下一代非授权频段网络（UB-NGNs）是当前学术界和工业界关注的重点。针对由“接入资源可用性”低和“资源分配可知性”差所导致的高密集场景下多用户多址接入（MU-MAC）性能严重受限的问题，本项目面向UB-NGNs提出多小区多关联协作的新思想，并研究基于多关联协作的MU-MAC接入方法。其核心是：一方面，用户关联到多个小区的接入设备，同时接受它们提供的接入服务，为资源优化分配提供更大的解空间；另一方面，多个接入设备间采用协作的方式共享资源分配相关信息，避免小区间资源分配的相互冲突。从而同时提升“接入资源可用性”和“资源分配可知性”，达到对MAC性能全局最优化的目的。本项目具体研究：多关联协作链路的建模与分析；多关联协作接入网络的区域容量/吞吐量的建模与分析；多关联协作接入网络资源分配算法；基于多关联协作的MU-MAC协议设计与优化。所提多关联协作思想具有一般性，可应用于各种类型的无线网络中。

The unlicensed band based next generation networks (UB-NGNs) attract great attention from both the academia and industry. Facing to the poor performance of multi-user MAC (MU-MAC) caused by the low access resource availability and resource allocation knowability under the high-dense deployment scenarios, this project proposes a new concept of multi-BSS (Basic Service Set) association and cooperation for UB-NGNs, and studies the corresponding MU-MAC technologies. The key idea is: on the one hand, the end users associate to multiple access devices and are supported by them, which enlarges the solution space for resource allocation; on the other hand, multiple access devices share the information of resource allocation through cooperation, which avoids the collision of resource allocation among multiple cells. Then, it improves both the access resource availability and resource allocation knowability, and achieves global optimization for resource allocation. This project studies the following technologies: modeling and analysis of multi-BSS associated and cooperative link, modeling and analyzing the area capacity and throughput of multi-BSS associated and cooperative access network, multi-user resource allocation algorithm, and designing and optimizing the MU-MAC protocol based on multi-cess associated and cooperative link. The proposed multi-BSS association and cooperation concept is general and can be applied to various types of wireless networks.