Improving wireless LAN throughput by using concurrent transmissions from multiple access points based on location of mobile hosts

Abstract

The size of data exchanged via the Internet and the number of Wi-Fi devices have been increasing, and the amount of data traffic will continue to increase in the future. Thus, ensuring the communication capacity of wireless LANs is one of the most important issues. By reducing communication coverage of each wireless LAN access point (AP) and densely deploying APs, it is possible to improve the communication capacity of the wireless LAN. However, the communication capacity decreases due to frequent interference between APs when they are densely deployed. If neighboring APs can use different channels, interference between APs can be avoided. However, if the number of available channels is limited, it is difficult to improve the communication capacity by increasing the density of APs. For further improving the communication capacity of wireless LANs, the management and control of the APs on the same channel is important. In this paper, we present an architecture in which multiple APs working on the same channel concurrently transmit frames avoiding interference to improve the throughput. In the architecture, a device called an aggregator is introduced. All APs are connected to the aggregator, and the aggregator is connected to a wired LAN. The aggregator schedules downstream frames so as to increase the number of concurrent transmissions from multiple access points to different STAs in the area. It calculates SINR of APs and mobile hosts, and schedules concurrent transmissions. To this end, the aggregator obtains the location of the mobile hosts through the visible light communication or some other means. When there is only downstream traffic, simulation results show that the proposed architecture improves the throughput about 10% compared to the normal IEEE 802.11 wireless LAN.