基于网络MIMO协作的WIFI网络吞吐量提升理论与方法研究

Densely deployed WIFI access points (APs) have emerged widely in various hotspots. And users present daily increasing demand for higher bandwidth. However, due to channel interference, more AP resources do not bring expected larger network capacity. And, it becomes harder and harder for traditional conflict-avoidance based AP cooperative solutions, to effectively take use of the densely deployed APs, because of the radio broadcast characteristic. In contrast, network multi-input multi-output (MIMO) leans on interference alignment to resolve channel conflict, is a promising technology for promoting dense wireless network capacity in the future. In this project, we plan to research on the capacity-achieving network MIMO based multi-AP multi-user cooperative mechanism in dense WIFI networks. In details: Firstly, modeling and analyzing network MIMO cooperative transmission in WIFI networks, in order to clarify the effective throughput scaling characteristic of network MIMO in case of WIFI; Secondly, research on the network MIMO based AP partition, to address the lack of extensibility of network MIMO due to overhead, aiming to maximize the whole network capacity; Thirdly, research on network MIMO based inner-cluster multi user scheduling algorithm, to address the shortcomings of too many users and too much overhead required for user information exploration, so as to optimize the network MIMO throughput gain inside a cluster.

WIFI访问点部署越来越密集，用户对带宽需求越来越高。但因为信道干涉，资源增多并没有带来网络容量的预期增长。传统基于冲突避免的访问点协作机制，受限于无线广播特点，很难有效利用密集访问点资源。网MIMO技术通过干涉对齐，消解信道冲突，对提高密集无线网络容量展现出巨大潜力。本项目拟基于网络MIMO研究多访问点多用户协作机制，提升WIFI网络吞吐量。具体从以下三个方面展开：①针对网络MIMO多用于蜂窝网而少用于WIFI网的现状，建模分析WIFI网络中网络MIMO的协同传输过程，阐明WIFI网络中网络MIMO有效吞吐量增益的标度特性；②针对网络MIMO因开销较大导致扩展能力不足的问题，研究基于网络MIMO的WIFI访问点分簇方法，降低网络MIMO开销的同时提高全网容量；③针对用户较多、用户信息获取开销较大的问题，研究基于网络MIMO的簇内多用户调度算法，优化簇内网络MIMO协同传输的吞吐量增益。