Título:
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A proposal for an adaptive s-aloha access system for a mobile cdma environment
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Autor/a:
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Sallent Roig, José Oriol; Agustí Comes, Ramon
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Otros autores:
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Universitat Politècnica de Catalunya. Departament de Teoria del Senyal i Comunicacions; Universitat Politècnica de Catalunya. GRCM - Grup de Recerca en Comunicacions Mòbils |
Abstract:
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This paper presents a novel adaptive direct-sequence code-division multiple-access (DS-CDMA) slotted-ALOHA (S-ALOHA) packet random-access scheme with transmitter-based spreading codes for mobiles. It is aimed at improving throughput and message delay delivery when traffic load values below the saturation point of the conventional DS-CDMA S-ALOHA system are sensed in the channel. For this purpose, one mobile-station (MS) and two base-station (BS)-assisted algorithms are envisaged to control the change of the transmission rate according to the traffic load. These algorithms revealed that the optimum behavior, obtained using a Markov chain model, may almost be reached at a low-complexity cost. A traffic model based on a realistic statistical length distribution of the messages illustrates how the delay delivery can be greatly reduced with the proposed algorithms. Finally, the impact of forward-error-correction (FEC) coding on the adaptive system is also studied. |
Abstract:
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Peer Reviewed |
Materia(s):
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-Àrees temàtiques de la UPC::Enginyeria de la telecomunicació::Radiocomunicació i exploració electromagnètica::Comunicacions mòbils -Intelligent transportation systems -Forward error correction -Access protocols -Code division multiple access -Packet radio networks -Land mobile radio -Spread spectrum communication -Delays -Markov processes -Telecommunication traffic -Sistemes de transport intel·ligent |
Derechos:
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Tipo de documento:
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Artículo - Versión publicada Artículo |
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