Interference Management Based on Node Cooperation in Multi-user Wireless Networks PDF Download

Author: Daniel Zahavi
Publisher:
ISBN:
Category :
Languages : en
Pages : 204

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Book Description

Author: Venugopal V. Veeravalli
Publisher: Cambridge University Press
ISBN: 131673272X
Category : Technology & Engineering
Languages : en
Pages : 227

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Book Description
Learn about an information-theoretic approach to managing interference in future generation wireless networks. Focusing on cooperative schemes motivated by Coordinated Multi-Point (CoMP) technology, the book develops a robust theoretical framework for interference management that uses recent advancements in backhaul design, and practical pre-coding schemes based on local cooperation, to deliver the increased speed and reliability promised by interference alignment. Gain insight into how simple, zero-forcing pre-coding schemes are optimal in locally connected interference networks, and discover how significant rate gains can be obtained by making cell association decisions and allocating backhaul resources based on centralized (cloud) processing and knowledge of network topology. Providing a link between information-theoretic analyses and interference management schemes that are easy to implement, this is an invaluable resource for researchers, graduate students and practicing engineers in wireless communications.

Author: Frank H. P. Fitzek
Publisher: Springer Science & Business Media
ISBN: 1402047118
Category : Technology & Engineering
Languages : en
Pages : 679

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Book Description
Cooperation in Wireless Networks: Principles and Applications covers the underlying principles of cooperative techniques as well as several applications demonstrating the use of such techniques in practical systems. The book is written in a collaborative manner by several authors from Asia, America, and Europe. This book puts into one volume a comprehensive and technically rich appraisal of the wireless communications scene from a cooperation point of view.

Author: I-Hsiang Wang
Publisher:
ISBN:
Category :
Languages : en
Pages : 388

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Book Description
With the growing number of users along with ever-increasing demand for higher data rates and better quality of service in modern wireless networks, interference has become the major barrier against efficient utilization of limited resources. On the other hand, opportunities for cooperation among radios also increase with the growing number of users, which potentially lead to better interference management. In traditional wireless system design, however, such opportunities are usually neglected and only basic interference management schemes are employed, mainly due to lack of fundamental understanding of interference and cooperation. In this dissertation, we study the fundamental aspects of cooperative interference management through the lens of network information theory. In the first and the second part, we characterize both qualitatively and quantitatively how limited cooperation between transmitting or receiving terminals helps mitigate interference in a canonical two-transmitter-two-receiver wireless system. We identify two regions regarding the gain from limited cooperation: linear and saturation regions. In the linear region cooperation is efficient and provides a degrees-of-freedom gain, which is either one cooperation bit buys one bit over the air or two cooperation bits buy one bit over the air until saturation. In the saturation region cooperation is inefficient and only provides a bounded power gain. The conclusions are drawn from the approximate characterization of the capacity regions. In the third part, we investigate how intermediate relay nodes help resolve interference in delivering information from two sources to their respective destinations in multi-hop wireless networks. We focus on a linear deterministic approximate model for wireless networks, and when the minimum cut value between each source-destination pair is constrained to be 1, we completely characterize the capacity region. One of the interesting findings is that, at most four nodes need to take special coding operations so that interference can be canceled over-the-air or within-a-node, while other nodes can take oblivious operations. We also develop a systematic approach to identify these special nodes.

Author: Ilan Shomorony
Publisher:
ISBN: 9781601989055
Category : Multiuser detection (Telecommunication)
Languages : en
Pages : 131

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Book Description
Multi-hop communication paradigms are expected to play a central role in future wireless networks by enabling a higher spatial reuse of the spectrum. A major challenge in multi-hop multi-user (or multi-flow) wireless networks is that "interference management" and "relaying" are coupled with each other. In other words, wireless relay nodes must play a dual role: they serve as intermediate steps for multi-hop communication and as part of the mechanism that allows interference management schemes. Nonetheless, in the communications, networking and information theory literature, these two tasks have traditionally been addressed separately, and the fundamental principles of the "wireless networks of the future" are currently not well understood. In this monograph, we take a unified approach to relaying and interference management, and seek to develop tools to study the fundamentals of multi-hop multi-flow wireless networks.

Author: Jiandong Li
Publisher: Artech House
ISBN: 1630815098
Category : Technology & Engineering
Languages : en
Pages : 213

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Book Description
This authoritative resource offers a comprehensive overview of heterogeneous wireless networks, small cells, and device-to-device (D2D) communications. The book provides insight into network modeling and performance analysis of heterogeneous wireless networks. Interference management framework and design issues are covered as well as details about resource mobility, channel models, and typical and statistical interference modeling. This resource explains leveraging resource heterogeneity in interference mitigation and presents the challenges and feasible solutions for concurrent transmission. Moreover, complete coverage of interference alignment in MIMO heterogeneous networks for both downlink and uplink is presented. This book provides performance results for an ideal partially connected interference network as well as a practical heterogeneous network. Readers find practical guidance for LTE and LTE-Advanced as well as 5G in this resource. New techniques and designs for heterogeneous wireless networks are included.

Author: Abolfazl Sayed Motahari
Publisher:
ISBN:
Category :
Languages : en
Pages : 146

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Book Description
Spectrum sharing is known as a key solution to accommodate the increasing number of users and the growing demand for throughput in wireless networks. While spectrum sharing improves the data rate in sparse networks, it suffers from interference of concurrent links in dense networks. In fact, interference is the primary barrier to enhance the overall throughput of the network, especially in the medium and high signal-to-noise ratios (SNR's). Managing interference to overcome this barrier has emerged as a crucial step in developing efficient wireless networks. This thesis deals with optimum and sub-optimum interference management-cancelation in non-cooperative networks. Several techniques for interference management including novel strategies such as interference alignment and structural coding are investigated. These methods are applied to obtain optimum and sub-optimum coding strategies in such networks. It is shown that a single strategy is not able to achieve the maximum throughput in all possible scenarios and in fact a careful design is required to fully exploit all available resources in each realization of the system.

Author: Steven Wayne Peters
Publisher:
ISBN:
Category :
Languages : en
Pages : 300

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Book Description
Wireless cellular networks, which serve a large area by geographically partitioning users, suffer from interference from adjacent cells transmitting in the same frequency band. This interference can theoretically be completely mitigated via transceiver cooperation in both the uplink and downlink. Optimally, base stations serving the users can utilize high-capacity backbones. to jointly transmit and receive all the data in the network across all the base stations. In reality, the backbone connecting the base stations is of finite capacity, limiting joint processing to localized clusters. Even with joint processing on a small scale, the overhead involved in sharing data between multiple base stations is large and time-sensitive. Other forms of cooperation have been shown to require less overhead while exhibiting much of the performance benefit from interference mitigation. One particular strategy, called interference alignment (IA), has been shown to exploit all the spatial degrees of freedom in the channel provided data cannot be shared among base stations. Interference alignment was developed for the multi-user interference channel to exploit independent channel observations when all of the links in the network have high signal-to-noise ratio, and assumes all the nodes utilizing the physical resources are participating in the cooperative protocol. When some or all of the links are at moderate signal-to-noise ratio, or when there are non-cooperating users, IA is suboptimal. In this dissertation, I take three approaches to addressing the drawbacks of IA. First, I develop cooperative transmission strategies that outperform IA in various operationg regimes, including at low-to-moderate SNR and in the presence of non-cooperating users. These strategies have the same complexity and overhead as IA. I then develop algorithms for network partitioning by directly considering the overhead of cooperative strategies. Partitioning balances the capacity gains of cooperation with the overhead required to achieve them. Finally, I develop the shared relaying model, which is equivalent to the interference channel but with a single multi-antenna relay mediating communications between transceivers. The shared relay requires less overhead and cooperation than interference alignment but requires added infrastructure. It is shown to outperform conventional relaying strategies in cellular networks with a fixed number of total relay antennas.

Author: Qi Qu
Publisher:
ISBN:
Category :
Languages : en
Pages : 114

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Book Description
In wireless ad-hoc networks, power and spectrum are two limited and precious system resources, and how to use them efficiently is the key to provide high performance communications. This dissertation presents a distributed system design framework and algorithms to achieve power-and-spectrum-efficient wireless communications in ad hoc networks. In the first part, we propose a cross-layer distributed power control and scheduling protocol for delay-constrained applications over mobile CDMA-based ad hoc wireless networks, where power control is employed to combat both the delay occurring on multi-hop wireless ad hoc networks and multiuser interference among mobile users. We also investigate the impact of Doppler spread upon the system performance, and provide a robust system which employs a combination of power control, and coding/interleaving to combat the effects of Doppler spread by exploiting the time diversity when the Doppler spread gets large. In the second part, a cognitive radio based multi-user resource allocation framework for mobile ad hoc networks is proposed. In particular, given pre-existing communications in the spectrum where the system is operating, a channel sensing and estimation mechanism is provided to obtain information such as subcarrier availability, noise power and channel gain. Given this information, both frequency spectrum and power are allocated to emerging new users (i.e., cognitive radio users), based on a distributed multi-user resource allocation framework, in order to achieve spectrum-efficient and power-efficient communications. In the third part, we investigate the issue of cooperative MIMO communications in ad hoc networks, and the issue of cooperative node selection is described, where a source node is surrounded by multiple neighbors and all of them are equipped with a single antenna. Given energy, delay and data rate constraints, a source node dynamically chooses its cooperating nodes from its neighbors to form a virtual MIMO system with the destination node (which is assumed to have multiple antennas), and adaptively allocates the power level and adjusts the constellation size for each of the selected cooperative nodes.

Author: Stefan Berger
Publisher: Logos Verlag Berlin GmbH
ISBN: 383252536X
Category :
Languages : en
Pages : 337

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Book Description
In this thesis, several important aspects of cooperative wireless multiuser networks are investigated. The focus lies on coherent two-hop relaying networks where several amplify-and-forward (AF) relays assist the communication between multiple source-destination pairs. First, the impact of local oscillator (LO) imperfections and I/Q imbalance at the relays on two-hop relaying is investigated. A special focus lies on the comparison between frequency division duplexing (FDD) and time division duplexing (TDD) relays. Based on the observation that the direction in which a channel between two wireless nodes is measured has an impact on the estimate, phase synchronization requirements for coherent relaying networks are then found. Several channel estimation protocols that differ in the direction in which the single-hop channels are measured are furthermore identi'ed and their performance is compared. Next, a very simple phase synchronization scheme is presented that provides a set of relays with a common LO phase. Two coherent beamforming schemes, namely multiuser zero-forcing (MUZF) and multiuser minimum mean squared error (MMSE) relaying, are then investigated. Finally, a real-world demonstrator for distributed wireless communication networks (called RACooN Lab) is presented. It was used to implement coherent cooperative communication schemes on a practical two-hop relaying network.