A novel cross-layer design for dynamic TXOP in IEEE802.11e

Abstract

Original scientific paper This paper proposes a novel framework for the cross-layer design and optimization of wireless networks combining adaptive modulation and coding (AMC) at the physical (PHY) layer by means of automatic repeat request and channel-aware multiuser scheduling protocols at the data link control (DLC) layer. The proposed framework is based on the use of two-dimensional discrete time Markov chains (DTMCs) jointly modelling the AMC scheme and the amplitude contention window (CW). A new algorithm for dynamic configuration of the polled transmission opportunity (TXOP) in multi-rate IEEE 802.11e network is presented and its performance is analysed and compared with default configuration. The numerical simulation results have indicated the high efficacy of the proposed method in maximizing the average throughput of the system. Keywords: Adaptive Modulation and Coding (AMC); cross-layer design; Hybrid Automatic Repeat Request (HARQ); Markov modelsNovi cross-layer projekt za dinamički TXOP u IEEE802.11eIzvorni znanstveni članak U radu se predlaže novi okvir za konstrukciju s poprečnim slojevima (cross-layer design) i optimizaciju bežičnih mreža kombiniranjem adaptivne modulacije i kodiranja (AMC) na fizičkom sloju (PHY) pomoću automatskog zahtjeva za ponavljanjem (automatic repeat request) i channel-aware multiuser scheduling protokola kod sloja za reguliranje povezivanja podataka -data link control (DLC). Predloženo se načelo zasniva na primjeni dvodimenzijskih Markovljevih lanaca diskretnog vremena -two-dimensional discrete time Markov chains (DTMCs) koji skupa modeliraju AMC shemu i amplitude contention window (CW). Predstavljen je novi algoritam za dinamičku konfiguraciju ispitivane mogućnosti prijenosa -polled transmission opportunity (TXOP) u IEEE 802.11e mreži s više brzina te se analizira njegova učinkovitost i uspoređuje sa zadanom konfiguracijom. Rezultati numeričke simulacije pokazali su visoku učinkovitost predložene metode u maksimiranju prosječnog protoka sustava. Ključne riječi: adaptivna modulacija i kodiranje (AMC); cross-layer konstrukcija; hibridni automatski zahtjev za ponavljanjem(HARQ); Markovljevi modeli