Fading characteristics for indoor wireless channels at 5 GHz unlicensed bands

Today, Wi-Fi networks can be found almost everywhere: in homes, businesses, hotels, restaurants, transportation, streets, etc. Research subject. In this study, we analyze the performance of outdoor and indoor wireless local area networks. Method. To achieve this goal, the following empirical research methods were used: measurement, experiment, and comparison. Core results. In the first part of the study, experimental data on radio frequency spectrum usage around and inside St. Petersburg State University of Telecommunications are provided. The second part of the study is devoted to the peculiarities of outdoor and indoor Wi-Fi. The effective data rate, retry rate, and noise floor are compared for the 2.4 and 5 GHz frequency bands. Practical relevance. The obtained results can be used for design and optimization of outdoor Wi-Fi networks.

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APPLYING GAME THEORY IN 802.11 WIRELESS NETWORKS / ŽAIDIMŲ TEORIJOS TAIKYMAS IEEE 802.11 TINKLUOSE

Mokslas - Lietuvos ateitis ◽

10.3846/mla.2015.797 ◽

2015 ◽

Vol 7 (3) ◽

pp. 345-349

Author(s):

Tomas Cuzanauskas ◽

Aurimas Anskaitis

Keyword(s):

Game Theory ◽

Ieee 802.11 ◽

Interference Mitigation ◽

Low Cost ◽

Maximum Power ◽

Wireless Devices ◽

Unlicensed Spectrum ◽

Simple Rules ◽

Unlicensed Bands ◽

5 Ghz

IEEE 802.11 is one of the most popular wireless technologies in recent days. Due to easiness of adaption and relatively low cost the demand for IEEE 802.11 devices is increasing exponentially. IEEE works in two bands 2.4 GHz and 5 GHz, these bands are known as ISM band. The unlicensed bands are managed by authority which set simple rules to follow when using unlicensed bands, the rules includes requirements as maximum power, out-of-band emissions control as well as interference mitigation. However these rules became outdated as IEEE 802.11 technology is emerging and evolving in hours the rules aren’t well suited for current capabilities of IEEE 802.11 devices. In this article we present game theory based algorithm for IEEE 802.11 wireless devices, we will show that by using game theory it’s possible to achieve better usage of unlicensed spectrum as well as partially decline CSMA/CA. Finally by using this approach we might relax the currently applied maximum power rules for ISM bands, which enable IEEE 802.11 to work on longer distance and have better propagation characteristics. Lengvai pritaikoma ir panaudojama įvairiuose sprendimuose IEEE 802.11 technologija tapo viena populiariausių bevielių technologijų. IEEE 802.11 įrenginiai veikia nelicencijuotais 5 GHz ir 2,4 GHz dažniais – pramonės, mokslo ir medicinos dažnių ruože (angl. Industrial, scientific and medical (ISM) radio bands). Šiam dažnių ruožui taikomos supaprastintos taisyklės, nurodančios, kad įrenginiai, veikiantys ISM dažniais, turi atitikti tik maksimalią signalo perdavimo galią ir interferencijos triukšmus bei neviršyti triukšmo normos už dažnių ruožo ribų. Tobulėjant IEEE 802.11 protokolo įrangai, šios taisyklės tapo nelanksčios ir neatitinka dabartinių įrenginių galimybių. Straipsnyje pristatomas naujas IEEE 802.11 įrenginių kanalo prieigos metodas, pagrįstas žaidimų teorija. Parodoma, kad taikant šį metodą galima pagerinti spektro panaudojimo efektyvumą bei kartu iš dalies atsisakyti dabar egzistuojančio CSMA/CA mechanizmo IEEE 802.11 įrenginiuose. Taikant efektyvesnį kanalo prieigos metodą atsiranda galimybė laikytis lankstesnių siųstuvo galių taisyklių ir taip padidinti skvarbą uždarose patalpose bei įrangos veikimo nuotolį.

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