Search results for "Access method"

showing 3 items of 3 documents

A contention-based multiple access protocol in cooperative wireless networks

2010

Cooperative communication has emerged as a promising technique to enhance system performance in wireless networks. This paper proposes a contention-based cooperative multiple medium access control protocol by means of multiple retransmissions of the same packet from different relay nodes. The proposed scheme exploits cooperative communication capability not only from time diversity derived from multiple temporal transmissions but also spatial diversity derived from distributed multiple relays. A Markov chain is introduced to analyze the throughput performance of the proposed cooperative scheme. The performance evaluation of the protocol is validated and compared with non-cooperative ARQ pro…

Computer scienceWireless networkbusiness.industryNetwork packetDistributed computingAutomatic repeat requestComputerSystemsOrganization_COMPUTER-COMMUNICATIONNETWORKSThroughputAntenna diversityTime diversitylaw.inventionCooperative diversityRelaylawComputer Science::Networking and Internet ArchitectureChannel access methodbusinessComputer Science::Information TheoryCommunication channelComputer networkProceedings of the 6th International Wireless Communications and Mobile Computing Conference
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Optimal Resource Allocation in Multi-Hop Networks: Contention vs. Scheduling

2014

CSMA/CA (Carrier Sense Multiple Access/Collision Avoidance) is actually the most used method in ad-hoc networks for transmitting on a contending medium, even if it shows poor performance in presence of hidden nodes. To increase performance, we propose an algorithm that combines CSMA and TDMA (Time Division Multiple Access) approaches. The adopted solution consists of grouping contending nodes in non-interfering subsets and granting a different numbers of time slots to different groups, while using the CSMA to manage medium access among nodes belonging to the same subset. An optimization procedure to assign the time slots to each subset of nodes and to find an equilibrium between contention …

resource allocation; multi hop neworksSettore ING-INF/03 - TelecomunicazioniComputer sciencebusiness.industryDistributed computingMulti-frequency time division multiple accessComputerSystemsOrganization_COMPUTER-COMMUNICATIONNETWORKSTime division multiple accessresource allocationComputer Science Applications1707 Computer Vision and Pattern Recognitionmulti hop neworksHop (networking)Carrier-sense multiple accessScheduling (computing)resource allocation multi hop neworksComputer Networks and CommunicationSettore ING-INF/04 - AutomaticaControl and Systems EngineeringChannel access methodbusinessInformation SystemsComputer network
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No Reservations Required: Achieving Fairness between Wi-Fi and NR-U with Self-Deferral Only

2021

Wireless technologies coexisting in unlicensed bands should receive a fair share of the available channel resources, even when they use different access methods. We consider the problem of coexistence between Wi-Fi and New Radio Unlicensed (NR-U) nodes, which employ, respectively, a random and scheduled access scheme. The latter typically resorts to reservation signals (RSs), which allow keeping the control of the channel until the start of the next synchronized slot. This mechanism, although effective for increasing the channel access opportunities of scheduled-based nodes, is also a waste of channel resources. We investigate alternative solutions, based on self-deferral only. We built ana…

Scheme (programming language)business.industryComputer scienceRSSAccess methodReservationcomputer.file_formatRecurrent neural networkWirelessNetwork performancebusinesscomputerComputer networkcomputer.programming_languageCommunication channelProceedings of the 24th International ACM Conference on Modeling, Analysis and Simulation of Wireless and Mobile Systems
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