的基础制约关系。本项目的研究成果将对未来相关系统的实现及技术方案选择提供重要理论依据与科学指导。

移动互联网的迅猛发展对无线通信网络数据容量带来巨大挑战，回传链路瓶颈问题日益突出，网络末端缓存作为一种有效解决回传链路瓶颈的技术得到广泛关注。本项目以网络末端缓存为指导思想，以超密集无线网络为具体应用场景，从理论层次深入研究缓存技术及其中存在的基础制约关系。本项目通过建模提出并验证用户行为的动态时变模型、探究并分析D2D辅助缓存下用户能耗、回传链路容量与缓存容量之间的基础制约关系及用户激励机制，研究适应时变用户请求的基站编码缓存方案及其中回传链路容量与编码寄缓存容量的基础制约关系、探讨在超密集无线网络实际场景中，基站端缓存、用户端缓存、编码及D2D辅助等多项机制的融合技术，以及此系统中可能存在的基础制约关系。