Priority Based Power Saving Mode in WLAN

Overview

According to employing Power Saving Mode (PSM) scheme or not, stations (STAs) in Wireless Local Area Networks can be classified into two categories: STAs using PSM (PSSTAs) and STAs staying in Active Mode (AM-STAs). In IEEE 802.11 standard, a PS-STA periodically wakes up and retrieves data buffered at the Access Point through contending with both other PS-STAs and AM-STAs for its PS-Poll's transmission. Although AM-STAs usually have no concern with energy, their contention degrades the energy efficiency of PS-STAs, which usually have life concern, by increasing the time duration for data retrieving and increasing the number of PS-STAs which contend throughout the whole beacon interval but get no access opportunity.