Search results for "52"
showing 10 items of 1043 documents
The Influence of LOS Components on the Statistical Properties of the Capacity of Amplify-and-Forward Channels
2009
Also available from publisher: http://dx.doi.org/10.4236/wsn.2009.11002 Amplify-and-forward channels in cooperative networks provide a promising improvement in the network coverage and system throughput. Under line-of-sight (LOS) propagation conditions in such cooperative networks, the overall fading channel can be modeled by a double Rice process. In this article, we have stud-ied the statistical properties of the capacity of double Rice fading channels. We have derived the analytical expressions for the probability density function (PDF), cumulative distribution function (CDF), level- crossing rate (LCR), and average duration of fades (ADF) of the channel capacity. The obtained results ar…
Parameter optimization for amplify-and-forward relaying systems with pilot symbol assisted modulation scheme
2009
Article published in the journal:Wireless Sensor Network Also available from publisher: http://dx.doi.org/10.4236/wsn.2009.11003 Cooperative diversity is a promising technology for future wireless networks. In this paper, we consider a cooperative communication system operating in an amplify-and-forward (AF) mode with a pilot symbol assisted modulation (PSAM) scheme. It is assumed that a linear minimum mean square estimator (LMMSE) is used for the channel estimation at the receiver. A simple and easy-to-evaluate asymptotical upper bound (AUB) of the symbol-error-rate (SER) is derived for uncoded AF cooperative communication systems with quadrature amplitude modulation (QAM) constellations. …
An Integrated Wireless Communication Architecture for Maritime Sector
2011
Published version of a chapter in the book: Multiple Access Communications. Also available from the publisher at http://dx.doi.org/10.1007/978-3-642-23795-9_17 The rapid evolution of terrestrial wireless systems has brought mobile users more and more desired communication services. Maritime customers are asking for the same, such as the concepts of “Broadband at Sea” and “Maritime Internet”. Quite a lot of research work has focused on the development of new and better maritime communication technologies, but less attention has been paid on interworking of multiple maritime wireless networks or on satisfying service provisioning. To address this, an integrated wireless Communication Architec…
UPnP control point for mobile phones in residential networks
2006
Together, Ericsson and HiA are studying the role of WiFi-enabled mobile phones in residential networks. This article describes a first step to allow mobile phones to discover and control networked residential media servers and renderers following the standards developed by the UPnP Forum.
A Single radio based channel datarate-aware parallel rendezvous MAC protocol for cognitive radio networks
2009
©2009 IEEE. Personal use of this material is permitted. However, permission to reprint/republish this material for advertising or promotional purposes or for creating new collective works for resale or redistribution to servers or lists, or to reuse any copyrighted component of this work in other works must be obtained from the IEEE. Article also available from publisher: http://dx.doi.org/10.1109/LCN.2009.5355152 Channel hopping based parallel rendezvous multichannel MAC protocols have several advantages since they do not need a control channel, require only one transceiver, and produce higher system capacity. However, channel hopping sequences in existing parallel rendezvous MAC protocols…
Cooperative RTS/CTS MAC with relay selection in distributed wireless networks
2009
©2009 IEEE. Personal use of this material is permitted. However, permission to reprint/republish this material for advertising or promotional purposes or for creating new collective works for resale or redistribution to servers or lists, or to reuse any copyrighted component of this work in other works must be obtained from the IEEE. Article also available from publisher: http://dx.doi.org/10.1109/ICUMT.2009.5345396 This paper proposes a cooperative multiple access protocol based on the distributed coordination function (DCF) request-to-send/clear-to-send (RTS/CTS) scheme for distributed wireless networks. It answers three key questions concerning cooperation from the network perspective, n…
Cooperative medium access control in wireless networks: The two-hop case
2009
©2009 IEEE. Personal use of this material is permitted. However, permission to reprint/republish this material for advertising or promotional purposes or for creating new collective works for resale or redistribution to servers or lists, or to reuse any copyrighted component of this work in other works must be obtained from the IEEE." Article also available from publisher: http://dx.doi.org/10.1109/WiMob.2009.13 Cooperative communication has been recently proposed as a powerful means to improve network performance in wireless networks. However, most existing work focuses solely on one-hop source-destination cooperation. In this paper, we propose a novel cooperative MAC mechanism that is spe…
Optimization of the relay selection scheme in cooperative retransmission networks
2011
Accepted version of a paper in the book: 2011 IEEE 73rd Vehicular Technology Conference (VTC Spring). Published version available from the IEEE:http://dx.doi.org/10.1109/VETECS.2011.5956485 Cooperative MAC protocol design has attracted much attention recently thanks to the development of relaying techniques. In single-relay C-ARQ, the relay selection scheme cannot work efficiently in a dense network, due to high collision probability among different contending relays. In this paper, the throughput performance impairment from the collision is analyzed in a typical network scenario. Thereby, we propose an optimized relay selection scheme aiming at maximizing system throughput by reducing coll…
An automatic cooperative retransmission MAC protocol in wireless local area networks
2009
©2009 IEEE. Personal use of this material is permitted. However, permission to reprint/republish this material for advertising or promotional purposes or for creating new collective works for resale or redistribution to servers or lists, or to reuse any copyrighted component of this work in other works must be obtained from the IEEE. Article also available from publisher: http://dx.doi.org/10.1109/EW.2009.5357992 Existing solutions for cooperation in wireless networks either require simultaneous transmission of source and relay nodes or impose major modifications to original MAC protocols. In this paper, a new efficient retransmission MAC protocol is proposed for IEEE 802.11 based cooperati…
An optimal energy efficient cooperative retransmission MAC scheme in wireless networks
2011
Accepted version of a paper in the book: 2011 2nd Wireless Communication, Vehicular Technology, Information Theory and Aerospace & Electronic Systems Technology (Wireless VITAE). Published version available from the IEEE: http://dx.doi.org/10.1109/WIRELESSVITAE.2011.5940871 While the benefits of cooperative diversity have been well studied in the literature, cooperative MAC protocol design has also attracted much attention recently. In the single-relay Cooperative Automatic Repeat reQuest (C-ARQ) protocol, the best relay node is selected in a distributed manner by relays using different backoff time before packet retransmission. However, this relay selection scheme does not work efficiently…