I. Introduction
THE variable channel-width technology is recently proposed to improve the performance of WLAN in terms of fairness and capacity [1],[2]. In Variable channel-width WLANs (V-WLANs), the total available spectrum is partitioned into several channels with variable widths, and hence channel allocation in V-WLANs is more flexible and efficient than those in traditional WLANs. Although channel allocation in V-WLANs has been investigated in the literature [2] [3], the AP selection problem remains open for V-WLANs. The variability of channel-widths of V-WLANs poses two new challenges to AP selection. First, the channel-width of an AP should be taken into account since it affects the bandwidth obtained by associated stations. Second, energy consumption for using a channel may vary depending on the channel width [1]. In this letter, we propose a distributed approach for a desired AP selection outcome. It is noted that the variability of channel-widths provides the network with a tuning capability to satisfy different quality of service (QoS) requirements. And the QoS requirement of each station is therefore considered in this study.