Scanning methods and apparatus for mobile devices in wireless local area networks for reduced power consumption

Abstract

One illustrative method for reducing power consumption in a mobile communication device of a wireless local area network (WLAN) involves the steps of identifying a communication signal quality value between the mobile device and a wireless access point of the WLAN with which the mobile device is currently associated; determining an initial timer value based on a predefined relationship with the communication signal quality value where, as the communication signal quality value decreases, the initial timer value correspondingly decreases; initializing a scan trigger timer with the initial timer value and running the scarf trigger timer; and upon expiration of the scan trigger timer: causing a scanning operation to be performed for identifying one or more wireless access points in a coverage region; and repeating the acts of identifying, determining, initializing and running the scan trigger timer, and causing the scanning operation to be performed. Preferably, the mobile device operates to refrain from performing scanning operations altogether when the communication signal quality value is greater than a scan trigger threshold value. The scan trigger threshold value may be derived from or calculated based on a previously-received or last-sampled communication signal quality value of the wireless access point sampled at a time when the mobile device chose to reassociate with a different wireless access point of the WLAN.