Multi-user MAC Protocol for WLANs in MmWave Massive MIMO Systems with Mobile Edge Computing

Merging mobile edge computing (MEC) service with the wireless local area networks (WLANs) provides enormous benefits such as intensive computation capabilities. Access to high-speed WLANs has become an urgent challenge due to the fast rate of application development and user adoption. Providing increased wireless resources is one solution, but millimeter (mmWave) multi-user massive Multiple-Input Multiple-Output (MIMO) technology has also attracted attention due to a series of features such as high throughput, strong anti-interference ability, and small fading. Hence, exploring the potential of mmWave MIMO systems for WLAN could play a significant role in improving network performance, especially throughput. In this paper, we introduce mmWave and massive MIMO into traditional WLAN with MEC, which enables a large portion of spatial resources to be allocated among users, and mitigates inter-user interference. Moreover, we propose a novel media access control (MAC) protocol, named as LSMWN-MAC, to adapt to a series of unique characteristics of mmWave and massive MIMO, which adopts space division multiple access (SDMA) as one of the resource methods, taking full advantage of spatial resources. In addition, we modify the protocol and propose the MLSMWN-MAC protocol to allocate resources dynamically, a solution that is particularly suitable for scenes with 30-50 users. Simulation results show that compared to 802.11ad, the proposed two protocols can increase the saturated throughput by 4.7Gb/s and 5.4Gb/s respectively, which are close to the throughput upper limit of the mmWave MIMO system. Meanwhile, we observe that when the number of users exceeds the threshold, the performance of the LSMWN-MAC protocol using a static allocation method is superior to the MLSMWN-MAC protocol using a dynamic method. In other cases, the dynamic protocol has better performances.