Resource Allocation in Multiuser Multicarrier Wireless Systems

Resource Allocation in Multiuser Multicarrier Wireless Systems PDF Author: Ian C. Wong
Publisher: Springer Science & Business Media
ISBN: 0387749454
Category : Technology & Engineering
Languages : en
Pages : 126

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Book Description
This book proposes a unified algorithmic framework based on dual optimization techniques that have complexities that are linear in the number of subcarriers and users, and that achieve negligible optimality gaps in standards-based numerical simulations. Adaptive algorithms based on stochastic approximation techniques are also proposed, which are shown to achieve similar performance with even much lower complexity. All the algorithms proposed are clearly presented in concise block diagrams allowing the reader to implement these algorithms in the software of their choice. This book is an accessible reference for researchers and industry practitioners alike.

Resource Allocation in Multiuser Multicarrier Wireless Systems

Resource Allocation in Multiuser Multicarrier Wireless Systems PDF Author: Ian C. Wong
Publisher: Springer Science & Business Media
ISBN: 0387749454
Category : Technology & Engineering
Languages : en
Pages : 126

Get Book Here

Book Description
This book proposes a unified algorithmic framework based on dual optimization techniques that have complexities that are linear in the number of subcarriers and users, and that achieve negligible optimality gaps in standards-based numerical simulations. Adaptive algorithms based on stochastic approximation techniques are also proposed, which are shown to achieve similar performance with even much lower complexity. All the algorithms proposed are clearly presented in concise block diagrams allowing the reader to implement these algorithms in the software of their choice. This book is an accessible reference for researchers and industry practitioners alike.

Resource Allocation in Multiuser Multicarrier Wireless Systems

Resource Allocation in Multiuser Multicarrier Wireless Systems PDF Author: Ian C. Wong
Publisher: Springer
ISBN: 9780387521176
Category : Technology & Engineering
Languages : en
Pages : 0

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Book Description
This book proposes a unified algorithmic framework based on dual optimization techniques that have complexities that are linear in the number of subcarriers and users, and that achieve negligible optimality gaps in standards-based numerical simulations. Adaptive algorithms based on stochastic approximation techniques are also proposed, which are shown to achieve similar performance with even much lower complexity. All the algorithms proposed are clearly presented in concise block diagrams allowing the reader to implement these algorithms in the software of their choice. This book is an accessible reference for researchers and industry practitioners alike.

A Unified Framework for Optimal Resource Allocation in Multiuser Multicarrier Wireless Systems

A Unified Framework for Optimal Resource Allocation in Multiuser Multicarrier Wireless Systems PDF Author: Ian Chan Wong
Publisher:
ISBN: 9780549070863
Category :
Languages : en
Pages : 170

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Book Description
Finally, it was assumed in previous work that perfect channel state information (CSI) is available at the transmitter, which is quite unrealistic due to inevitable channel estimation errors and feedback delay. This dissertation develops algorithms assuming that only imperfect CSI is available, such that allocation decisions are made while explicitly considering the error statistics of the CSI.

Dynamic Resource Allocation in Multiuser Multicarrier Fading Environments

Dynamic Resource Allocation in Multiuser Multicarrier Fading Environments PDF Author: Yang Xu
Publisher:
ISBN:
Category :
Languages : en
Pages :

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Book Description
"Interference among users results in the degradation of signal quality and leads to poor performance in multi-user interference systems such as DSL system, ad-hoc wireless network. Study of the interaction of interference among users in the network is crucial for achieving better system performance. Efficient utilization of available resources in an interference system has two major complementary approaches: interference cancellation and resource allocation. The principal objective of this thesis is to develop efficient resource allocation algorithms that can optimize joint perfounance of multiple users in multi-user multi-carrier interference channels. Such resource allocation problems in multi-user interference channels can be formulized as nonconvex optimization problems. The search for the optimal solution is very challenging for these problems: conventional local optimization techniques are only capable of finding local optimum; In addition, resource allocation problems encountered in practice generally are large-scale ones, as the number of users or the number of sub-carriers in the system is typically large. For instance, digital subscriber lines (DSL) system, which is employed as a motivating practical model in this dissertation, has thousands of sub-carriers and large number of lines residing in a binder that cause interference to each other. Designing distributed and centralized resource allocation strategies to achieve good optimality and complexity tradeoff for multi-user interference systems by exploiting the underlining problem structures is the main focus of this thesis. This thesis develops two dynamic resource allocation strategies, responding to different requirements that might arise in various practical scenarios of DSL environment: one is a low-complexity, quasi-distributed algorithm that achieves near-optimal performance with very little centralized coordination; the other is a centralized algorithm based on global difference of convex (d.c.) optimization that guarantees optimal performance with substantial complexity reduction. Our global d.c. approach reveals the hidden convexity of nonconvex optimization problems in interference systems, which were once thought of completely being devoid of any convexity structure. The d.c. structure provides a general framework for designing efficient global optimization algorithm for resource allocation in multi-user interference channel. In particular, a modified prismatic branch and bound (PBnB) is proposed to find global optimum efficiently and its global convergence is also established by analysis. Furthermore, motivated by the observation that the excessive transmission power penalty incurred by zero forcing (ZF) precoding scheme with user selection algorithm for MIMO Broadcast (BC) channels contributing to sum-rate capacity loss, we also explore joint power allocation and interference pre-cancellation (precoding) for wireless MIMO BC channels. A channel inversion regularization (CIR) strategy is proposed to replace ZF as the precoding scheme to alleviate the excessive transmission power penalty and we formulate the maximization of the sum-rate capacity with CIR precoding into d.c. structure and thereafter its global optimum can be achieved with PBnB algorithm. Moreover, we propose a local optimization method based on gradient projection (GP) to achieve near-optimal solution efficiently and we also conduct asymptotic analysis to show that the proposed CIR precoding scheme can achieve asymptotically optimum sum rate equal to that of dirty paper coding (DPC) strategy."--

Multi-Carrier Techniques for Broadband Wireless Communications

Multi-Carrier Techniques for Broadband Wireless Communications PDF Author: Man-On Pun
Publisher: Imperial College Press
ISBN: 1860949479
Category : Computers
Languages : en
Pages : 272

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Book Description
Multi-Carrier Techniques for Broadband Wireless Communications provides an accessible introduction to OFDM-based systems from a signal processing perspective. The first part presents a concise treatment of some fundamental concepts related to wireless communications and multicarrier systems, while the second offers a comprehensive survey of recent developments on a variety of critical design issues. These include synchronization techniques, channel estimation methods, adaptive resource allocation and practical schemes for reducing the peak-to-average power ratio of the transmitted waveform.

Resource Allocation for Wireless Networks

Resource Allocation for Wireless Networks PDF Author: Zhu Han
Publisher: Cambridge University Press
ISBN: 9780521873857
Category : Technology & Engineering
Languages : en
Pages : 558

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Book Description
Merging the fundamental principles of resource allocation with the state-of-the-art in research and application examples, Han and Liu present a novel and comprehensive perspective for improving wireless systems performance. Cross-layer multiuser optimization in wireless networks is described systematically. Starting from the basic principles, such as power control and multiple access, coverage moves to the optimization techniques for resource allocation, including formulation and analysis, and game theory. Advanced topics such as dynamic resource allocation and resource allocation in antenna array processing, and in cooperative, sensor, personal area, and ultrawideband networks, are then discussed. Unique in its scope, timeliness, and innovative author insights, this invaluable work will help graduate students and researchers to understand the basics of wireless resource allocation whilst highlighting modern research topics, and will help industrial engineers to improve system optimization.

Scheduling and Resource Allocation in Multi-user Wireless Systems

Scheduling and Resource Allocation in Multi-user Wireless Systems PDF Author: Xuan Wang
Publisher:
ISBN:
Category :
Languages : en
Pages :

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Book Description
In this dissertation, we discuss various aspects of scheduling and resource allocation in multi-user wireless systems. This work starts from how to utilize advanced physical-layer technology to improve the system performance in a multi-user environment. We show that by using superposition coding (SPC) and successive interference cancellation, the system performance can be greatly improved with utility-based scheduling. Several observations are made as the design guideline for such system. Scheduling algorithms are designed for a system with hierarchical modulation which is a practical implementation of SPC. However, when the utility-based scheduling is designed, it is based on the assumption that the system is saturated, {\em i.e.}, users in the system always have data to transmit. It is pointed out in the literature that in a system with stochastic traffic, even if the arrival rate lies inside the capacity region, the system in terms of queue might not be stable with the utility-based scheduling. Motivated by this, we have studied the stability region of a general utility-based scheduling in a multi-user system with stochastic traffic. We show that the stability region is generally less than the capacity region, depends on how to interpret an intermediate control variable, and the resultant stability region may be even non-convex and exhibits undesirable properties which should be avoided. As the utility-based scheduling cannot achieve throughput-optimal, we turn our attentions to the throughput-optimal scheduling algorithms, whose stability region is identical to the capacity region. The limiting properties of an overloaded wireless system with throughput-optimal scheduling algorithms are studied. The results show that the queue length is unstable however the scheduling function of the queue length is stable, and the average throughput of the system converges. Finally we study how to schedule users in a multi-user wireless system with information-theoretic security support, which is focused on the secrecy outage probability. The problem is essentially about how to schedule users, and allocate resources to stabilize the system and minimize the secrecy outage probability. We show that there is a tradeoff between the arrival rate of the traffic and the secrecy outage probability. The relative channel condition of the eavesdropper also plays an important role to the secrecy outage probability. In summary, we showed utility-based scheduling using SPC can improve the system performance greatly, but the utility-based scheduling has limitations: the stability region might not have desired properties. On the contrary throughput-optimal scheduling has its own drawbacks: the traffic cannot be handled properly if the system is overloaded. The further study on the secrecy outage probability gives guideline on how to design a scheduler in a system with information-theoretic security support.

Resource Allocation in Uplink OFDMA Wireless Systems

Resource Allocation in Uplink OFDMA Wireless Systems PDF Author: Elias Yaacoub
Publisher: John Wiley & Sons
ISBN: 1118074505
Category : Technology & Engineering
Languages : en
Pages : 298

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Book Description
Tackling problems from the least complicated to the most, Resource Allocation in Uplink OFDMA Wireless Systems provides readers with a comprehensive look at resource allocation and scheduling techniques (for both single and multi-cell deployments) in uplink OFDMA wireless networks relying on convex optimization and game theory to thoroughly analyze performance. Inside, readers will find topics and discussions on: Formulating and solving the uplink ergodic sum-rate maximization problem Proposing suboptimal algorithms that achieve a close performance to the optimal case at a considerably reduced complexity and lead to fairness when the appropriate utility is used Investigating the performance and extensions of the proposed suboptimal algorithms in a distributed base station scenario Studying distributed resource allocation where users take part in the scheduling process, and considering scenarios with and without user collaboration Formulating the sum-rate maximization problem in a multi-cell scenario, and proposing efficient centralized and distributed algorithms for intercell interference mitigation Discussing the applicability of the proposed techniques to state-of-the-art wireless technologies, LTE and WiMAX, and proposing relevant extensions Along with schematics and figures featuring simulation results, Resource Allocation in Uplink OFDMA Wireless Systems is a valuable book for?wireless communications and cellular systems professionals and students.

Optimization Techniques in Resource Allocation of Wireless Communication Systems

Optimization Techniques in Resource Allocation of Wireless Communication Systems PDF Author: K. Sumathi
Publisher: Grin Publishing
ISBN: 9783668359345
Category :
Languages : en
Pages : 64

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Book Description
Scientific Study from the year 2016 in the subject Engineering - Communication Technology, Mahalingam College of Engineering and Technology, language: English, abstract: The future Wireless Communication Systems (WCS) are supposed to provide high data rate to support personal and multimedia communications irrespective of the users' mobility and location. These services include heterogeneous classes of traffics such as voice, file transfer, web browsing, wireless multimedia, teleconferencing, and interactive games. In recent years, data and multimedia services have become important in wireless communications. As a result, bandwidth requirement and number of users become delicate problems. To support high data rate requirement for future WCS, it is essential to efficiently allocate the limited resources. The major challenges are the dynamic nature of wireless channel, limited resources such as power, frequency spectrum, and diversified Quality of Service (QoS) requirements. Orthogonal Frequency Division Multiplexing (OFDM) is a special case of multicarrier transmission that supports high data rate operation. OFDM is a modulation and multiplexing technique appropriate for current and future wireless networks. OFDM divides the available bandwidth into a number of parallel independent orthogonal subchannels and their bandwidth is much less than the coherence bandwidth of the channel. The wide band frequency selective fading channel is converted into several narrow band flat fading channels. OFDM is an excellent method to overcome multipath fading effects. One of the goals of WCS is to enhance the capacity of the channel. Multiple Access Technique (MAT) permits several mobile users to share the given bandwidth in an effective way. Basically there are four multiple access techniques available namely, Time Division Multiple Access (TDMA), Frequency Division Multiple access (FDMA), Code Division Multiple Access (CDMA) and Space Division Multiple Access (SDMA). MAT is employ

Multi-carrier Techniques For Broadband Wireless Communications: A Signal Processing Perspective

Multi-carrier Techniques For Broadband Wireless Communications: A Signal Processing Perspective PDF Author: C-c Jay Kuo
Publisher: World Scientific
ISBN: 1908979046
Category : Technology
Languages : en
Pages : 272

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Book Description
Multi-Carrier Techniques for Broadband Wireless Communications provides an accessible introduction to OFDM-based systems from a signal processing perspective. The first part presents a concise treatment of some fundamental concepts related to wireless communications and multicarrier systems, while the second offers a comprehensive survey of recent developments on a variety of critical design issues. These include synchronization techniques, channel estimation methods, adaptive resource allocation and practical schemes for reducing the peak-to-average power ratio of the transmitted waveform./a