Investigations in the Areas of Performance Improvement in WLAN Standard Over Existing WLAN and Cellular Networks

Abstract

The study have verified 802.11ac to be superior in performance compared to the newlineexisting WLANs. It is found that individual benefits from independent features newlinelike MCS, CBW, SS, TxBF and MU-MIMO are good and can aid in working newlinetowards QoS improvement. The performance of cellular networks with respect to QoS has been looked into newlineto identify areas differing from WLANs - the scheduler. The concept of a newlinescheduler is not specified by the IEEE WLAN standard unlike in cellular newlinenetworks such as LTE and WiMAX. Also, link adaptation is clearly defined in newlinemobile communications, whereas, RA mechanisms are loosely coupled to system newlineflow in WLANs. Also, approaches used in literature for applying scheduling techniques to newlineWLANs are analyzed. The scheduling approaches which have been recommended newlinefor WLANs and are based on the following layers / mechanisms: Traffic newlineScheduling schemes, Polling, Token Passing, MAC layer (Aggregation and newlineTXOP), PHY layer (scheduling using Resource Blocks), Cross platform and Out newlineof band approaches.Based on the above investigations (1 to 3), it is recommended to employ a newlinescheduler for 802.11ac for assuring QoS guarantees, a major issue since long. newlineMoreover, there is also a demand for schedulers based on the emerging newlineapplications and their QoS requirements. Additionally, there is a need to integrate newlineRA with the scheduler for performance improvement. With individual features, newlineperformance enhancement is modest but with a combination of the WLAN newlinefeatures we can hope for remarkable improvements. These combination and cross newlinelayer approaches are discussed. Scheduler is the ideal framework for managing newlineflows using these combined features - to achieve optimum QoS based on different newlinescenarios.