Download or read book Interference Characterization and Suppression for Multiuser Direct sequence Spread spectrum System written by Mingxi Fan and published by . This book was released on 2002 with total page 184 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this thesis we investigate efficient modulation and detection techniques for the uplink (i.e. transmission from mobile to base station) of a DS-CDMA network. Specifically, the thesis contains three parts. In the first part, we focus on the mobile transmitter. In particular, we evaluate and compare the spectral efficiency of two promising variable rate DS-CDMA transmission techniques, multicode (MCD) and variable-spreading-gain (VSG), under the presence of multiple-access (user-to-user) interferences (MAI) and multipath interferences. The uniqueness of our study is that in bit-error-rate evaluation, instead of approximating the interference as Gaussian noise (which has been done in most of the previous studies), we incorporate both power and distribution of interferences into consideration. We show where the Gaussian assumption may give misleading answers and how our results in these cases are different from those obtained in the past. In part two and three of the thesis, we focus on the base station receiver. Specifically, we present effective joint detection techniques that have good performance-complexity tradeoff. Part two of the thesis introduces a class of novel multistage parallel interference cancellation algorithms based on stage-by-stage minimum mean-squared error (MMSE) optimization. We show that this scheme is capable of achieving significantly better performance than other algorithms with similar complexity. Part three of the thesis presents a low-complexity dual-mode multiuser detector that dynamically switches its detection mode between the matched-filter receiver and the decorrelator. We show that this detector is capable of achieving the performance of a decorrelator but with significant savings in processing power and complexity.
Download or read book Multiple Access Interference Characterization for Direct Sequence Spread Spectrum Communications Using Chip Waveform Shaping written by Matthew G. Glen and published by . This book was released on 2004-03-01 with total page 78 pages. Available in PDF, EPUB and Kindle. Book excerpt: This research characterizes MAI effects on DS/SSMA system performance through simulation in Matlab , and explores the impact of multiple access code selection, chip waveform shaping, and multiple access code length on BER for both synchronous and asynchronous multiple access networks. In addition, the simulated DS/SSMA model permits rapid research into the effects of additional factors on BER. Prior to experimental testing, model validation is conducted through single user trials and by comparison with existing research for similar system designs. For synchronous and asynchronous networks, Gold coding improves BER by 7.5 and 4.0 dB, respectively, relative to aperiodic random spreading codes. Synchronous network results show that chip waveform shaping provides no significant BER improvement for the Blackman or Lanczos shapes. However, asynchronous network results show a potential BER improvement for Blackman and Lanczos shapes. Increasing code length from 31 to 511 resulted in a 7.5 dB BER improvement. Collectively, these results directly relate changes in BER to waveform cross-correlation statistics.
Download or read book Interference Analysis and Reduction for Wireless Systems written by Peter Stavroulakis and published by Artech House. This book was released on 2003 with total page 442 pages. Available in PDF, EPUB and Kindle. Book excerpt: This leading-edge resource offers you a new methodology for analyzing and studying the behavior of wireless communication systems in an interference environment. It provides you with modern tools and techniques for use in real-world applications that help you guarantee optimum system performance. The book treats both additive and multiplicative interfering signals, including in-depth descriptions of how these signals behave, regardless of the source.
Download or read book Narrowband and Multiple Access Interference Suppression for Direct Sequence Spread Spectrum Communication Receivers written by and published by . This book was released on 1998 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report presents research results focused on the mitigation of both narrowband and multiple access interference in direct sequence spread spectrum communication systems. Both linear and nonlinear adaptive algorithmic approaches are developed and reported. Specific attention has been paid to making the algorithmic practicable. In addition to the algorithmic development, a software simulation for a code division multiple access system is developed using a commercially available programming environment.
Download or read book Multiuser Detection written by Sergio Verdú and published by Cambridge University Press. This book was released on 1998-08-13 with total page 478 pages. Available in PDF, EPUB and Kindle. Book excerpt: Originally published in 1998, Multiuser Detection provides a comprehensive treatment of the subject of multiuser digital communications.
Download or read book Improved Statistical Interference Suppression Techniques in Single and Multi rate Direct Sequence Spread Spectrum Code Division Multiple Access Systems written by Beibei Wang and published by . This book was released on 2007 with total page 280 pages. Available in PDF, EPUB and Kindle. Book excerpt: We first present a statistical parallel interference cancellation (STPIC) technique. Here we propose two different methods: instantaneous STPIC (ISTPIC), in which IC is performed only on the bits whose absolute log likelihood ratio (LLR) is below a pre-selected threshold, and block STPIC (BSTPIC), in which IC is performed only on the blocks whose average signal-to-interference-plus-noise-ratio (SINR) is below a pre-selected threshold. Both LLR and SINR statistics reduce to quantities simple to obtain. It has been shown that both ISTPIC and BSTPIC can achieve performance similar to or better than conventional full PIC (FPIC), but with significantly reduced computational complexity. It is also shown that the proposed ISTPIC has larger performance gain than conventional FPIC in higher loading case where efficient interference cancellation techniques are mostly needed. We also propose a new generalized soft limiter (GSL) that combines the advantage of hard decision and partial soft decision. In GSL, hard decisions are made on "reliable" signals with absolute amplitudes larger than a threshold, whereas partial soft decisions are made on "unreliable" signals with absolute amplitudes less than the threshold. We have shown that PIC using the proposed GSL has performance similar to that using hyperbolic tangent decision, which has been shown to be the optimal decision in the single user case with Gaussian interference and noise, but with easier implementation. Furthermore, we propose new techniques that combine the STPIC with partial PIC or other improved decision techniques, which have shown to be capable of achieving performance similar to or better than original techniques with reduced computational complexity. We also evaluate and compare the performance of different PIC techniques in the presence of imperfect channel estimation and near-far effects. Performance analysis and comparison of different PIC techniques have also been done in multi-rate DS-CDMA systems with different schemes: variable spreading gain, multi-code, and variable chip rate. Finally, we review narrowband interference (NBI) suppression techniques and investigate the performance of a decision feedback scheme aided by the proposed GSL-PIC in the presence of NBI.
Download or read book Performance Analysis of Interference Suppression Techniques for Multiple Antenna Systems written by Patrick Amihood and published by . This book was released on 2007 with total page 135 pages. Available in PDF, EPUB and Kindle. Book excerpt: Finally, we consider the effects of channel estimation errors on the performance of a system employing Tomlinson-Harashima precoding and the QR decomposition, operating over MISO frequency-flat fading channels with decentralized receivers. The QR decomposition of the channel matrix is employed to arrive at an equivalent channel where successive interference cancellation at the transmitter can be used to remove the effect of the multiuser interference.
Download or read book Narrowband Interference Suppression Techniques Using Decision Feedback Filtering in Direct Sequence Spread Spectrum Systems written by Katherine Jauregui Lovette and published by . This book was released on 1994 with total page 108 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Advanced Wireless Communications written by Savo G. Glisic and published by John Wiley & Sons. This book was released on 2007-06-13 with total page 890 pages. Available in PDF, EPUB and Kindle. Book excerpt: Fully revised and updated version of the successful "AdvancedWireless Communications" Wireless communications continue to attract the attention ofboth research community and industry. Since the first edition waspublished significant research and industry activities have broughtthe fourth generation (4G) of wireless communications systemscloser to implementation and standardization. "Advanced Wireless Communications" continues to provide acomparative study of enabling technologies for 4G. This secondedition has been revised and updated and now includes additionalinformation on the components of common air interface, includingthe area of space time coding , multicarrier modulation especiallyOFDM, MIMO, cognitive radio and cooperative transmission. Ideal for students and engineers in research and development inthe field of wireless communications, the second edition ofAdvanced Wireless Communications also gives an understanding tocurrent approaches for engineers in telecomm operators, governmentand regulatory institutions. New features include: Brand new chapter covering linear precoding in MIMO channelsbased on convex optimization theory. Material based on game theory modelling encompassing problemsof adjacent cell interference, flexible spectra sharing andcooperation between the nodes in ad hoc networks. Presents and discusses the latest schemes for interferencesuppression in ultra wide band (UWB) cognitive systems. Discusses the cooperative transmission and more details onpositioning.
Download or read book Advanced Wireless Communications and Internet written by Savo G. Glisic and published by John Wiley & Sons. This book was released on 2011-05-03 with total page 1025 pages. Available in PDF, EPUB and Kindle. Book excerpt: ADVANCED WIRELESS COMMUNICATIONS AND INTERNET THIRD EDITION ADVANCED WIRELESS COMMUNICATIONS AND INTERNET Future Evolving Technologies The new edition of Advanced Wireless Communications: 4G Cognitive and Cooperative Broadband Technology, 2nd Edition, including the latest developments In the evolution of wireless communications, the dominant challenges are in the areas of networking and their integration with the Future Internet. Even the classical concept of cellular networks is changing and new technologies are evolving to replace it. To reflect these new trends, Advanced Wireless Communications & INTERNET builds upon the previous volumes, enhancing the existing chapters, and including a number of new topics. Systematically guiding readers from the fundamentals through to advanced areas, each chapter begins with an introductory explanation of the basic problems and solutions followed with an analytical treatment in greater detail. The most important aspects of new emerging technologies in wireless communications are comprehensively covered including: next generation Internet; cloud computing and network virtualization; economics of utility computing and wireless grids and clouds. This gives readers an essential understanding of the overall environment in which future wireless networks will be operating. Furthermore, a number of methodologies for maintaining the network connectivity, by using tools ranging from genetic algorithms to stochastic geometry and random graphs theory, and a discussion on percolation and connectivity, are also offered. The book includes a chapter on network formation games, covering the general models, knowledge based network formation games, and coalition games in wireless ad hoc networks. Illustrates points throughout using real-life case studies drawn from the author’s extensive international experience in the field of telecommunications Fully updated to include the latest developments, key topics covered include: advanced routing and network coding; network stability control; relay-assisted Wireless Networks; multicommodity flow optimization problems, flow optimization in heterogeneous networks, and dynamic resource allocation in computing clouds Methodically guides readers through each topic from basic to advanced areas Focuses on system elements that provide adaptability and re-configurability, and discusses how these features can improve wireless communications system performance Enjoyed this book? Why not tell others about it and write a review on your favourite online bookseller.
Download or read book Principles of Spread Spectrum Communication Systems written by Don Torrieri and published by Springer Nature. This book was released on 2022-04-12 with total page 715 pages. Available in PDF, EPUB and Kindle. Book excerpt: This textbook, now in its 5th edition, provides updated state-of-the-art coverage of spread-spectrum communication systems with new applications throughout the book. In this edition, the author extends sections with more comprehensive details about many topics. Some of the more complex sections have been rewritten to make them easier to understand. New subsections, sections, figures, and problems have been added throughout the book. New or expanded topics include frequency-hopping systems with multisymbol CPFSK detection, derivations of spread-spectrum systems with differential data modulations, chaotic systems, channel-state information, and MIMO. As with previous edition, the author presents mathematical analyses of spread-spectrum systems that provide insights into their operations and limitations and are of theoretical and practical interest to both researchers and system designers. He includes updated problems at the end of each chapter, which are intended to assist readers in consolidating their knowledge and to give practice in analytical techniques. Eight appendices provide the mathematical tools that are useful in understanding the main text.
Download or read book Narrowband Interference Rejection Techniques in Direct Sequence Spread Spectrum Systems written by Ronald Athelstan Iltis and published by . This book was released on 1984 with total page 328 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Proceedings of the 2nd National Conference on Emerging Trends in Information Technology eIT 2007 written by Amol C. Goje and published by I. K. International Pvt Ltd. This book was released on 2013-12-30 with total page 358 pages. Available in PDF, EPUB and Kindle. Book excerpt: Information Technology skill standards provide a common language for industry and education. It provides increased portability depending on attitude and performance of the professionals. The industry recognizes IT education programs that build competency among the students to perform the best in the new emerging trends in Information Technology. like Human Computer Interactions, Biometrics, Bioinformatics, Signal Processing. So this conference is organized to bring together leading academicians, industry experts and researchers in the area of emerging trends in Information Technology and facilitate personal interaction and discussions on various aspects of Information Technology. It also aims to provide a platform for the post-graduate students and research students to express their views about the emerging trends in Information Technology with interaction and exchange of ideas among the researchers and students from allover India. With this focus Technical/research papers are invitedfrom the students of MCA/ M.Sc (CS) / M.Sc.(IT)/ MCM and research students on the following topics. Biometrics Data Communication and Security Digital Image and Image Processing Human Computer Interaction Internet Technologies and Service Oriented Architecture Artificial Intelligence and Its Applications
Download or read book American Doctoral Dissertations written by and published by . This book was released on 2002 with total page 776 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Analysis of Interference Excision Algorithms for Direct Sequence Spread Spectrum Signals written by Harvey Hum and published by . This book was released on 1994 with total page 358 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book An Experimental Approach to CDMA and Interference Mitigation written by Luca Fanucci and published by Springer Science & Business Media. This book was released on 2007-05-08 with total page 284 pages. Available in PDF, EPUB and Kindle. Book excerpt: An Experimental Approach to CDMA and Interference Mitigation was written with the admittedly ambitious intent of filling the gap between communication theory and VLSI implementation, and thus to provide a more general/theoretical approach to the design, development, and testing of a CDMA receiver. As a consequence, the concepts and techniques that are presented turn out to be applicable to a more general kind of digital wireless modems in terms of receiver architecture design and implementation. As the reader will easily find out, the subject of digital modem design and implementation is addressed in the book starting from a theoretical approach (supported by proper bibliographic references), and is followed by application issues, with reference to an ESA experiment assumed as a case study. A complete design flow, from specification to implementation, including testing and final verification is then presented. This leads the reader step-by-step to a thorough understanding of CDMA transmission and detection, and constitutes a practical guidance for the design of VLSI wireless mobile terminals.
Download or read book MIMO Wireless Networks written by Bruno Clerckx and published by Academic Press. This book was released on 2013-01-23 with total page 773 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book is unique in presenting channels, techniques and standards for the next generation of MIMO wireless networks. Through a unified framework, it emphasizes how propagation mechanisms impact the system performance under realistic power constraints. Combining a solid mathematical analysis with a physical and intuitive approach to space-time signal processing, the book progressively derives innovative designs for space-time coding and precoding as well as multi-user and multi-cell techniques, taking into consideration that MIMO channels are often far from ideal.Reflecting developments since the first edition was published, this book has been thoroughly revised, and now includes new sections and five new chapters, respectively dealing with receiver design, multi-user MIMO, multi-cell MIMO, MIMO implementation in standards, and MIMO system-level evaluation. Extended introduction to multi-dimensional propagation, including polarization aspects Detailed and comparative description of physical models and analytical representations of single- and multi-link MIMO channels, covering the latest standardized models Thorough overview of space-time coding techniques, covering both classical and more recent schemes under information theory and error probability perspectives Intuitive illustration of how real-world propagation affects the capacity and the error performance of MIMO transmission schemes Detailed information theoretic analysis of multiple access, broadcast and interference channels In-depth presentation of multi-user diversity, resource allocation and (non-)linear MU-MIMO precoding techniques with perfect and imperfect channel knowledge Extensive coverage of cooperative multi-cell MIMO-OFDMA networks, including network resource allocation optimization, coordinated scheduling, beamforming and power control, interference alignment, joint processing, massive and network MIMO Applications of MIMO and Coordinated Multi-Point (CoMP) in LTE, LTE-A and WiMAX Theoretical derivations and results contrasted with practical system level evaluations highlighting the performance of single- and multi-cell MIMO techniques in realistic deployments
