Download or read book Multicarrier Systems with Antenna Diversity for Wireless Communications written by and published by . This book was released on 2004 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Future wireless communications systems need a high quality of service coupled with high data rate transmission for multimedia services. Achieving this goal in the hostile wireless environment with its limited spectrum has several challenges and implies the necessity of a communication system that is able to increase the channel capacity and overcome the difficulties of the wireless transmission environment with reasonable system complexity. Two of the most enabling technologies for the next generation of wireless systems are orthogonal frequency division multiplexing (OFDM) and multiple-input multiple output (MIMO) systems. MIMO systems have been originally designed for known flat fading channels. In this research, some novel MIMO-OFDM schemes for broadband wireless applications are developed and presented. The objective of the proposed schemes is to enhance the performance of OFDM systems over multipath fading channels by using antenna diversity techniques, and also to make MIMO systems applicable to frequency selective multipath fading channels. For the performance evaluation, both bit error rate (BER) and channel capacity analysis are considered. The channel capacity of MIMO-OFDM systems is analytically evaluated and it is shown that the channel capacity of the these systems can be dramatically increased as a function of the number of antennas. The BER performance of the MIMO-OFDM systems is analytically evaluated. New closed-form expressions for the BER performance of the MIMO-OFDM systems over frequency selective fading channels are derived. On the other hand, the growing popularity of both MIMO and OFDM systems creates the need for adaptive modulation to integrate temporal, spatial and spectral components together. The performance improvement offered by adaptive modulation over non-adaptive systems is remarkable. Furthermore, other dimensions such as frequency and space may yield further gains by providing additional degrees of freedom that can be exploited by

Download or read book Multicarrier Systems with Antenna Diversity for Wireless Communications written by Mohammad Torabi Konjin and published by . This book was released on 2004 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Future wireless communications systems need a high quality of service coupled with high data rate transmission for multimedia services. Achieving this goal in the hostile wireless environment with its limited spectrum has several challenges and implies the necessity of a communication system that is able to increase the channel capacity and overcome the difficulties of the wireless transmission environment with reasonable system complexity. Two of the most enabling technologies for the next generation of wireless systems are orthogonal frequency division multiplexing (OFDM) and multiple-input multiple output (MIMO) systems. MIMO systems have been originally designed for known flat fading channels. In this research, some novel MIMO-OFDM schemes for broadband wireless applications are developed and presented. The objective of the proposed schemes is to enhance the performance of OFDM systems over multipath fading channels by using antenna diversity techniques, and also to make MIMO systems applicable to frequency selective multipath fading channels. For the performance evaluation, both bit error rate (BER) and channel capacity analysis are considered. The channel capacity of MIMO-OFDM systems is analytically evaluated and it is shown that the channel capacity of the these systems can be dramatically increased as a function of the number of antennas. The BER performance of the MIMO-OFDM systems is analytically evaluated. New closed-form expressions for the BER performance of the MIMO-OFDM systems over frequency selective fading channels are derived. On the other hand, the growing popularity of both MIMO and OFDM systems creates the need for adaptive modulation to integrate temporal, spatial and spectral components together. The performance improvement offered by adaptive modulation over non-adaptive systems is remarkable. Furthermore, other dimensions such as frequency and space may yield further gains by providing additional degrees of freedom that can be exploited by adaptive modulation. In this research, a new adaptive modulation scheme for our MIMO-OFDM system (SFBC-OFDM) is presented. The proposed scheme exploits the benefits of space-frequency block codes (SFBC), OFDM and adaptive modulation to provide a high quality of transmission for wireless communications over frequency selective fading channels. It is shown that adaptive modulation can greatly improve the performance of the conventional SFBC-OFDM systems. Finally, a novel antenna selection algorithm is proposed for our MIMO-OFDM system. Three different forms of antenna selection are considered: transmit antenna selection, receive antenna selection, and joint transmit/receive antenna selection. The coding and diversity advantages of the MIMO-OFDM system with antenna selection are examined using average SNR gain, outage probability and BER analysis. The system performance of different forms of the proposed scheme is evaluated and compared. It is shown that the proposed scheme can greatly improve the performance of the conventional SFBC-OFDM systems.

Download or read book Multi Carrier Technologies for Wireless Communication written by Carl R. Nassar and published by Springer Science & Business Media. This book was released on 2006-07-06 with total page 208 pages. Available in PDF, EPUB and Kindle. Book excerpt: Multi-carrier technologies have emerged as important instruments in telecommunications. OFDM is in the forefront, with its adoption by the IEEE 802.11 standards committee and the European HYPERLAN standards group. Following OFDM, MC-CDMA is also demonstrating considerable promise when compared to competing technologies. According to the authors, these technologies are just the beginning in the coming multi-carrier revolution. In Multi-Carrier Technologies for Wireless Communication, the authors explain how a common multi-carrier platform is being designed for DS-CDMA, TDMA, OFDM and MC-CDMA systems. Findings are presented which show how this multi-carrier platform enhances network capacity and probability of error performance.Specific results include (1) innovation in multi-carrier technologies that are enabling them to become an integral part of TDMA and DS-CDMA systems; and (2) the design of multi-carrier systems to overcome PAPR problems (in, e.g., OFDM). Multi-Carrier Technologies for Wireless Communication is an important book for engineers who work with DS-CDMA, TDMA, OFDM, or MC-CDMA systems, and are seeking new ways of exploiting the wireless medium based on a "smarter" signal processing.

Download or read book Orthogonal Frequency Division Multiplexing with Diversity for Future Wireless Systems written by Khoa N. Le and published by Bentham Science Publishers. This book was released on 2012 with total page 621 pages. Available in PDF, EPUB and Kindle. Book excerpt: "The book examines several aspects of Orthogonal Frequency Division Multiplexing (OFDM) employing linear diversity techniques such as inter-carrier interference, bit error rate, peak to average power and inter-block interference. It should be a useful refe"

Download or read book Multiantenna Wireless Communications Systems written by Sergio Barbarossa and published by Artech House Publishers. This book was released on 2005 with total page 480 pages. Available in PDF, EPUB and Kindle. Book excerpt: Antenna diversity has become of critical importance in today's mobile communications systems and this groundbreaking book offers you new approaches to designing transmission strategies for multi-antenna systems. With these novel and practical design strategies you can develop transmission systems that efficiently use available power and bandwidth. The book shows you how to design multi-antenna transceivers in single antenna systems that can reduce transmission power, while ensuring a specified quality level. In addition, you can design wireless networks that have a prescribed degree and probability of connectivity and fault tolerance.

Download or read book Theory and Applications of OFDM and CDMA written by Henrik Schulze and published by John Wiley & Sons. This book was released on 2005-10-31 with total page 420 pages. Available in PDF, EPUB and Kindle. Book excerpt: Theory and Applications of OFDM and CDMA is an ideal foundation textbook for those seeking a sound knowledge of this fast-developing field of wideband communications. The advanced transmission techniques of OFDM, applied in wireless LANs and in digital and video broadcasting, and CDMA, the foundation of 3G mobile communications, have been part of almost every communication system that has been designed in recent years, with both offering a high degree of flexibility in adjusting the system to the requirements of the application and to the impairments caused by the transmission channel. Starting from the basics of digital transmission theory, the reader gains a comprehensive overview of the underlying ideas of these techniques and their strengths and weaknesses under various conditions. In this context, the specific requirements of the mobile radio channel and their relevance for the design of digital transmission systems are discussed and related to the items of channel coding and modulation. Clear explanation of the basics of digital communications, mobile radio channels, coding and modulation, OFDM as a multicarrier system and CDMA as an application of spread spectrum techniques Discusses the most important mobile radio and digital broadcasting systems that use OFDM and CDMA, and explains in detail the underlying ideas for the choice of system parameters Progresses from the fundamentals of wideband communication through to modern applications Includes a Companion Website featuring a solutions manual, electronic versions of the figures and other useful resources This volume will be an invaluable resource to advanced undergraduate students and first/second year postgraduates of electrical and engineering and telecommunications. It will also appeal to practising engineers, researchers and those in academia who wish to expand their knowledge on modern aspects of digital communications and systems in a mobile radio environment.

Download or read book New Directions in Wireless Communications Systems written by Athanasios G. Kanatas and published by CRC Press. This book was released on 2017-10-16 with total page 420 pages. Available in PDF, EPUB and Kindle. Book excerpt: Beyond 2020, wireless communication systems will have to support more than 1,000 times the traffic volume of today's systems. This extremely high traffic load is a major issue faced by 5G designers and researchers. This challenge will be met by a combination of parallel techniques that will use more spectrum more flexibly, realize higher spectral efficiency, and densify cells. Novel techniques and paradigms must be developed to meet these goals. The book addresses diverse key-point issues of next-generation wireless communications systems and identifies promising solutions. The book's core is concentrated to techniques and methods belonging to what is generally called radio access network.

Download or read book Multi antenna Transceiver Techniques for 3G and Beyond written by Ari Hottinen and published by John Wiley & Sons. This book was released on 2004-08-13 with total page 342 pages. Available in PDF, EPUB and Kindle. Book excerpt: Multi-antenna techniques are widely considered to be the most promising avenue for significantly increasing the bandwidth efficiency of wireless data transmission systems. In so called MIMO (multiple input multiple output) systems, multiple antennas are deployed both at the transmitter and the receiver. In MISO (multiple input single output) systems, the receiver has only one antenna, and the multiple transmit antennas are used for transmit diversity. The key aspects of multiple antenna transceiver techniques for evolving 3G systems and beyond are presented. MIMO and MISO (transmit diversity) techniques are explained in a common setting. In particular, the book covers linear processing transmit diversity methods with and without side information at the transmitter (feedback), including the current transmit diversity concepts in the WCDMA standards, as well as promising MIMO concepts, crucial for future high data rate systems. As an example, MIMO and MISO aspects of 3GPP HSDPA (high speed downlink packet access) will be considered. Furthermore, examples of high throughput, low complexity space-time codes will be provided, when signalling without side information (open loop concepts). The theory of linear space-time block codes will be developed, and optimal non-orthogonal high throughput codes will be constructed, both for MIMO and MISO systems. Performance may be further improved by feedback from receiver to transmitter. The corresponding closed loop modes in the current 3GPP specifications will be discussed, along with their extensions for more than two transmit antennas. In addition, feedback signalling for MIMO channels will be addressed. Optimal quantisation methods of the feedback messages will be discussed. Finally, hybrid schemes are constructed, where the amount of feedback is reduced using partly open, partly closed loop signalling. * Provides a concise and up-to-date description of perhaps the most active area of research in wireless communications * Unique in presenting recent developments in both WCDMA and MIMO * MIMO and MISO techniques are explained in a common setting * Special emphasis is placed on combining theoretical understanding with engineering applicability For Research engineers in academia and industry, and development engineers in 3G system design as well as research students.

Download or read book Robust Wireless Communication for Multi antenna Multi rate Multi carrier Systems written by Triet Dang Vo-Huu and published by . This book was released on 2015 with total page 116 pages. Available in PDF, EPUB and Kindle. Book excerpt: Today's trend of migrating radio devices from hardware to software provides potentials to create flexible applications for both commercial and military use. However, this raises security concerns, as malicious attacks can also be alleviated to break legitimate communications. In this research work, we study and build practical systems to mitigate the impact of some serious jamming threats: high-power jamming, rate-based attacks, and jamming in multicarrier systems. First, we develop SAIM—a hybrid system of mixed mechanical steerable antenna and software jamming cancellation—to counter high-power jamming adversary. The system robustness relies on a new antenna structure we specially design for anti-jamming purpose, and a set of new algorithms that can adaptively and effectively mitigate the jamming signal up to 100,000 times higher than legitimate signals. Our solution is appropriate for malicious environments with powerful jammers, where mechanical steering is feasible, e.g., military applications. In residential wireless deployments, even limited-power rate adaptation attacks can dramatically affect the system performance. To tackle this problem, we develop CBM for hiding rate information, and—at the same time—increasing resiliency against jammers up to seven times higher than regular rate-exposing systems. The resiliency boost is achieved by our new generalized non-uniform Trellis Coded Modulation codes, while the modulation and code information is concealed by a new efficient method for cryptographically interleaving baseband symbols. As a third part of this work, we investigate the jamming impact on multicarrier systems with focus on Wi-Fi communications. Toward this goal, we develop the first open source software defined radio Wi-Fi stack that can operate at high rates and allow detailed analysis from Physical Layer to Medium Access Control and Link Layers. Using our platform, we analyze the interleaving process specified by IEEE 802.11 and exploit it to devise an efficient Interleaving Jamming strategy that can totally block the Wi-Fi communications with jamming power less than 1% of the regular transmitted signal power. Our jamming strategy is at least 5dB and up to 15dB more power-efficient than those that are unaware of the Wi-Fi interleaving structure.

Download or read book Distributed Antenna Systems written by Honglin Hu and published by Auerbach Publications. This book was released on 2007-06-27 with total page 504 pages. Available in PDF, EPUB and Kindle. Book excerpt: A technical guide that covers the fundamental concepts, advances and open issues of the Distributed Antenna Systems (DAS). It explores the topic with various key challenges in diverse scenarios, including architecture, capacity, connectivity, scalability, medium access control, scheduling, dynamic channel assignment and cross-layer optimization.

Download or read book Multi Carrier and Spread Spectrum Systems written by Khaled Fazel and published by John Wiley & Sons. This book was released on 2008-09-15 with total page 384 pages. Available in PDF, EPUB and Kindle. Book excerpt: The technological progress in multi-carrier (MC) modulation led orthogonal frequency division multiplexing (OFDM) to become an important part of beyond 3G cellular mobile communication standards, including LTE and WiMAX. In addition, the flexibility offered by the spread spectrum (SS) and time division multiplexing (TDM) techniques motivated many researchers to investigate several MC combined multiple access schemes, such as MC-CDMA, OFDMA and MC-TDMA. These schemes benefit from the advantages of each sub-system and offer high flexibility, high spectral efficiency, simple detection strategies and narrow-band interference rejection capability. Multi-Carrier and Spread Spectrum Systems is one of the first books to describe and analyze the basic concepts of multi-carrier OFDM transmission and its combination with spread spectrum (MC-CDMA). The different architectures and detection strategies as well as baseband-related transceiver components are explained. This includes topics like FEC channel coding and decoding, modulation and demodulation (IFFT/FFT), digital I/Q-generation, time and frequency synchronisation, channel estimation, frequency domain equalization and RF aspects such as phase noise and non-linearity issues. Concrete examples of its applications for cellular mobile communication systems (B3G/4G) are given. Further derivatives of MC-SS (such as OFDMA, SS-MC-MA and DFT-spread OFDM) and their corresponding applications in the LTE, WiMAX, WLAN and DVB-RCT standards are detailed. Capacity and flexibility enhancements of multi-carrier OFDM systems by different MIMO diversity techniques such as space time/frequency coding (STC, SFC) and software defined radio concepts are also described. Written in a highly accessible manner this book provides a unique reference on the topics of multi-carrier and spread spectrum communications, assisting 4G engineers with their implementation. Fully updated new edition of successful text, including two new chapters on LTE and WiMAX Describes in detail new applications of OFDM in mobile communication standards Examines all multi-carrier spread spectrum schemes, with in-depth analysis, from theory to practice Introduces the essentials of important wireless standards based on multi-carrier/spread spectrum techniques.

Download or read book Multicarrier Communications written by Lie-Liang Yang and published by John Wiley & Sons. This book was released on 2009-01-21 with total page 696 pages. Available in PDF, EPUB and Kindle. Book excerpt: Benefiting from both time-domain and frequency-domain signal processing techniques, multicarrier systems have the potential for achieving high spectral-efficiency, high-flexibility and low-complexity wireless communications. Multicarrier techniques therefore constitute the promising techniques for implementation of future generations of wideband, broadband and ultra-wideband systems. Multicarrier Communications offers comprehensive and in-depth evaluation of numerous topics in the area, covering the fundamental principles of spread-spectrum and multicarrier CDMA as well as more advanced topics such as multiuser detection (MUD), multiuser transmitter preprocessing (MUTP), MIMO and space-time processing. It examines OFDM and various multicarrier CDMA within an unified framework and provides analytical approaches and formulas for error-performance evaluation of numerous multicarrier systems. Examines MUD and MUTP in parallel to illustrate the strong duality between receiver optimization and transmitter optimization Comprehensively establishes the theory of noncoherent MUD and noncoherent interference suppression Details the body of knowledge on MIMO theory and space-time multicarrier communications Contains tables, diagrams and figures to illustrate the performance results. Practicing electrical engineers and researchers in wireless communications will find Multicarrier Communications an invaluable guide. It will also be of interest to senior undergraduate and graduate students on wireless communications courses.

Download or read book Multi Carrier and Spread Spectrum Systems written by K. Fazel and published by John Wiley & Sons. This book was released on 2004-02-06 with total page 298 pages. Available in PDF, EPUB and Kindle. Book excerpt: Frequency spectrum is a limited and valuable resource for wireless communications. A good example can be observed among network operators in Europe for the prices to pay for UMTS-frequency bands. Therefore, the first goal when designing future wireless communication systems (e.g. 4G - fourth generation) has to be the increase in spectral efficiency. The development in digital communications in the past years has enabled efficient modulation and coding techniques for robust and spectral efficient data, speech, audio and video transmission. These are the multi-carrier modulation (e.g. OFDM) and the spread spectrum technique (e.g. DS-CDMA), where OFDM was chosen for broadcast applications (DVB, DAB) as well as for broadband wireless indoor standards (ETSI HIPERLAN-II, IEEE-802.11) and the DS-CDMA was selected in mobile communications (IS-95, third generation mobile radio systems world wide, UMTS/IMT 2000). Since 1993 various combinations of multi-carrier (MC) modulation and the spread spectrum (SS) technique have been introduced and the field of MC-SS communications has become an independent and important research topic with increasing activities. New application fields have been proposed such as high rate cellular mobile, high rate wireless indoor and LMDS. It has been shown that MC-SS offers the high spectral efficiency, robustness and flexibility that is required for the next generation systems. Meanwhile, different alternative hybrid schemes such as OFDM/OFDMA, MC-TDMA, etc. have been deeply analysed and adopted in different international standards (ETSI-BRAN, IEEE-802 & MMAC). Multi-Carrier & Spread-Spectrum: Analysis of Hybrid Air Interfaces draws together all of the above mentioned hybrid schemes therefore providing a greatly needed resource for system engineers, telecommunication designers and researchers in order to enable them to develop, build and deploy several schemes based on MC-transmission for the next generation systems (which will be an integration of broadband multimedia services covering both 4G mobile and fixed wireless systems). * Offers a complete treatment of multi-carrier, spread-spectrum (SS) and time division multiplexing (TDM) techniques * Provides an in-depth insight into hybrid multiple access techniques based on multi-carrier (MC) transmission * Presents numerous hybrid multiple access and air interface architectures including OFDM/CDMA, MC-CDMA, MC-DS-CDMA and MT-CDMA * Covers new techniques such as space-time coding and software radio Telecommunications engineers, hardware & software system designers and researchers as well as students, lecturers and technicians will all find this an invaluable addition to their bookshelf.

Download or read book Space Time Coding for Broadband Wireless Communications written by Georgios B. Giannakis and published by John Wiley & Sons. This book was released on 2007-02-26 with total page 488 pages. Available in PDF, EPUB and Kindle. Book excerpt: Eine vielversprechende Technologie zur Maximierung der Bandbreiteneffizienz in der breitbandigen drahtlosen Kommunikation ist die Raum-Zeit-Kodierung. Theorie und Praxis verbindend, ist dieses Buch die erste umfassende Diskussion von Grundlagen und designorientierten Aspekten von Raum-Zeit-Codes. Single-Carrier und Multi-Carrier-Übertragungen für Einzel- und Mehrnutzerkommunikation werden behandelt.

Download or read book Fundamentals of Wireless Communication written by David Tse and published by Cambridge University Press. This book was released on 2005-05-26 with total page 598 pages. Available in PDF, EPUB and Kindle. Book excerpt: This textbook takes a unified view of the fundamentals of wireless communication and explains cutting-edge concepts in a simple and intuitive way. An abundant supply of exercises make it ideal for graduate courses in electrical and computer engineering and it will also be of great interest to practising engineers.

Download or read book Multi Carrier Spread Spectrum Related Topics written by Khaled Fazel and published by Springer Science & Business Media. This book was released on 2013-03-09 with total page 376 pages. Available in PDF, EPUB and Kindle. Book excerpt: Multi-Carrier Spread-Spectrum has been deeply studied and new alternative solutions have been proposed. This book edits the newest contributions and research results in this new field presented at the Third International Workshop on MC-SS & Related Topics, held in Oberpfaffenhofen, Germany.

Download or read book Antennas and Propagation for Wireless Communication Systems written by Simon R. Saunders and published by John Wiley & Sons. This book was released on 2007-05-07 with total page 547 pages. Available in PDF, EPUB and Kindle. Book excerpt: Antennas and propagation are of fundamental importance to the coverage, capacity and quality of all wireless communication systems. This book provides a solid grounding in antennas and propagation, covering terrestrial and satellite radio systems in both mobile and fixed contexts. Building on the highly successful first edition, this fully updated text features significant new material and brand new exercises and supplementary materials to support course tutors. A vital source of information for practising and aspiring wireless communication engineers as well as for students at postgraduate and senior undergraduate levels, this book provides a fundamental grounding in the principles of antennas and propagation without excessive recourse to mathematics. It also equips the reader with practical prediction techniques for the design and analysis of a very wide range of common wireless communication systems. Including: Overview of the fundamental electromagnetic principles underlying propagation and antennas. Basic concepts of antennas and their application to specific wireless systems. Propagation measurement, modelling and prediction for fixed links, macrocells, microcells, picocells and megacells Narrowband and wideband channel modelling and the effect of the channel on communication system performance. Methods that overcome and transform channel impairments to enhance performance using diversity, adaptive antennas and equalisers. Key second edition updates: New chapters on Antennas for Mobile Systems and Channel Measurements for Mobile Radio Systems. Coverage of new technologies, including MIMO antenna systems, Ultra Wideband (UWB) and the OFDM technology used in Wi-Fi and WiMax systems. Many new propagation models for macrocells, microcells and picocells. Fully revised and expanded end-of-chapter exercises. The Solutions Manual can be requested from www.wiley.com/go/saunders_antennas_2e