Access point selection for improving the voice quality and overall throughput in wireless LANs

Abstract

IEEE 802.11 wireless LANs have been growing increasingly in recent years. In parallel with this, it is now easier for users to connect to access points (APs) which are commonly used. In IEEE 802.11 WLANs, a station can associate with more than one access point (AP). Previous algorithms which consider only the received signal strength indicator (RSSI) can cause stations to be associated to a single or only a few number of AP. However, it results in an overall network performance degradation. Besides, the multi-rate transmission opportunity over wireless networks can cause low bit rate stations to negatively affect high bit rate ones as well. Therefore, a new algorithm is required to select the best access point (AP) from a list of the users APs. In this paper, we propose a new AP selection algorithm which is based on perceived voice quality (R value), capacity utilization, transmission rate, fairness, hidden nodes and the number of associated stations to an AP. Proposed algorithm works efficient in the existence of both real-time and non-real-time traffic. Simulation results show improvements on the overall throughput and perceived voice quality. © 2011 Elsevier B.V., All rights reserved.