Download or read book Design and Performance Evaluation of a Radio Resource Management in OFDMA Networks written by Javad Zolfaghari Bengar and published by . This book was released on 2013 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: [ANGLÈS] Inter-cell interference is of great interest and one of the essential issues for wireless operators who want to provide full coverage within their service area and guarantee a certain Quality of Service (QoS) to all users. In this thesis the resource allocation problem in an OFDMA based multi-cell network is formulated. Since no algorithm with polynomial running time exists due to non-linearity and combinatorial nature of underlying problem we adopted a heuristic approach with low computational cost and acceptable performance loss. We address specifically sharing available radio resources among users in terms of bandwidth allocation in order to suppress inter-cell interference. Besides, cell assignment and power allocation is foreseen. Performance of proposed schemes were evaluated by simulation network properly aligned with 3GPP LTE network.

Download or read book Radio Resource Management in Cellular Systems written by Nishith D. Tripathi and published by Springer Science & Business Media. This book was released on 2006-04-18 with total page 244 pages. Available in PDF, EPUB and Kindle. Book excerpt: Radio Resource Management in Cellular Systems is the first book to address the critical issue of radio resource management in emerging (i.e., third generation and beyond) wireless systems. This book presents novel approaches for the design of high performance handoff algorithms that exploit attractive features of several existing algorithms, provide adaptation to dynamic cellular environment, and allow systematic tradeoffs among different system characteristics. Efficient handoff algorithms cost-effectively enhance the capacity and quality of service (QoS) of cellular systems. A comprehensive foundation of handoff and related issues of cellular communications is given. Tutorial-type material on the general features of 3G and 3.5G wireless systems (including CDMA2000, UMTS, and 1xEV-DO) is provided. Key elements for the development of simulators to study handoff and overall RF performance of the integrated voice and data cellular systems (including those based on CDMA) are also described. Finally, the powerful design tools of neural networks and fuzzy logic are applied to wireless communications, so that the generic algorithm approaches proposed in the book can be applied to many other design and development areas. The simulation models described in the book represent a single source that provides information for the performance evaluation of systems from handoff and resource management perspectives. Radio Resource Management in Cellular Systems will prove a valuable resource for system designers and practicing engineers working on design and development of third generation (and beyond) wireless systems. It may also be used as a text for advanced-level courses in wireless communications and neural networks.

Download or read book System Level Performance Evaluation of Radio Resource Allocation Strategies for Long Term Evolution Networks written by Yaser Wajih A. Barayan and published by . This book was released on 2014 with total page 242 pages. Available in PDF, EPUB and Kindle. Book excerpt: This dissertation addresses the performance evaluation of radio resource management (RRM) for 3GPP LTE OFDMA Cellular data networks. The radio resource allocation strategies address processes in which the available scarce and prohibitively expensive radio resources are assigned to each active user. An efficient scheduling algorithm plays an important role for effective utilization of radio resources, high spectrum efficiency, low latency, and fairness among users whithin a system as well as for the entire system performance. The reseach work presented in this dissertation focuses on the performance evaluation of the common packet scheduling algorithms, namely Maximum Rate (MR), Round Robin (RR), and Proportional Fair (PF). Only the scheduling for the downlink (DL) transmission of the LTE cellular systems is considered. The performance evaluation is performed for a regular hexagonal multi cell deployment, universal frequency reuse scheme, Single Input Single Outpt(SISO) versus spatial multiplexing (SM) Multiple Input Multiple Output (MIMO) omnidirectional antenna confugrations, various bandwidth sizes, Adaptive Modulation and Coding (AMC) technique, and multipath selective fading channel conditions through Monte Carlo type simulations. The design of the custom built system level simulator, implementation of various scenarios of the LTE system, and the simulator findings are thoroughly described in the document. The simulator presents an universal framework for performance evaluation of existing and for development of new scheduling algorithms.

Download or read book Radio Resource Management in Wireless Networks written by Ekram Hossain and published by Cambridge University Press. This book was released on 2017-04-27 with total page 433 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book allows readers to gain an in-depth understanding of resource allocation problems in wireless networks and the techniques used to solve them.

Download or read book Radio Resource Management in Multi Tier Cellular Wireless Networks written by Ekram Hossain and published by John Wiley & Sons. This book was released on 2013-12-09 with total page 346 pages. Available in PDF, EPUB and Kindle. Book excerpt: Providing an extensive overview of the radio resource management problem in femtocell networks, this invaluable book considers both code division multiple access femtocells and orthogonal frequency-division multiple access femtocells. In addition to incorporating current research on this topic, the book also covers technical challenges in femtocell deployment, provides readers with a variety of approaches to resource allocation and a comparison of their effectiveness, explains how to model various networks using Stochastic geometry and shot noise theory, and much more.

Download or read book Resource Management for Heterogeneous Wireless Networks written by Amila Tharaperiya Gamage and published by Springer. This book was released on 2017-08-18 with total page 116 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book provides an in-depth discussion on how to efficiently manage resources of heterogeneous wireless networks and how to design resource allocation algorithms to suit real world conditions. Efficiently managing resources of the networks is more crucial now, than ever before, to meet users’ rapidly increasing demand for higher data rates, better quality-of-service (QoS) and seamless coverage. Some of the techniques that can be incorporated within heterogeneous wireless networks to achieve this objective are interworking of the networks, user multi-homing and device-to-device (D2D) communication. Designing resource allocation algorithms to suit real world conditions is also important, as the algorithms should be deployable and perform well in real networks. For example, two of the conditions considered in this book are resource allocation intervals of different networks are different and small cell base stations have limited computational capacity. To address the first condition, resource allocation algorithms for interworking systems are designed to allocate resources of different networks at different time-scales. To address the second condition, resource allocation algorithms are designed to be able to run at cloud computing servers. More of such conditions, algorithms designed to suit these conditions, modeling techniques for various networks and performance analysis of the algorithms are discussed in the book. This book concludes with a discussion on the future research directions on the related fields of study. Advanced-level students focused on communication and networking will use this book as a study guide. Researchers and experts in the fields of networking, converged networks, small-cell networks, resource management, and interference management, as well as consultants working in network planning and optimization and managers, executives and network architects working in the networking industry will also find this book useful as a reference.

Download or read book Modeling and Performance Analysis of Relay based Cooperative Orthogonal Frequency Division Multiple Access Networks written by Md Shamsul Alam and published by . This book was released on 2014 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Next generation wireless communication networks are expected to provide ubiquitous high data rate coverage and support heterogeneous wireless services with diverse quality-of-service (QoS) requirements. This translates into a heavy demand for the spectral resources. In order to meet these requirements, Orthogonal Frequency Division Multiple Access (OFDMA) has been regarded as a promising air-interface for the emerging fourth generation (4G) networks due to its capability to combat the channel impairments and support high data rate. In addition, OFDMA offers flexibility in radio resource allocation and provides multiuser diversity by allowing subcarriers to be shared among multiple users. One of the main challenges for the 4G networks is to achieve high throughput throughout the entire cell. Cooperative relaying is a very promising solution to tackle this problem as it provides throughput gains as well as coverage extension. The combination of OFDMA and cooperative relaying assures high throughput requirements, particularly for users at the cell edge. However, to fully exploit the benefits of relaying, efficient relay selection as well as resource allocation are critical in such kind of network when multiple users and multiple relays are considered. Moreover, the consideration of heterogeneous QoS requirements further complicate the optimal allocation of resources in a relay enhanced OFDMA network. Furthermore, the computational complexity and signalling overhead are also needed to be considered in the design of practical resource allocation schemes. In this dissertation, we conduct a comprehensive research study on the topic of radio resource management for relay-based cooperative OFDMA networks supporting heterogeneous QoS requirements. Specifically, this dissertation investigates how to effectively and efficiently allocate resources to satisfy QoS requirements of 4G users, improve spectrum utilization and reduce computational complexity at the base station. The problems and our research achievements are briefly outlined as follows. Firstly, a QoS aware optimal joint relay selection, power allocation and subcarrier assignment scheme for uplink OFDMA system considering heterogeneous services under a total power constraint is proposed. The relay selection, power allocation and subcarrier assignment problem is formulated as a joint optimization problem with the objective of maximizing the system throughput, which is solved by means of a two level dual decomposition and subgradient method. The computational complexity is finally reduced via the introduction of two suboptimal schemes. The performance of the proposed schemes is demonstrated through computer simulations based on OFDMA network. Numerical results show that our schemes support heterogeneous services while guaranteeing each user's QoS requirements with slight total system throughput degradation. Secondly, we investigate the resource allocation problem subject to the satisfaction of user QoS requirements and individual total power constraints of the users and relays. The throughput of each end-to-end link is modeled considering both the direct and relay links. Due to non-convex nature of the original resource allocation problem, the optimal solution is obtained by solving a relaxed problem via two level dual decomposition. Numerical results reveal that the proposed scheme is effective in provisioning QoS of each user's over the conventional resource allocation counterpart under individual total power constraints of the users and relays . Lastly, decentralized resource allocation schemes are proposed to reduce the computational complexity and CSI feedback overhead at the BS. A user centric distributed (UCD) scheme and a relay centric distributed (RCD) scheme are proposed, where the computation of the centralized scheme is distributed among the users and relays, respectively. We also proposed suboptimal schemes based on simplified relay selection. The suboptimal schemes can be combined with the distributed schemes to further reduce of signalling overhead and computational complexity. Numerical results show that our schemes guarantee user's satisfaction with low computational complexity and signalling overhead, leading to preferred candidates for practical implementation. The research results obtained in this dissertation can improve the resource utilization and QoS assurance of the emerging OFDMA networks.

Download or read book Next Generation Wireless Communications Using Radio over Fiber written by Nathan J. Gomes and published by John Wiley & Sons. This book was released on 2012-08-15 with total page 315 pages. Available in PDF, EPUB and Kindle. Book excerpt: Taking a coherent and logical approach, this book describes the potential use of co-ordinated multipoint systems supported by radio over fiber. It covers an impressive breadth of topics, ranging from components, subsystem and system architecture, to network management and business perspectives. The authors show the importance of radio over fiber in eliminating or mitigating against the current, perceived barriers to the use of co-ordinated multipoint, and the drivers for standardisation activities in future mobile/wireless systems over the next few years. The book brings together the system concept for centralized processing, including what is required for co-existence with legacy wireless systems, the algorithms that can be used for improving wireless bandwidth utilization at physical and MAC layers and the radio over fiber network and link design necessary to support the wireless system. Other important research is also covered as the authors look at compensating for radio over fiber impairments and providing simple network management functions. A study of service provision and the business case for such a future wireless system is also fully considered. This book comes at an important time for future wireless systems with standardization of fourth generation wireless systems still ongoing. The content enables readers to make key decisions about future standardisation and their own research work. The business analysis also makes the book useful to those involved in deciding the future directions of telecoms organisations. This information will be core to their decision-making as it provides technical knowledge of the state-of-the-art but also system level assessments of what is possible in a business environment.

Download or read book Practical Radio Resource Management in Wireless Systems written by Sofoklis A. Kyriazakos and published by Artech House. This book was released on 2004 with total page 262 pages. Available in PDF, EPUB and Kindle. Book excerpt: Despite frustrating customers and loss of revenue for telecommunications providers, cellular network congestion has remained a problem for which few solutions have been found. Covering GSM, GPRS, UMTS and beyond 3G systems, this practical book breaks new ground by providing you with proven techniques for decreasing blocking and dropped call rate due to network congestion. Using real measurements, this book clearly shows you that the maximum traffic that can be accommodated in a wireless network is not a constant value and varies significantly.

Download or read book Resource Allocation for OFDMA Systems written by Chen Chen and published by Springer. This book was released on 2019-06-29 with total page 140 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book introduces the sources and historic collection campaigns of resource allocation in wireless communication systems. The unique characteristics of MIMO-OFDMA systems are thoroughly studied and summarized. Remarks on resource allocation and spectrum sharing are also presented, which demonstrate the great value of resource allocation techniques, but also introduce distinct challenges of resource allocation in MIMO-OFDMA systems. Novel resource allocation techniques for OFDMA Systems are surveyed from various applications (e.g., for unicast, or multicast with Guaranteed BER and Rate, subcarrier and power allocation with various detectors, low-complexity energyefficient resource allocation, etc.) in this book. Due to the high mobility and low latency requirements of 5G wireless communications, this book discusses how to deal with the imperfect CSI. It also discusses how to deal with e.g., throughput maximization, outage probabilities maximization and guarantee, energy efficiency, physical-layer security issues with feedback channel capacity constraints, in order to characterize and understand the applications of practical scenes. This book will target professionals & researchers working in the fields of Wireless Communications and Networking, Resource Allocation and Transmissions. Advanced-level students in electrical engineering and computer science will also find this book useful as a secondary textbook.

Download or read book Radio Resource Management Using Geometric Water Filling written by Peter He and published by Springer Science & Business Media. This book was released on 2014-02-14 with total page 97 pages. Available in PDF, EPUB and Kindle. Book excerpt: This brief introduces the fundamental theory and development of managing radio resources using a water-filling algorithm that can optimize system performance in wireless communication. Geometric Water-Filling (GWF) is a crucial underlying tool in emerging communication systems such as multiple input multiple output systems, cognitive radio systems, and green communication systems. Early chapters introduce emerging wireless technologies and provide a detailed analysis of water-filling. The brief investigates single user and multi-user issues of radio resource management, allocation of resources, and energy harvesting. Effective algorithms demonstrate the incredible potential capabilities of water-filling mechanisms. This brief is designed for researchers and professionals working with resource management and wireless communications. Advanced-level students in computer science and engineering will also find the information valuable.

Download or read book Resource Management in Mobile Computing Environments written by Constandinos X. Mavromoustakis and published by Springer. This book was released on 2014-06-09 with total page 598 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book reports the latest advances on the design and development of mobile computing systems, describing their applications in the context of modeling, analysis and efficient resource management. It explores the challenges on mobile computing and resource management paradigms, including research efforts and approaches recently carried out in response to them to address future open-ended issues. The book includes 26 rigorously refereed chapters written by leading international researchers, providing the readers with technical and scientific information about various aspects of mobile computing, from basic concepts to advanced findings, reporting the state-of-the-art on resource management in such environments. It is mainly intended as a reference guide for researchers and practitioners involved in the design, development and applications of mobile computing systems, seeking solutions to related issues. It also represents a useful textbook for advanced undergraduate and graduate courses, addressing special topics such as: mobile and ad-hoc wireless networks; peer-to-peer systems for mobile computing; novel resource management techniques in cognitive radio networks; and power management in mobile computing systems.

Download or read book Self Organized Radio Resource Management in OFDM Based Cellular Systems written by Ting Chen and published by Cuvillier Verlag. This book was released on 2010-12-14 with total page 124 pages. Available in PDF, EPUB and Kindle. Book excerpt: The OFDM transmission technique brings high efficiency in future wideband mobile communication systems. With self-organized radio resource management, an OFDM based cellular system can reach full flexibility, especially in a network with hotspots. Each base station allocates resources on demand, based on real-time measurements of signal and interference. Neither a central controller nor direct communication between base stations is needed. Additional schemes can be applied to reduce call interruptions due to unpredictable new interference after resource allocation. Future mobile communication systems require higher data rate and more flexibility. The OFDM, as a multi-carrier transmission technique, achieves high efficiency by subdividing the bandwidth into narrow and orthogonal subcarriers with specific spectrums. The consequent long symbol duration enables also a simple receiver structure in a multi-path propagation environment. Moreover, each subcarrier can use independently individual transmission parameters. In this thesis, a scheme of self-organized radio resource management is proposed for an OFDM based cellular system. All base stations in a cellular network are operating in the same central carrier frequency, but with different radio resources. A resource can be defined as a timeslot, a subcarrier, or any frequency-time block. All resources are accessible at any cell in the cellular network. Neither central controllers nor direct communication between base stations is needed. Each base station allocates radio resources and selects transmission parameters independently in accordance with the requirement and the measured real-time network condition. The powers of signal and interference are measured at both base stations and mobile terminals. To have an interference free measurement, a dedicated signal measurement timeslot is designed in the uplink. A resource quality function is defined to predict the transmission result in a time variant channel, applying both adaptive modulation and coding, and link adaptation. Those resources with highest possible data rates are allocated. In this way, an adaptive and up-to-date resource reuse can be realized. To reduce the amount of droppings due to unpredictable new interference after allocation, a security margin is introduced, which reserves a priori a space for new interference. A suitable margin brings 13% capacity increase. More efficiently, a reallocation procedure can be triggered when service degradation is observed for certain duration. This method can even bring about two times more capacity. The SO-RRM shows its high flexibility in a cellular network with non-uniform or fast changing user distribution. Hotspot cells can declare more resources, while the cells with few users use only much less resources. Furthermore, the multi-user diversity enables in the downlink adaptive resource rearrangement. Resources used inside a cell is exchanged based on instantaneous channel condition. Three different algorithms are compared. They can bring about 80% spectrum higher efficiency. Further information: - Tsinghua University (Chinese) - Tsinghua University (English) - Ruijie Networks Co., Ltd (Chinese) - Ruijie Networks Co., Ltd (English)

Download or read book Optimization Methods for User Admissions and Radio Resource Allocation for Multicasting over High Altitude Platforms written by Ibrahim, Ahmed and published by River Publishers. This book was released on 2019-02-27 with total page 154 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book focuses on the issue of optimizing radio resource allocation (RRA) and user admission control (AC) for multiple multicasting sessions on a single high altitude platform (HAP) with multiple antennas on-board. HAPs are quasi-stationary aerial platforms that carry a wireless communications payload to provide wireless communications and broadband services. They are meant to be located in the stratosphere layer of the atmosphere at altitudes in the range 17-22 km and have the ability to fly on demand to temporarily or permanently serve regions with unavailable telecommunications infrastructure. An important requirement that the book focusses on is the development of an efficient and effective method for resource allocation and user admissions for HAPs, especially when it comes to multicasting. Power, frequency, space (antennas selection) and time (scheduling) are the resources considered in the problem over an orthogonal frequency division multiple access (OFDMA) HAP system. Due to the strong dependence of the total number of users that could join different multicast groups, on the possible ways we may allocate resources to these groups, it is of significant importance to consider a joint user to session assignments and RRA across the groups. From the service provider's point of view, it would be in its best interest to be able to admit as many higher priority users as possible, while satisfying their quality of service requirements. High priority users could be users subscribed in and paying higher for a service plan that gives them preference of admittance to receive more multicast transmissions, compared to those paying for a lower service plan. Also, the user who tries to join multiple multicast groups (i.e. receive more than one multicast transmission), would have preferences for which one he would favor to receive if resources are not enough to satisfy the QoS requirements. Technical topics discussed in the book include: Overview on High Altitude Platforms, their different types and the recent works in this areaRadio Resource Allocation and User Admission Control in HAPsMulticasting in a Single HAP System: System Model and Mathematical FormulationOptimization schemes that are designed to enhance the performance of a branch and bound technique by taking into account special mathematical structure in the problem formulation

Download or read book Radio Resource Management Based on Genetic Algorithms for OFDMA Networks written by Dapeng Zhang and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: OFDMA will be the multiple access scheme for next generation networks, including LTE and LTE-A. These networks will provide higher data rates than now, up to several hundred Mbps. These new networks, using a higher carrier frequency and offering flexible bandwidth for different application types, require advanced techniques for radio resource management. One approach that has been suggested to improve the radio resource management is to use smart and semi-smart antennas, so that the coverage of a certain cell can be divided into several adjustable sectors by using different antenna patterns. However, for a multi-cell environment, there is a need to prevent there being a gap between adjacent cells as the antenna patterns change. In this work, Genetic Algorithms are used to optimize the antenna patterns to get better coverage together with better cell throughput, at the same time making sure there are no gaps. This thesis not only considers the overall problem, but also investigates the suitability of the Genetic Algorithm itself, with it being optimized to improve the performance of the radio resource management in LTE networks. The influence of selection rate and mutation rate on GA is investigated and tested by simulation. These Genetic Algorithms are used in a model of multi-cell LTE networks to optimise subchannel allocation combined with dynamic sectorisation. Different types of scenarios are considered and the Genetic Algorithm is used to solve the problem of combining subchannel allocation with dynamic sectorisation to give the best overall performance of the LTE network.

Download or read book Dynamic Spectrum Access and Management in Cognitive Radio Networks written by Ekram Hossain and published by Cambridge University Press. This book was released on 2009-06-18 with total page 504 pages. Available in PDF, EPUB and Kindle. Book excerpt: An all-inclusive introduction to this revolutionary technology, presenting the key research issues and state-of-the-art design, analysis, and optimization techniques.

Download or read book Radio Resource Management Strategies in UMTS written by Jordi Perez Romero and published by John Wiley & Sons. This book was released on 2005-10-31 with total page 364 pages. Available in PDF, EPUB and Kindle. Book excerpt: The key feature of future mobile communication systems is the ability to deliver wideband and high bit-rate multimedia services alongside the traditional radio services such as voice, messaging and slow rate data. The broad range of services expected to be supported can be divided into different Quality of Service (QoS) classes. However, the provision of such mobile multimedia services under QoS guarantees will not be possible without a utilization of the air interface resources by means of Radio Resource Management (RRM) strategies that ensure the target QoS, the planned coverage area and that offer a high system capacity. Under this framework, the book focuses on the RRM concepts, including the theoretical background that serves as a basis for the description of specific RRM algorithms. The RRM problem for UMTS is presented, and more specifically, for the FDD mode, which is based on a WCDMA scheme. More specifically, the different aspects that are covered include: Introduces the mobile communications sector and UMTS, including the evolution towards 4G systems, with an overview of the QoS concept which is key for the definition of RRM strategies Offers a detailed description of the radio interface in UMTS, as the basis for the implementation of RRM strategies Provides the fundamental concepts related with the development of RRM strategies in WCDMA networks Analyses particular RRM algorithms in a variety of scenarios, trying to identify the key parameters and factors that influence their performance Explores the evolution of UMTS towards Beyond 3G systems and the concept of Common RRM in heterogeneous networks with the aid of some algorithm examples This comprehensive title is essential reading for engineers and managers in radio engineering departments of UMTS network operators and UMTS equipment manufacturers. It will also prove insightful to researchers in the field of 3G and Beyond 3G systems and academics in any of these areas.