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Browsing by Issue Date, starting with "2005-11"

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  • Planning of an IEEE 802.16e Network for Emergency and Safety Services
    Publication . Velez, Fernando José; Caravalho, Vitor; Santos, Dany; Marcos, Rui P.; Costa, Rui; Sebastião, Pedro; Rodrigues, António
    An overlaid Wimax cellular structure is proposed for emergency and safety services, with micro-cells covering urban hotspots over a macro-cellular structure. In the region of Beira Interior the process of cellular planning has to account for carrier-to-noise-interference ratio. Sectorisation is used in order to reduce reuse patterns and increase system capacity, while cell overlay is proposed to overcome coverage problems in large towns and cities. Geographic Information Systems tools are considered for Line-of-Sight discovery, and ~75% of LoS coverage is guaranteed in the city of Covilhã. The point-to-point component is also being incorporated in the planning tool. By comparing the 3.5GHz and the 5.8GHz bands one concludes that it is possible to use lower values of the antenna gains in the first case.
    2005-11Conference object Open access Show more
  • Optimisation of Indoor Mobile B3G Systems Based in Economic Aspects
    Publication . Cabral, Orlando Manuel Brito; Velez, Fernando José; Hadjipollas, George; Stylianou, Marinos; Antoniou, Josephine; Vassiliou, Vasilis; Pitsillides, Andreas
    System capacity results are obtained by using a system level simulator which considers traffic characterisation parameters and services usage, among other, in an offices scenario. Results for the most profitable cell radius are obtained via an optimisation procedure based in economic aspects. A higher number of pico cells (with a smaller radius, around 30-32 m) can be installed in the future when costs of deploying and maintaining the network decreases, allowing for supporting higher system capacity, and reducing prices. The impact of call blocking, handover failure, end-to-end delay, and delay variation are taken into account.
    2005-11Conference object Open access Show more
  • Cost/Revenue Optimisation of Enhanced UMTS Cellular Planning in Urban Scenarios
    Publication . Franco, Cátia; Rei, Ricardo; Velez, Fernando José
    Based in a definition of simulations scenarios, traffic behaviour, and QoS (Quality of Service) aspects, a SLS (System Level Simulator) is used for obtaining system capacity results for urban scenarios, when overload conditions are considered. Optimum values of the cell coverage distance that maximise the profit by unit area were found. For prices of 5 and 7 Euro cents/MB, optimum values of 70 % and 140 %, respectively, were found for profit (for a coverage distance of ~414 m).
    2005-11Conference object Open access Show more