dc.contributor
Universitat Politècnica de Catalunya. Departament de Teoria del Senyal i Comunicacions
dc.contributor
Universitat Politècnica de Catalunya. GRCM - Grup de Recerca en Comunicacions Mòbils
dc.contributor.author
Sallent Roig, Oriol
dc.contributor.author
Agustí Comes, Ramon
dc.identifier
Sallent, J., Agusti, R. A proposal for an adaptive s-aloha access system for a mobile cdma environment. "IEEE transactions on vehicular technology", Agost 1998, vol. 47, núm. 3, p. 977-986.
dc.identifier
https://hdl.handle.net/2117/117238
dc.identifier
10.1109/25.704852
dc.description.abstract
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.
dc.description.abstract
Peer Reviewed
dc.description.abstract
Postprint (published version)
dc.format
application/pdf
dc.relation
http://ieeexplore.ieee.org.recursos.biblioteca.upc.edu/document/704852/
dc.subject
Àrees temàtiques de la UPC::Enginyeria de la telecomunicació::Radiocomunicació i exploració electromagnètica::Comunicacions mòbils
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Intelligent transportation systems
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Forward error correction
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Access protocols
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Code division multiple access
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Packet radio networks
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Land mobile radio
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Spread spectrum communication
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Markov processes
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Telecommunication traffic
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Sistemes de transport intel·ligent
dc.title
A proposal for an adaptive s-aloha access system for a mobile cdma environment
