An Enhanced Medium Access Control Protocol For Ad Hoc Networks

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An Enhanced Medium Access Control Protocol For Ad Hoc Networks

Author : Priyadarshini Sabut
ISBN : 3838393473
Genre :
File Size : 90.43 MB
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Ad hoc Networks are the most popular networks and are useful in many application environments due to less cost and easy deployment at anytime anywhere. The efficiency of these networks depends on the performance and reliability of the medium access control (MAC) protocol applied in such networks. The IEEE 802.11 DCF MAC protocol for ad hoc networks suffers from the problem of bandwidth sharing due to presence of hidden and exposed nodes. This book discusses a MAC protocol that not only overcomes the problem of hidden and exposed nodes but also allows the hidden nodes to transmit and exposed nodes to receive without interfering with the ongoing transmission in their vicinity, thereby improving channel utilization. The proposed protocol outperforms IEEE 802.11 DCF MAC in terms of throughput and packet delivery ratio with a little cost of control overhead.
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Enhanced Synchronized Medium Access Control Protocol For Wireless Ad Hoc Network

Author : Shenbo Liu
ISBN : OCLC:79628061
Genre : Computer networks
File Size : 33.11 MB
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"In this thesis, a new synchronized medium access protocol (MAC), named ES-MAC, for wireless ad hoc networks is proposed. ES-MAC employs a binary-countdown scheme to resolve contentions between wireless systems. There are three coherent phases in the proposed ES-MAC, namely, contention resolution phase, hidden station elimination phase, and data transmission phase. ES-MAC is simple, efficient, fair, and quality of service (QoS) capable. Along with mathematical analysis, a simulator based on GloMoSim is developed. The simulation and analysis results show that ES-MAC can achieve low collision rate and high efficiency at a wide range of traffic load"--Abstract.
Category: Computer networks

Enhanced Ieee 802 11 P Based Mac Protocols For Vehicular Ad Hoc Networks

Author : Yamen Nasrallah
ISBN : OCLC:1119060909
Genre :
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The Intelligent Transportation System (ITS) is a cooperative system that relies on reliable and robust communication schemes among vehicles and between vehicles and their surroundings. The main objective of the ITS is to ensure the safety of vehicle drivers and pedestrians. It provides an efficient and reliable transportation system that enhances traffic management, reduces congestion time, enables smooth traffic re-routing, and avoids economic losses. An essential part of the ITS is the Vehicular Ad hoc Network (VANET). VANET enables the setup of Vehicle-to-Vehicle (V2V) as well as Vehicle-to-Infrastructure (V2I) communication platforms: the two key components in the ITS. The de-facto standard used in wireless V2V and V2I communication applications is the Dedicated Short Range Communication (DSRC). The protocol that defines the specifications for the Medium Access Control (MAC) layer and the physical layer in the DSRC is the IEEE 802.11p protocol. The IEEE 802.11p protocol and its Enhanced Distributed Channel Access (EDCA) mechanism are the main focus of this thesis. Our main objective is to develop new IEEE 802.11p-based protocol for V2V and V2I communication systems, to improve the performance of safety-related applications. These applications are of paramount importance in ITS, because their goal is to decrease the rate of vehicle collisions, and hence reduce the enormous costs associated with them. In fact, large percentage of vehicle collisions can be easily avoided with the exchange of relevant information between vehicles and the Road Side Units (RSUs) installed on the sides of the roads. In this thesis, we propose various enhancements to the IEEE 802.11p protocol to improve its performance by lowering the average end-to-end delay and increasing the average network throughput. We introduce multiple adaptive algorithms to promote the QoS support across all the Access Categories (AC) in IEEE 802.11p. We propose two adaptive backoff algorithms and two algorithms that adaptively change the values of the Arbitrary Inter-Frame Space (AIFS). Then we extend our model to be applied in a large-scale vehicular network. In this context, a multi-layer cluster-based architecture is adopted, and two new distributed time synchronization mechanisms are developed.
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Performance Enhancements In Wireless Multihop Ad Hoc Networks

Author : Ahmad Ali Abdullah
ISBN : OCLC:858858780
Genre :
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Improving the performance of the wireless multihop ad hoc networks faces several challenges. In omni-directional antenna based solutions, the use of the RTS/CTS mechanism does not completely eliminate the hidden-terminal and exposed-terminal problems. Deafness is an additional challenge to the directional antenna based solutions. This dissertation, first develops analytical models for quantifying the throughput and delay in wireless multihop ad hoc networks. The models consider the impact of hidden terminals using the realistic signal to interference and noise ratio model and consider random node distribution. The proposed analysis is applicable to many wireless MAC protocols and applications. The analytical results reveal several important issues. The first issue is quantifying the impact of adjusting the transmission range on the throughput and delay in wireless multihop ad hoc networks. The other issue is the hidden terminal region is closely related to the distance between the transmitter and the receiver. Thus, it is possible to adjust the transmission range to optimize the whole network performance. These results provide important guidelines for network planning and protocol optimization in wireless multihop ad hoc networks. Second, it proposes a new Enhanced Busy-tone Multiple Access (EBTMA) medium access control (MAC) protocol for minimizing the negative impact of both the hidden-terminal and the exposed-terminal problems. The new protocol can also enhance the reliability of packet broadcasts and multicasts which are important for many network control functions such as routing. Different from other busy-tone assisted MAC protocols, the protocol uses a non-interfering busy-tone signal in ashort period of time, in order to notify all hidden terminals without blocking a large number of nodes for a long time. In addition, the proposed EBTMA protocol can co-exist with the existing 802.11 MAC protocol, so it can be incrementally deployed. Third, it investigates how to support the directional antennas in ad hoc multihop networks for achieving higher spatial multiplexing gain and thus higher network throughput. A new MAC protocol called Dual Sensing Directional MAC (DSDMAC) protocol for wireless ad hoc networks with directional antennas is proposed. The proposed protocol differs from the existing protocols by relying on a dual sensingstrategy to identify deafness, resolve the hidden-terminal problem and to avoid unnecessary blocking. Finally, this dissertation provides important results that help for network planning and protocol optimization in wireless multihop ad hoc networks in quantifying the impact of transmission range on the throughput and the delay. The accuracy of these results has been verified with extensive discrete event simulations.
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High Performance Medium Access Control Protocols For Decentralized Wireless Networks Using Local Coordination

Author :
ISBN : 1109249195
Genre : Wireless communication systems
File Size : 41.58 MB
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Wireless networks differ from their wired counterparts in that communication between nodes takes place over a "link" using an RF, acoustic, optical, or other signal transmitted through the air or water instead of, as their name implies, a wire. This difference changes the frequency of transmission errors from extremely rare to almost constant, and introduces inter-node interference as a significant problem. Wireless networks are typically more limited than wired networks in terms of bandwidth, computational ability, power, and centralized management. Efficient handling of transmission errors and reducing interference are thus vital in maximizing network performance. This dissertation addresses two separate aspects of wireless networks with a common theme of low overhead, local coordination between nodes, and often using inferences or even informed guesses to make decisions. To address the problem of transmission errors, we study two medium access control (MAC) protocols that use minimal-overhead, local coordination schemes to allow cooperation between neighboring nodes: one with and one without a cooperation-enabled physical layer. To address the problem of interference, we study two closely related MAC protocols that use local coordination between neighboring nodes to build an interference-free transmission schedule, for (1) supporting latency-sensitive applications over long routes in mesh networks, and (2) increasing channel utilization and energy efficiency in underwater acoustic networks. Our first work focuses on mobile ad hoc networks where if any link in a route fails, multiple fruitless attempts are currently made by most of the existing MAC protocols to use the failed link before reporting failure to the routing layer and/or attempting local recovery. The high frequency of link errors between mobile nodes requires rapid recovery to provide acceptable performance. We design CIFLER, a cross-layer approach which uses enhanced channel reservation messages to allow alternate nodes to immediately elect themselves using only inferred neighbor information. This self-election avoids reliance on individual links, and uses diversity to minimize the impact frequent link errors have on delay, energy efficiency, and the functioning of upper layer protocols. We show via both analysis and simulation that CIFLER provides better performance in typical MANET scenarios. Unlike other local recovery schemes, CIFLER uses only a minor modification to IEEE 802.11 DCF, does not suffer from duplicated messages, allows neighboring nodes to almost immediately learn the information needed to assist in the recovery of existing routes, and does not require additional hardware, delays, or control messages. Our second work applies the same concept of inferred neighbor information to cooperative communications, where the signals of simultaneous transmissions by multiple nodes constructively combine in the wireless medium. Studies on the physical layer capabilities (via either information theory or numerical analysis) have shown the significant performance improvements of cooperative communications. However, these studies ignore both the overheads incurred in real implementations of the cooperative techniques at the physical layer and their interactions with higher layer protocols in a networking context. We implement a path-centric MAC protocol that uses minimal control messages to reserve a multi-hop path between source and destination nodes, and perform coordination between relay nodes. We then realistically study the performance of cooperation in networking scenarios by taking into account overheads incurred at the physical, MAC, and network layers. Simulations demonstrate that significant performance improvement can be achieved by employing cooperation. We also demonstrate the overheads which challenge the effectiveness of such schemes in real networks. Our third work deals with the issue of interference and transmission scheduling in mesh networks, where links are generally reliable if no interference is present. In current wireless networks, access to the shared wireless medium is controlled via either a TDMA- or a CSMA-based scheme. While usable in single-hop networks, these techniques are often far from optimal, and result in significant per-hop and per-packet delay and jitter, making multi-hop wireless mesh networks a particularly harsh environment for real-time, isochronous applications such as VoIP. We present a new time-based MAC protocol, FLASHR, for wireless mesh networks carrying delay-sensitive isochronous traffic. In our scheme, nodes use simple local coordination mechanisms to form adaptive transmission schedules which attain the desired quality of service. Simulations show that our scheme achieves near-optimal capacity, minimal jitter, and a weaker correlation between route length and end-to-end delay. Our final work adapts the FLASHR MAC protocol for use in underwater acoustic networks. A time-based MAC has potential advantages over FDMA and CDMA approaches in terms of hardware simplicity, energy efficiency, and delay. Unfortunately, the channel utilization of existing TDMA and CSMA acoustic MAC protocols is generally low due to the long propagation delays of acoustic signals. We argue that several ideas taken from RF protocols, including exclusive channel access, are either unnecessary in acoustic networks or must be redefined. We design UW-FLASHR, a modification to FLASHR which uses additional local control messages to create a time-based MAC protocol for acoustic networks which does not require centralized control, tight clock synchronization, or accurate propagation delay estimation. Our results show that UWFLASHR achieves higher channel utilization than the maximum utilization possible with existing time-based exclusive-access MAC protocols, particularly when the ratio of propagation delay to transmission delay is high, or data payloads are small.
Category: Wireless communication systems

Wireless Network Performance Enhancement Via Directional Antennas Models Protocols And Systems

Author : John D. Matyjas
ISBN : 9781498707541
Genre : Technology & Engineering
File Size : 75.3 MB
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Directional antenna technologies have made significant advancements in the last decade. These advances have opened the door to many exciting new design opportunities for wireless networks to enhance quality of service (QoS), performance, and network capacity. In this book, experts from around the world present the latest research and development in wireless networks with directional antennas. Their contributed chapters provide detailed coverage of the models, algorithms, protocols, and applications of wireless networks with various types of directional antennas operating at different frequency bands. Wireless Network Performance Enhancement via Directional Antennas: Models, Protocols, and Systems identifies several interesting research problems in this important field, providing an opportunity to learn about solid solutions to these issues. It also looks at a number of practical hardware designs for the deployment of next-generation antennas, as well as efficient network protocols for exploitation of directional communications. The book is organized into six sections: Directional Antennas – covers the hardware design of different types of antennas Directional MAC – focuses on the principles of designing medium access control (MAC) protocols for directional networks Millimeter Wave – explores different design aspects of millimeter wave (mm-Wave) systems, which operate in higher-frequency bands (such as 60 GHz) MIMO – explains how to establish a multiple-input, multiple-output (MIMO) antenna system and describes how it operates in a cognitive radio network Advanced Topics – looks at additional topics such as beamforming in cognitive radio networks, multicast algorithm development, network topology management for connectivity, and sensor network lifetime issues Applications – illustrates some important applications, such as military networks and airborne networking, that benefit from directional networking designs With this book, researchers and engineers will be well-equipped to advance the research and development in this important field. If you’re new to this field, you will find this book to be a valuable reference on basic directional networking principles, engineering design, and challenges.
Category: Technology & Engineering

Quality Of Service Based Medium Access Control Mechanism For Multimedia Traffic In Mobile Ad Hoc Networks

Author : Mubarak Abdallah Jama
ISBN : OCLC:975192276
Genre :
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This thesis describes an investigation on the problem of quality of service (QoS) support in mobile ad hoc networks (MANETs). The decentralized nature of wireless ad hoc networks makes them suitable for a variety of applications where central nodes cannot be relied on. This thesis presents a medium access control (MAC) QoS mechanism for multimedia applications in IEEE 802.11e based MANETs. IEEE 802.11e standard draft includes new features to facilitate and promote the provision of QoS guarantees in wireless networks with a long-term solution based on QoS-architectures. The motivation is driven by the need to support increasing demand of time-sensitive applications such as Voice over IP (VoIP) and video conferencing applications. IEEE 802.11e enhances the Distributed Coordination Function (DCF) and the Point Coordination Function (PCF) of the legacy IEEE 802.11, through a new coordination function: the Hybrid Coordination Function (HCF). Within the HCF, there are two methods of channel access: HCF Controlled Channel Access (HCCA) and Enhanced Distributed Channel Access (EDCA). EDCA operates in infrastructure-less ad hoc mode and is widely used in MANETs, unlike HCCA, which further assures QoS provisioning operates in infrastructure mode in the presence of access points (AP). Recent researches showed that EDCA lacks QoS support of real-time traffic in MANETs due to its contention based medium access method. This thesis takes HCCA QoS provisioning potentials to MANETs by implementing a MAC mechanism in which HCCA is employed on top of EDCA to work in infrastructure-less environment like MANET with the help of multiple channels. The mechanism dedicates a unique receiver-based channel to every mobile node. It will act as virtual hybrid coordinator (VHC) to exercise control over the channel in contention-free manner while maintaining a common channel in which all mobile nodes can exchange broadcast and routing related messages. The mechanism can be easily integrated with existing 802.11 systems without modification to existing protocols while ensuring a level of admission control and resource reservation over the medium. Simulation results indicate that the mechanism significantly improves the overall network throughput by 20% at the saturation point and improves average delay by 20% at the saturation point compared to pure EDCA with or without multiple channels. Even with multi-channel EDCA, our mechanism guarantees better performance in terms of throughput and MAC delay for high priority traffic in MANET. The research contribution on MAC layer can be integrated into a larger framework for QoS support in MANETs, which opens a wide range of further research in QoS provisioning in MANETs and solve QoS multi-layer design and implementation issues.
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Spatial Reuse And Collision Avoidance In Ad Hoc Networks With Directional Antennas

Author :
ISBN : OCLC:227911285
Genre :
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The quest for efficient medium access control (MAC) protocols for multi-hop ad hoc networks has aroused great interest in using directional antennas. Some MAC protocols using directional antennas have been proposed in the past, which trade off spatial reuse and collision avoidance via a combination of omni-directional and directional transmission modes. In this paper, the authors argue that the benefit of spatial reuse achieved by a MAC protocol that uses directional mode in all transmissions can outweigh the benefit of a conservative collision avoidance MAC protocol that sends some omni-directional control packets to silence potential interfering nodes. Detailed simulation experiments of the popular IEEE 802.11 MAC protocol and its variants that make use of directional transmission mode in sufficiently random networks are presented. It is concluded that, in contention-based MAC protocols for multi-hop networks infested with hidden terminals, the aggressive channel access scheme featured by all-directional transmissions indeed outperforms other conservative schemes in terms of enhanced throughput and reduced delay.
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Adaptation And Cross Layer Design In Wireless Networks

Author : Mohamed Ibnkahla
ISBN : 9781420046106
Genre : Technology & Engineering
File Size : 56.62 MB
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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.
Category: Technology & Engineering

Adaptation In Wireless Communications 2 Volume Set

Author : Mohamed Ibnkahla
ISBN : 9781482290332
Genre : Technology & Engineering
File Size : 80.74 MB
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The widespread use of adaptation techniques has helped to meet the increased demand for new applications. From adaptive signal processing to cross layer design, Adaptation in Wireless Communications covers all aspects of adaptation in wireless communications in a two-volume set. Each volume provides a unified framework for understanding adaptation and relates various specializations through common terminologies. In addition to simplified state-of-the-art cross layer design approaches, they also describe advanced techniques, such as adaptive resource management, 4G communications, and energy and mobility aware MAC protocols.
Category: Technology & Engineering

Microelectronics

Author : Jerry C. Whitaker
ISBN : 9781351836371
Genre : Technology & Engineering
File Size : 38.70 MB
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When it comes to electronics, demand grows as technology shrinks. From consumer and industrial markets to military and aerospace applications, the call is for more functionality in smaller and smaller devices. Culled from the second edition of the best-selling Electronics Handbook, Microelectronics, Second Edition presents a summary of the current state of microelectronics and its innovative directions. This book focuses on the materials, devices, and applications of microelectronics technology. It details the IC design process and VLSI circuits, including gate arrays, programmable logic devices and arrays, parasitic capacitance, and transmission line delays. Coverage ranges from thermal properties and semiconductor materials to MOSFETs, digital logic families, memory devices, microprocessors, digital-to-analog and analog-to-digital converters, digital filters, and multichip module technology. Expert contributors discuss applications in machine vision, ad hoc networks, printing technologies, and data and optical storage systems. The book also includes defining terms, references, and suggestions for further reading. This edition features two new sections on fundamental properties and semiconductor devices. With updated material and references in every chapter, Microelectronics, Second Edition is an essential reference for work with microelectronics, electronics, circuits, systems, semiconductors, logic design, and microprocessors.
Category: Technology & Engineering

Medium Access Control In Wireless Networks

Author : Hongyi Wu
ISBN : 1600219446
Genre : Technology & Engineering
File Size : 58.2 MB
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Wireless technologies and applications are becoming one of the fastest growing and most promising areas in recent years. To accommodate data transmission by multiple stations sharing the scarce wireless bandwidth, a medium access control (MAC) protocol plays a crucial role in scheduling packet transmission fairly and efficiently. The emerging wireless networks, such as ad-hoc networks, sensor networks or mesh networks, are mostly multi-hop based and in distributed manner, which brings a lot of problems and challenges in designing fine-tuned MAC protocols tailored for modern wireless network. In this book, the authors give complete and in-depth overviews to the classic medium access control algorithms and the related protocols, as well as their applications in various wireless data networks especially the most successful Wireless Local Area Networks (WLAN). The book consists of three major parts. Part I of this book, including Chapters 1-7, is emphasising on the fundamentals of medium access control algorithms and protocols. Chapter 1 provides an introduction to the wireless networks, such as overview of wireless networks, problems and challenges of the wireless networks, and the classifications of MAC protocols as well as the performance metrics. Chapter 2 introduces important collision resolution algorithms applied in medium access controls, for example, the splitting algorithm and the backoff algorithm. Chapter 3 reviews the hybrid access control algorithms that combine both contention and allocation schemes. A series of important collision avoidance schemes are introduced in Chapters 4-7 respectively, with a specific design goal covered in each chapter. Chapter 4 focuses on the multi-channel MAC protocols for collision avoidance; Chapter 5 introduces the concepts of power control and power management in medium access control and how they can be applied in MAC protocol design; Chapter 6 presents how to provide Quality-of- Service (QoS) to multimedia wireless networks, in either centralised or distributed manner; and Chapter 7 explains how the smart antennas can be applied in the medium access control to provide high channel throughput and low packet collision.
Category: Technology & Engineering

Multi Hop Ad Hoc Networks From Theory To Reality

Author : Marco Conti
ISBN : 1600216056
Genre : Computers
File Size : 35.86 MB
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Mobile Multi-hop Ad Hoc Networks are collections of mobile nodes connected together over a wireless medium. These nodes can freely and dynamically self-organise into arbitrary and temporary, "ad-hoc" network topologies, allowing people and devices to seamlessly internetwork in areas with no pre-existing communication infrastructure, (e.g., disaster recovery environments). The aim of this book is to present some of the most relevant results achieved by applying an experimental approach to the research on multi-hop ad hoc networks. The unique aspect of the book is to present measurements, experiences and lessons obtained by implementing ad hoc networks prototypes.
Category: Computers

Mimo Aware Medium Access Control In Ieee 802 11 Networks

Author : Abduladhim Mabruk Ashtaiwi
ISBN : OCLC:672300313
Genre :
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Wireless Mesh Networks (WMNs) are dynamically self-organized and self-configured, where the nodes in the network automatically establish an ad hoc network and maintain mesh connectivity. These properties make WMNs a key technology for next generation wireless networking. However, supporting Quality of Service (QoS) to enable multimedia services is still one of the major issues in next-generation WMNs. In distributed systems like WMNs, the Medium Access Control (MAC) layer is considered very important in the IEEE 802.11-based wireless networks, as it supports many crucial operational functions. Hence, QoS support in WMNs can be enhanced through the efficient cross-layer design of MAC protocols that utilizes advanced physical layer technologies viz Multiple-Input Multiple-Output (MIMO) with its multiple spatial channels that are capable of simultaneous receive or transmit streams. MIMO has become a very attractive technology in providing support for different QoS requirements. In this thesis we propose a novel QoS MIMO-aware MAC Protocol (QMMP). QMMP is a MAC protocol framework that exploits the MIMO system gains to boost QoS support. The proposed MAC framework includes the following components. The first component enables concurrent sharing of the increased MIMO bandwidth, i.e., instead of allocating all the spatial channels to one connection, connections can concurrently share the increase bandwidth via splitting the spatial channels. The second component reduces the medium access collisions problem. In distributed systems like WMNs, medium access collisions have a noticeably negative impact on resource (bandwidth) utilization as they leave the bandwidth unutilized for a long time. To address this problem, we propose a spatial channels sharing scheme during medium contention period. The third component boosts the bandwidth utilization during data transmission. We propose resource management schemes that adapt the physical data rate and the aggregation frame length according to the instantaneous channel quality. Then we propose a QoS-aware bandwidth provisioning mechanism that performs effective bandwidth distribution to further boost QoS support.
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Distributed Medium Access Control In Wireless Networks

Author : Ping Wang
ISBN : 9781461466024
Genre : Computers
File Size : 71.3 MB
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This brief investigates distributed medium access control (MAC) with QoS provisioning for both single- and multi-hop wireless networks including wireless local area networks (WLANs), wireless ad hoc networks, and wireless mesh networks. For WLANs, an efficient MAC scheme and a call admission control algorithm are presented to provide guaranteed QoS for voice traffic and, at the same time, increase the voice capacity significantly compared with the current WLAN standard. In addition, a novel token-based scheduling scheme is proposed to provide great flexibility and facility to the network service provider for service class management. Also proposed is a novel busy-tone based distributed MAC scheme for wireless ad hoc networks and a collision-free MAC scheme for wireless mesh networks, respectively, taking the different network characteristics into consideration. The proposed schemes enhance the QoS provisioning capability to real-time traffic and, at the same time, significantly improve the system throughput and fairness performance for data traffic, as compared with the most popular IEEE 802.11 MAC scheme.
Category: Computers

Telecommunications And Networking Ict 2004

Author : José Neuman De Souza
ISBN : 9783540278245
Genre : Technology & Engineering
File Size : 45.57 MB
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Welcometothe11thInternationalConferenceonTelecommunications(ICT2004)ho- ed by the city of Fortaleza (Brazil). As with other ICT events in the past, this professional meeting continues to be highly competitive and very well perceived by the international networking community, - tracting excellent contributions and active participation. This year, a total of 430 papers from 36 countries were submitted, from which 188 were accepted. Each paper was - viewed by several members of the ICT2004 Technical Program Committee. We were very pleased to receive a large percentage of top-quality contributions. Thetopicsofsubmittedpaperscoveredawidespectrumfromphotonictechniques,signal processing,cellularnetworks,andwirelessnetworks,toadhocnetworks.Webelievethe ICT2004papersofferawiderangeofsolutionstokeyproblemsintelecommunications, and describe challenging avenues for industrial research and development. In addition to the conference regular sessions, seven tutorials and a workshop were organized.Thetutorialsfocusedonspecialtopicsdealingwithnext-generationnetworks. The workshop focused on particular problems and solutions in heavily distributed and shareable environments. We would like to thank the ICT 2004 Technical Program Committee members and referees. Without their support, the creation of such a broad conference program would not be possible. We also thank all the authors who made a particular effort to contribute to ICT2004. We truly believe that due to all these efforts the ?nal conference program consisted of top-quality contributions. We are also indebted to many individuals and organizations that made this conference possible. In particular, we would like to thank the members of the ICT2004 Organizing Committee for their help in all aspects of the organization of this professional meeting.
Category: Technology & Engineering

The Electronics Handbook

Author : Jerry C. Whitaker
ISBN : 9781420036664
Genre : Technology & Engineering
File Size : 22.18 MB
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During the ten years since the appearance of the groundbreaking, bestselling first edition of The Electronics Handbook, the field has grown and changed tremendously. With a focus on fundamental theory and practical applications, the first edition guided novice and veteran engineers along the cutting edge in the design, production, installation, operation, and maintenance of electronic devices and systems. Completely updated and expanded to reflect recent advances, this second edition continues the tradition. The Electronics Handbook, Second Edition provides a comprehensive reference to the key concepts, models, and equations necessary to analyze, design, and predict the behavior of complex electrical devices, circuits, instruments, and systems. With 23 sections that encompass the entire electronics field, from classical devices and circuits to emerging technologies and applications, The Electronics Handbook, Second Edition not only covers the engineering aspects, but also includes sections on reliability, safety, and engineering management. The book features an individual table of contents at the beginning of each chapter, which enables engineers from industry, government, and academia to navigate easily to the vital information they need. This is truly the most comprehensive, easy-to-use reference on electronics available.
Category: Technology & Engineering

Computational Science Iccs 2007

Author : Yong Shi
ISBN : 9783540725893
Genre : Computers
File Size : 64.15 MB
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Part of a four-volume set, this book constitutes the refereed proceedings of the 7th International Conference on Computational Science, ICCS 2007, held in Beijing, China in May 2007. The papers cover a large volume of topics in computational science and related areas, from multiscale physics to wireless networks, and from graph theory to tools for program development.
Category: Computers

Protocol Design And Analysis For Cooperative Wireless Networks

Author : Wei Song
ISBN : 9783319477268
Genre : Technology & Engineering
File Size : 43.2 MB
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This book focuses on the design and analysis of protocols for cooperative wireless networks, especially at the medium access control (MAC) layer and for crosslayer design between the MAC layer and the physical layer. It highlights two main points that are often neglected in other books: energy-efficiency and spatial random distribution of wireless devices. Effective methods in stochastic geometry for the design and analysis of wireless networks are also explored. After providing a comprehensive review of existing studies in the literature, the authors point out the challenges that are worth further investigation. Then, they introduce several novel solutions for cooperative wireless network protocols that reduce energy consumption and address spatial random distribution of wireless nodes. For each solution, the book offers a clear system model and problem formulation, details of the proposed cooperative schemes, comprehensive performance analysis, and extensive numerical and simulation results that validate the analysis and examine the performance under various conditions. The last section of this book reveals several potential directions for the research on cooperative wireless networks that deserve future exploration. Researchers, professionals, engineers, and consultants in wireless communication and mobile networks will find this book valuable. It is also helpful for technical staff in mobile network operations, wireless equipment manufacturers, wireless communication standardization bodies, and governmental regulation agencies.
Category: Technology & Engineering

Wireless And Satellite Systems

Author : Qihui Wu
ISBN : 9783030690724
Genre : Computers
File Size : 88.46 MB
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This two-volume set LNICST 357-358 constitutes the post-conference proceedings of the 11th EAI International Conference on Wireless and Satellite Services, WiSATS 2020, held in Nanjing, China, in September 2020. The 91 full papers and workshop papers were carefully reviewed and selected from 200 submissions. Part I - LNICST 357 - details original research and results of wireless and satellite technology for a smarter global communication architecture. The theme of WISATS 2020 is “Intelligent Wireless and Satellite Communications for Beyond 5G”. Part II – LNICST 358 - presents 6 workshop papers: High Speed Space Communication and Space Information Networks (HSSCSIN); Integrated Space and Onboard Networks (ISON); Intelligent Satellite Operations, Managements, and Applications (ISOMA); Intelligent Satellites in Future Space Networked System (ISFSNS); Satellite Communications, Networking and Applications (SCNA); Satellite Internet of Things; Trusted Data Sharing, Secure Communication (SIOTTDSSC).
Category: Computers