5 research outputs found

    Analysis of Frequency Channel Division Strategy for CSMA/CA with RTS/CTS Mechanism

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    International audience—In this work we study the collision probability, saturation throughput and statistical delay for the carrier sense multiple access collision avoidance (CSMA/CA) protocol with request to send and clear to send (RTS/CTS) mechanism in the case of frequency channel division. We propose in this paper a modified version of CSMA/CA-RTS/CTS to be compatible with the channel repartition technique and we prove that an important gain is introduced in terms of system performance especially for loaded networks. Simulations highlight that dividing the channel into independent sub-channels reduces drastically the RTS collision probability. Moreover, a gain in terms of saturation throughput and delay is shown especially in dense networks. Index Terms—Carrier senses multiple access/collision avoid-ance (CSMA/CA), Frequency channel division, RTS/CTS, MAC protocol

    Performance Evaluation Of Multiband CSMA/CA With RTS/CTS For M2M Communication With Finite Retransmission Strategy

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    International audienceM2M communication is information exchange between machines and machines without any human interaction. M2M commu-nication based on cellular network suffers from the extremely large number of devices in service coverage. In cellular network case, the large number of devices lead to communication problem caused by collisions between the senders. In this work we study the collision probability, saturation throughput and packet error rate for the carrier sense multiple access collision avoidance (CSMA/CA) protocol with request to send and clear to send (RTS/CTS) mechanism in the case of frequency band division. We propose in this paper a modified version of CSMA/CA-RTS/CTS to be compatible with the band repartition technique and we prove that an important gain is introduced in terms of system performance especially for loaded networks. Different backoff stage numbers with different finite retransmission limit values are investigated. Simulations highlight that dividing the RTS band into independent channels reduces drastically the RTS collision probability and in particular the packet error rate. A gain in terms of saturation throughput is also demonstrated especially in charged networks mode

    Exploiting multi-user diversity in wireless LANs with channel-aware CSMA/CA

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    © 2015 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.This paper presents a channel-aware access scheme for Carrier Sense Multiple Access with Collision Avoidance (CSMA/CA) aiming to take advantage of multi-user diversity and improve throughput, while supporting distributed and asynchronous operation. By dynamically adjusting the contention window of each station (STA) according to its channel state, this method prioritizes STAs that gain most from using a channel, and hence, enhances channel utilization in comparison with a simple random access scheme. To model the proposed Adaptive CSMA/CA (A-CSMA/CA) protocol, a three-dimensional Markov chain is developed. With the aid of such model, performance of the proposed A-CSMA/CA is analytically studied in terms of saturation throughput. Furthermore, illustrative results confirm that A-CSMA/CA significantly improves the throughput, specifically in a large network

    On The Dynamic Spectrum Access For Next Generation Wireless Communication Systems

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