Download or read book Cross layer Optimization in Wireless Local Area Networks written by and published by . This book was released on 2004 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis studies several research problems in the area of wireless local area networks (WLANs) with an objective of improving network efficiency, quality-of-service and user satisfactions. The I E E E 802.11 Working Group has been under rapid development and expansion in recent years following the successful deployment of the 802.11 network around the globe. The thesis work has been striving to study several key problems in these developments and propose effective schemes to improve network performance. The original 802.11 standard presents a simple and robust design, but has relatively low data rate and lacks QoS support. The recent 802.11e standard and the 8 0 2 . l ln proposals aim to significantly improve the network performance in terms of QoS and throughput. In this thesis, an analytical model of I E E E 802.11e WLANs is first presented. With the help of this throughput model, an admission control scheme for a multi-hop 802.11e W L A N is proposed. To fully utilize the high data rate provided by 802.11n, the performance improvement of the M A C protocol by frame aggregation is studied. Two frame aggregation techniques, namely A - M P D U (MAC Protocol Data Unit Aggregation) and A - M S D U (MAC Service Data Unit Aggregation) are considered. Furthermore, a comprehensive network setup is studied where the QoS requirements of the 802.11e M A C and the MIMO physical layer of 8 0 2 . l ln are both considered. Cross-layer design schemes are proposed for WLANs under two different M A C protocols: the carrier sense multiple access with collision avoidance (CSMA/CA)-based 802.11e M A C, and the slotted Aloha M A C . Lastly, the thesis studies the problem of cooperative transmission in a wireless ad-hoc network with extensions to the 802.11 M A C protocols. A complete system framework is proposed for wireless adhoc networks utilizing two different cooperative relaying techniques at the physical layer: the repetition coding and the space-time coding. In the data link.

Download or read book Cross layer Analysis Optimization and Design for Wireless Local Area Networks WLANs written by Xuefu Zhou and published by . This book was released on 2006 with total page 132 pages. Available in PDF, EPUB and Kindle. Book excerpt: An underlying assumption of the traditional layered protocol architecture is that all layers can be optimized independently. Unfortunately, this assumption is not satisfied in wireless networks because wireless links introduce interdependence between PHY and upper layers. This dissertation investigates the impact of channel conditions on the performance of IEEE 802.11 DCF and proposes cross-layer optimization and design approach to improve the performance of DCF in fade channels. First, novel fade-induced packet error rate expressions based on fading statistics and error correction capability are developed. Based on these results, we propose a cross-layer analytical model to analyze the performance of IEEE 802.11 DCF in fading channels. The impact of channel conditions on the DCF performance is revealed. Second, a viable cross-layer optimization and design approach to improve the performance of DCF in fading channels is proposed. By employing the practically measurable PHY information, the DCF can adapt its packet length to maximize the throughput. By deploying multiple antennas at PHY for the purpose of spatial diversity, fading-induced packet error rate is reduced and the DCF performance in fading channels is significantly improved. Ironically, in wireless networks, channel fading and path loss may degrade the signal quality at the receiver and cause fade-induced packet errors; however, they also result in capture effect phenomena to make it possible for some packets to be received successfully in the presence of collision. Well-known capture probability expressions exist for Rayleigh fading channels, i.e., non-line-of-sight environments. However, WLANs using DCF are supposed to be deployed in micro-cellular and pico-cellular environments where Ricean fading channels are more likely to exist. Therefore, we develop a new analytical expression for the capture probability for WLANs using DCF in Ricean fading channels. Furthermore, by incorporating the capture probability expression, we evaluate the DCF performance in fading channels with capture effect. Results show that, with capture effect, the performance of DCF in fading channels is better than that under ideal channel conditions without capture effect.

Download or read book Cross Layer Optimization Techniques for Wireless Networks written by Shahbaz Khan and published by LAP Lambert Academic Publishing. This book was released on 2011-08 with total page 192 pages. Available in PDF, EPUB and Kindle. Book excerpt: The tremendous growth of Information and Communication Technology (ICT) has unknowingly influenced our lifestyle. We are making more phone calls, exchanging more emails and spending more time on the World Wide Web than we did a decade ago. The nature of information content is also evolving. High definition video streaming, online shopping, online banking and content sharing libraries are some of the new paradigms that have replaced the simple web applications of early days. In such circumstances, the objectives for future networks are more challenging. This book focuses on the IEEE 802.11 MAC and identifies several challenges that require further research. The IEEE 802.11 standard for local area networks, specifically the IEEE 802.11e, is discussed in a tutorial style. The primary focus is on rate-adaptation schemes for multi-rate WLANs stations and design of QoS enabled routing protocol by incorporating information from the IEEE 802.11e compliant MAC. The book serves as a valuable reference for researchers, professionals and students who would like to gain a more formal understanding of Cross-layer optimization techniques and specifically the IEEE 802.11 standard.

Download or read book Wireless Networks Multiuser Detection in Cross Layer Design written by Christina Comaniciu and published by Springer Science & Business Media. This book was released on 2006-06-14 with total page 214 pages. Available in PDF, EPUB and Kindle. Book excerpt: Cross-layer design seeks to enhance the capacity of wireless networks significantly through the joint optimization of multiple layers in the network, primarily the physical (PHY) and medium access control (MAC) layers. Although there are advantages of such design in wireline networks as well, this approach is particularly advantageous for wireless networks due to the properties (such as mobility and interference) that strongly affect performance and design of higher layer protocols. This unique monograph is concerned with the issue of cross-layer design in wireless networks, and more particularly with the impact of node-level multiuser detection on such design. It provides an introduction to this vibrant and active research area insufficiently covered in existing literature, presenting some of the principal methods developed and results obtained to date. Accompanied by numerous illustrations, the text is an excellent reference for engineers, researchers and students working in communication networks.

Download or read book Cross Layer Optimization of Complex Wireless Environments written by Stephen B. Gwanvoma and published by . This book was released on 2014 with total page 142 pages. Available in PDF, EPUB and Kindle. Book excerpt: Cross-layer design and optimization is a new technique which can be used to design and improve the performance in both wireless and wireline networks. The central idea of cross-layer design is to optimize the control and exchange of information over two or more layers to achieve significant performance improvements by exploiting the interaction between various protocol layers. Designing for wireless networks such as cellular networks, WLANs, mobile ad hoc networks (MANETs) and Wireless Sensor Networks (WSNs), poses more stringent requirements than wireline networks and are considerably different in their applications and architectures, although all use wireless channel for communication. Promising results achieved by cross-layer optimizations initiated significant research activity in this area. Due to features such as ease of deployment, increased coverage and enhanced capacity, multi hop wireless networks like ad hoc networks, and mixed network that form the network in a self-organized manner without relying on fixed infrastructure is touted as the new frontier of wireless networking. This work aims to review the present study on the cross-layer paradigm for QoS support in multi-hop wireless networks. Several examples of evolutionary and revolutionary cross-layer approaches are presented in detail. The Cross-Talk architecture represents one of the more aggressive approaches to cross layer improvement. This architecture enables performance related decisions at the global level that can propagate down to the local layer. This architecture fits the Mixed Network modeling developed here at MSU for the iNET project. Organizing the Mixed Networks solutions into the framework of the Cross-Talk Architecture will allow this work to build on the body of research already in place for cross layering.-- Abstract.

Download or read book Cross Layer Optimization for Protocols in Mobile Adhoc Networks written by Anita Yadav and published by GRIN Verlag. This book was released on 2020-03-17 with total page 142 pages. Available in PDF, EPUB and Kindle. Book excerpt: Doctoral Thesis / Dissertation from the year 2016 in the subject Computer Science - Miscellaneous, grade: 16, , language: English, abstract: In this thesis, we have modified AODV routing protocol by incorporating link prediction algorithm using a proposed link prediction model. This algorithm predicts the link availability time and even before the link breaks; either it repairs the route locally or sends information to the source nodes to enable them to initiate a new route search well in time. This algorithm improves the quality of service of the network. Simulation results show that AODV routing algorithm with link availability model performs better than the existing AODV. Advances in wireless technology and hand-held computing devices have brought revolution in the area of mobile communication. The increasing mobility of humans across the globe generated demand for infrastructure-less and quickly deployable mobile networks. Such networks are referred to as Mobile Adhoc Networks (MANET). Usually, nodes in a MANET also act as a router while being is free to roam while communicating each others. Adhoc networks are suited for use in situations where infrastructure is unavailable or to deploy one is not cost-effective. Frequent changes in network topology due to mobility and limited battery power of the mobile devices are the key challenges in the adhoc networks. The depletion of power source may cause early unavailability of nodes and thus links in the network. The mobility of nodes will also causes frequent routes breaks and adversely affects the required performance for the applications. Availability of a route in future mainly depends on the availability of links between the nodes forming the route. Therefore, it is important to predict the future availability of a link that is currently available. We have proposed an analytical model for link prediction using Newton divided difference method. This link availability algorithm is incorporated in AODV routing algorithm (AODVLP) to evaluate the performance of AODV routing protocol using the metrics viz. delivery rate, average end-to-end delay, average RTS collisions per node and route failure. In the existing AODV protocol, packets are routed until a link in the existing path fails. This results in degradation of quality of service of network in terms of end-to-end delay and delivery ratio.

Download or read book Using Cross Layer Techniques for Communication Systems written by Rashvand, Habib F. and published by IGI Global. This book was released on 2012-04-30 with total page 656 pages. Available in PDF, EPUB and Kindle. Book excerpt: Although the existing layering infrastructure--used globally for designing computers, data networks, and intelligent distributed systems and which connects various local and global communication services--is conceptually correct and pedagogically elegant, it is now well over 30 years old has started create a serious bottleneck. Using Cross-Layer Techniques for Communication Systems: Techniques and Applications explores how cross-layer methods provide ways to escape from the current communications model and overcome the challenges imposed by restrictive boundaries between layers. Written exclusively by well-established researchers, experts, and professional engineers, the book will present basic concepts, address different approaches for solving the cross-layer problem, investigate recent developments in cross-layer problems and solutions, and present the latest applications of the cross-layer in a variety of systems and networks.

Download or read book Decomposition Methods for Cross layer Optimization in Wireless Networks written by Daniel Ernesto Barreto and published by . This book was released on 2008 with total page 236 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Cross Layer Design and Optimization of Wireless Networks written by Hujun Yin and published by . This book was released on 2001 with total page 272 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Resource Allocation and Cross layer Control in Wireless Networks written by Leonidas Georgiadis and published by Now Publishers Inc. This book was released on 2006 with total page 161 pages. Available in PDF, EPUB and Kindle. Book excerpt: Information flow in a telecommunication network is accomplished through the interaction of mechanisms at various design layers with the end goal of supporting the information exchange needs of the applications. In wireless networks in particular, the different layers interact in a nontrivial manner in order to support information transfer. In this text we will present abstract models that capture the cross-layer interaction from the physical to transport layer in wireless network architectures including cellular, ad-hoc and sensor networks as well as hybrid wireless-wireline. The model allows for arbitrary network topologies as well as traffic forwarding modes, including datagrams and virtual circuits. Furthermore the time varying nature of a wireless network, due either to fading channels or to changing connectivity due to mobility, is adequately captured in our model to allow for state dependent network control policies. Quantitative performance measures that capture the quality of service requirements in these systems depending on the supported applications are discussed, including throughput maximization, energy consumption minimization, rate utility function maximization as well as general performance functionals. Cross-layer control algorithms with optimal or suboptimal performance with respect to the above measures are presented and analyzed. A detailed exposition of the related analysis and design techniques is provided.

Download or read book Cross layer Optimization of Wireless Networks written by Wei Feng and published by . This book was released on 2011 with total page 184 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Cross Layer Optimization in 4G Wireless Mesh Networks written by Imam Mahmud Taifur Rahman AL-Wazedi and published by . This book was released on 2010 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Cross layer Optimization and Cooperative Communications in Wireless Networks written by and published by . This book was released on 2006 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Cross-layer optimization and cooperative communications in wireless networks.

Download or read book Adaptation and Cross Layer Design in Wireless Networks written by Mohamed Ibnkahla and published by CRC Press. This book was released on 2018-10-08 with total page 526 pages. Available in PDF, EPUB and Kindle. Book excerpt: Adaptive techniques play a key role in modern wireless communication systems. The concept of adaptation is emphasized in the Adaptation in Wireless Communications Series through a unified framework across all layers of the wireless protocol stack ranging from the physical layer to the application layer, and from cellular systems to next-generation wireless networks. Adaptation and Cross Layer Design in Wireless Networks is devoted to adaptation in the data link layer, network layer, and application layer. The book presents state-of-the-art adaptation techniques and methodologies, including cross-layer adaptation, joint signal processing, coding and networking, selfishness in mobile ad hoc networks, cooperative and opportunistic protocols, adaptation techniques for multimedia support, self –organizing routing, and tunable security services. It presents several new theoretical paradigms and analytical findings which are supported with various simulation and experimental results. Adaptation in wireless communications is needed in order to achieve high capacity and ubiquitous communications. The current trend in wireless communication systems is to make adaptation dependent upon the state of the relevant parameters in all layers of the system. Focusing on simplified cross layer design approaches, this volume describes advanced techniques such as adaptive resource management, adaptive modulation and coding, 4G communications, QoS, diversity combining, and energy and mobility aware MAC protocols. The first volume in the series, Adaptive Signal Processing in Wireless Communications (cat no.46012) covers adaptive signal processing at the physical layer.

Download or read book Cross layer Optimization Protocols in Ad hoc Wireless Networks written by Marco Belleschi and published by . This book was released on 2007 with total page 120 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Cross layer Throughput Optimization of Wireless Networks written by Eyidayo Friday Adebola and published by . This book was released on 2012 with total page 142 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Cross Layer Optimization for Next Generation Wireless Networks written by Mauro De Sanctis and published by . This book was released on 2006 with total page 146 pages. Available in PDF, EPUB and Kindle. Book excerpt: