43documents trouvés
An Opportunistic Indoors Positioning Scheme Based on Estimated Positions
G. KANG, T.PERENNOU, M.DIAZ
ISAE, OLC
Manifestation avec acte : IEEE Symposium on Computers and Communications (ISCC 2009), Sousse (Tunisie), 5-8 Juillet 2009, pp.844-850 , N° 09820
Lien : http://hal.archives-ouvertes.fr/hal-00388801/fr/
Diffusable
120475Barycentric location estimation for indoors localization in opportunistic wireless networks
G.KANG, T.PERENNOU, M.DIAZ
Xi'an, OLC
Manifestation avec acte : 2nd International Conference on Future Generation Communication and Networking (FGCN 2008), Sanya (Chine), 13-15 Décembre 2008, 6p. , N° 08621
Diffusable
116345Reducing retransmissions in point-to-point satellite transmissions
J.LACAN, T.PERENNOU
OLC
Manifestation avec acte : 26th AIAA International Communications Satellite Systems (ICSSC 2008), San Diego (USA), 10-12 Juin 2008, 13p. , N° 08857
Lien : http://hal.archives-ouvertes.fr/hal-00395673/fr/
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Abstract
This paper presents a mechanism that reduces the number of retransmissions needed to ensure reliable unicast transmissions over a shared broadcast channel. This improves the bandwidth occupancy by information packets and potentially reduces the end-to-end jitter and delay. After each block transmission, the mechanism determines the minimal set of information packets to retransmit, builds a speci c Reed-Solomon code from this set and then sends repair packets produced with this code instead of retransmitting the information packets. The mechanism was analysed theoretically and evaluated numerically under many di erent conditions (variable packet loss rate, number of receivers, etc.). Both the erasure channel and the error channel were explored. In most cases, the system can be set up such that it uses less retransmissions than a classical ARQ mechanism: most of the time, 40% up to 95% less. Such a mechanism is clearly useful in satellite contexts.
KauNet: improving reproducibility for wireless and mobile research
J.GARCIA, E.CONCHON, T.PERENNOU, A.BRUNSTROM
Karlstad, OLC
Manifestation avec acte : MobiEval : System Evaluation for Mobile Platforms (MobiEval 2007), Puerto Rico (USA), 11 Juin 2007, pp.21-26 , N° 07839
Lien : http://hal.archives-ouvertes.fr/hal-00388795/fr/
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Abstract
This paper presents the KauNet emulation system that provides pattern-based emulation. KauNet enables bit precise placement of bit-errors, exact and repeatable packet losses, delays and bandwidth variations. The design and performance of KauNet is discussed. An example is also provided of how it can be integrated in a specific emulation framework to enhance emulation for mobile and wireless systems.
Improved IP-level emulation for mobile and wireless systems
E.CONCHON, J.GARCIA, T.PERENNOU, M.DIAZ
OLC, Karlstad
Manifestation avec acte : 2007 IEEE Wireless Communications & Networking Conference (WCNC'2007), Hong Kong (Chine), 11-15 Mars 2007, 6p. , N° 06641
Diffusable
109460A DCCP congestion control mechanism for wired-cum-wireless environments
I. H.NAQVI, T.PERENNOU
OLC
Manifestation avec acte : 2007 IEEE Wireless Communications & Networking Conference (WCNC'2007), Hong Kong (Chine), 11-15 Mars 2007, 6p. , N° 06663
Lien : http://hal.archives-ouvertes.fr/hal-00327080/fr/
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Abstract
Existing transport protocols, be it TCP, SCTP or DCCP, do not provide an efficient congestion control mechanism for heterogeneous wired-cum-wireless networks. Solutions involving implicit loss discrimination schemes have been proposed but were never implemented. Appropriate mechanisms can dramatically improve bandwidth usage over the Internet, especially for multimedia transport based on partial reliability. In this paper we have implemented and evaluated a congestion control mechanism that implicitly discriminates congestion and wireless losses in the datagram congestion control protocol (DCCP) congestion control identification (CCID) framework. The new CCID was implemented as a NS-2 module. Comparisons were made with the TCP-like CCID and showed that the bandwidth utilization was improved by more than 30% and up to 50% in significant setups.
Mots-Clés / Keywords
Losses; Internetworking; Wireless LAN; Protocols;
Evaluation of error control mechanisms for 802.11b multicast transmissions
J.LACAN, T.PERENNOU
OLC
Manifestation avec acte : 2nd International Workshop on Wireless Network Measurement (WiNMee'2006), Boston (USA), 3 Avril 2006, 6p. , N° 06072
Diffusable
106783Improving the reliability of point-to-point transmissions on a broadcast channel
J.LACAN, T.PERENNOU
OLC
Rapport LAAS N°06071, Janvier 2006, 14p.
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105815Evaluation de mécanismes de contrôle d'erreur pour des transmissions multipoints sur des réseaux de mobiles
T.PERENNOU, J.LACAN, H.EL NATOUR
TESA, ENSICA, OLC
Revue Scientifique : Technique et Science Informatiques, Vol.24, N°7, pp.865-886, 2005 , N° 04220
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105793A feedback based solution to emulate hidden terminals in wireless networks
E.CONCHON, T.PERENNOU, M.DIAZ
OLC
Manifestation avec acte : Symposium on Future Wireless Systems, Split (Croatie), 15-17 Septembre 2005, 5p. , N° 05475
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