Download or read book Performance of Full rate Full diversity Space time Codes Under Quantization and Channel Estimation Error written by Zhengwei Jiang and published by . This book was released on 2010 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book High Rate Space Time Code with Linear Decoding Complexity for Multiple Transmitting Antennas written by Amir Laufer and published by . This book was released on 2012 with total page 122 pages. Available in PDF, EPUB and Kindle. Book excerpt: The multipath nature of the wireless channel, results in a superposition of the signals of each path at the receiver. This can lead to either constructive or destructive interference. Strong destructive interference is frequently referred to as deep fade and may result in temporary failure of communication due to the severe drop in the channel's signal-to-noise ratio (SNR). To avoid this situation, signal diversity might be introduced. When having more than one antenna at the transmitter and / or receiver, forming a Multiple-Input Multiple-Output (MIMO) channel, spatial diversity can be employed to overcome the fading problem. Space time block codes (STBC) have been shown to be used well with the MIMO channel. Each type of STBC is designed to optimize a different criteria such as rate and diversity, while other characteristics of the code are its error performance and decoding computational complexity. The Orthogonal STBC (OSTBC) family of codes is known to achieve full diversity as well as very simple implementation of the Maximum Likelihood (ML) decoder. However, it was proven that, with complex symbol constellation one cannot achieve a full rate code when the number of transmitting antennas is larger than two. Quasi OSTBC are codes with full rate but with the penalty of more complex decoding, and in general does not achieve full diversity. In this work, new techniques for OSTBC transmission / decoding are explored, such that a full rate code can be transmitted and decoded with linear complexity. The Row Elimination Method (REM) for OSTBC transmission is introduced, which basically involves the transmission of only part of the original OSTBC codeword, resulting in a full rate code termed Semi-Orthogonal STBC (SSTBC). Novel decoding scheme is presented, such that the SSTBC decoding computational complexity remains linear although the transmitted codeword is not orthogonal anymore. A new OSTBC, that complies with the new scheme's requirements, is presented for any number of transmit antennas. The performance of the new scheme is studied under various settings, such as system with limited feedback and multiple antennas at the receiver. The general decoding techniques presented for STBC, assume perfect channel knowledge at the receiver. It was shown, that the performance of any STBC system is severely degraded due to partial channel state information, results from imperfect channel estimation. To minimize the performance loss, one may lengthen the training sequences used for the channel estimation which, inevitably, results in some rate loss. In addition, complex decoding schemes can be used at the receiver to jointly decode the data while enhancing the channel estimation. It is suggested in this work to apply adaptive techniques to mitigate the performance loss without the penalty of additional rate loss or complex decoding. Namely, the bootstrap algorithm is used to further refine the received signals, resulting in better effective rate and performance in the presence of channel estimation errors. Modified implementations for the bootstrap's weights calculation method are also presented, to improve the convergence rate of the algorithm, as well as to maintain a very low computational burden.

Download or read book Space Time Coding written by Hamid Jafarkhani and published by Cambridge University Press. This book was released on 2005-09-22 with total page 320 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book covers the fundamental principles of space-time coding for wireless communications over multiple-input multiple-output (MIMO) channels, and sets out practical coding methods for achieving the performance improvements predicted by the theory. Starting with background material on wireless communications and the capacity of MIMO channels, the book then reviews design criteria for space-time codes. A detailed treatment of the theory behind space-time block codes then leads on to an in-depth discussion of space-time trellis codes. The book continues with discussion of differential space-time modulation, BLAST and some other space-time processing methods and the final chapter addresses additional topics in space-time coding. The theory and practice sections can be used independently of each other. Written by one of the inventors of space-time block coding, this book is ideal for a graduate student familiar with the basics of digital communications, and for engineers implementing the theory in real systems.

Download or read book MIMO OFDM for LTE WiFi and WiMAX written by Lajos Hanzo and published by John Wiley & Sons. This book was released on 2010-11-01 with total page 708 pages. Available in PDF, EPUB and Kindle. Book excerpt: MIMO-OFDM for LTE, WIFI and WIMAX: Coherent versus Non-Coherent and Cooperative Turbo-Transceivers provides an up-to-date portrayal of wireless transmission based on OFDM techniques augmented with Space-Time Block Codes (STBCs) and Spatial-Division Multiple Access (SDMA). The volume also offers an in-depth treatment of cutting-edge Cooperative Communications. This monograph collates the latest techniques in a number of specific design areas of turbo-detected MIMO-OFDM wireless systems. As a result a wide range of topical subjects are examined, including channel coding and multiuser detection (MUD), with a special emphasis on optimum maximum-likelihood (ML) MUDs, reduced-complexity genetic algorithm aided near-ML MUDs and sphere detection. The benefits of spreading codes as well as joint iterative channel and data estimation are only a few of the radical new features of the book. Also considered are the benefits of turbo and LDPC channel coding, the entire suite of known joint coding and modulation schemes, space-time coding as well as SDM/SDMA MIMOs within the context of various application examples. The book systematically converts the lessons of Shannon's information theory into design principles applicable to practical wireless systems; the depth of discussions increases towards the end of the book. Discusses many state-of-the-art topics important to today's wireless communications engineers. Includes numerous complete system design examples for the industrial practitioner. Offers a detailed portrayal of sphere detection. Based on over twenty years of research into OFDM in the context of various applications, subsequently presenting comprehensive bibliographies.

Download or read book Space Time Coding written by Branka Vucetic and published by John Wiley & Sons. This book was released on 2003-06-02 with total page 340 pages. Available in PDF, EPUB and Kindle. Book excerpt: The capacity of wireless data communications is lagging behind demands due to unsatisfactory performance of the existing wireless networks, such as low data rates, low spectral efficiency and low quality of service. Space-time coding is an effective transmit diversity technique to combat fading in wireless communications. Space-time codes are a highly bandwidth-efficient approach to signalling within wireless communication that takes advantage of the spatial dimension by transmitting a number of data streams using multiple co-located antennas. There are various approaches to the coding structures, including space-time trellis coded modulation, space-time turbo codes and also layered architectures. The central issue in all these various coding structures is the exploitation of multipath effects in order to achieve very high spectral efficiencies. The spectral efficiencies of traditional wireless systems range between 1-5bps/sec/Hz but by using space-time techniques spectral efficiencies of 20-40bps/sec/Hz have been possible. Hence, space-time coding enables an increase in capacity by an order of magnitude. This is the main reason why space-time codes have been included in the standards for the third generation wireless communication systems and ultimately why Space-time Coding will be in great demand by individuals within industry and academia. The comprehensive understanding of space-time coding is essential in the implementation of 3G, and as the only title currently available, Space-Time Coding will be the standard text for Researchers, telecommunication engineers and network planners, academics and undergraduate/postgraduate students, telecommunications managers and consultants.

Download or read book Quasi orthogonal Space time Block Code written by Chau Yuen and published by Imperial College Press. This book was released on 2007 with total page 209 pages. Available in PDF, EPUB and Kindle. Book excerpt: Quasi-Orthogonal Space-Time Block Code presents an up-to-date, comprehensive and in-depth discussion of an important emerging class of space-time codes, called the Quasi-Orthogonal STBC (QO-STBC). Used in Multiple-Input Multiple-Output (MIMO) communication systems, they provide transmit diversity with higher code rates than the well-known orthogonal STBC (O-STBC), yet at lower decoding complexity than non-orthogonal STBC. This book will help readers gain a broad understanding of the fundamental principles as well as the state-of-the-art work in QO-STBC, thus enabling them to appreciate the roles of QO-STBC in future broadband wireless systems and to inspire further research. Sample Chapter(s). Foreword (151 KB). Chapter 1: Introduction of MIMO Channel and Space-Time Block Code (703 KB). Contents: Introduction of MIMO Channel and Space-Time Block Code; Orthogonal and Quasi- Orthogonal Space-Time Block Code; Insights of QO-STBC; Quasi-Orthogonal Space-Time Block Code with Minimum Decoding Complexity; Differential QO-STBC; Rate, Complexity and Diversity Trade-Off in QO-STBC; Other Developments and Applications of QO-STBC. Readership: Academics and graduate-level research students and developers of next-generation wireless systems.

Download or read book Performance Analysis and Design of Space time Codes written by Chen Liao and published by . This book was released on 2006 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Wireless communication technologies have evolved from the original analog networks to IP-based network. Today's wireless communications have been affected by increasing customer expectations on wireless wideband internet services and continuously evolving improvements on technologies. Wireless communication systems must increase their ability to respond to the challenges. The new generation wireless systems (3G/4G) are designed for this purpose. The notable characteristic of 3G/4G is that it provides high data rate transmission at data rate up to 348kbps/2Mbps for 3G and 100Mbps/1Gbps for 4G. Designing the system for such high data rate transmission has become very challenging for wireless systems where the multipath fading is an important factor. In recent years, researches are ongoing in the industry and academic to increase capacity performance of wireless systems through antenna diversity. Multiple Input Multiple Output (MIMO) is one of the major recent developments in the study of high data rate transmission. There has been considerable attention paid to remarkable performance improvements in MIMO in terms of capacity. Another technology that has been traditionally adopted for wireless communications is the channel coding. Combining MIMO with channel coding has received increasing interest to support a variety of high data rate applications. These schemes have been termed as "space-time codes". Space-time codes are currently an area of exciting activity and have been studied as promising candidates for future 3G/4G systems. The most important characteristic of space-time codes is that it can provide full diversity gain as well as coding gain. In this dissertation, both performance analysis of upper bound of Pair-Wise Error Probability (PEP) and exact PEP are performed. In the derivation of exact PEP, a new method is presented. The method is straightforward and comprehensible. The upper bound provides the insight to understand the performance behavior for high Signal-to-Noise Ratio (SNR), while the exact PEP provides a better understanding of the performance behavior to other range of SNR. Design criteria for space-time codes had been first developed by Tarokh, which utilize the analysis of the upper bound on PEP to maximize diversity gain and coding gain from the property of the codeword distance matrix. These criteria are the most widely accepted, which form the basis for space-time codes. The criteria assume that the performance of space-time codes is dominated by the dominant error events. However, there are no dominant error events in fading channel for space-time codes. Therefore, Tarokh's criteria do not provide design guideline for the coding gain. Union bound analysis offers a alternative solution to this problem. The union bound technique is a more attractive method that allows us to analyze the contribution of all error events to the performance. In this thesis, the performance of space-time codes are analyzed using union bound analysis. Based on the union bound on Frame Error Rate (FER), new design criteria are proposed. This is achieved by applying more accurate upper bound of PEP in the union bound analysis. With the proposed criteria, new coding gain performance metrics had been defined. New codes based on the new performance metrics are designed and their coding gain performance superiority are demonstrated. Space-time block codes have been initially designed to provide full diversity order with low decoding complexity, but without coding gain. By integrating space-time trellis codes with space-time block codes, super-orthogonal space-time trellis codes can significantly enhance the coding gain performance. However, the super-orthogonal space-time trellis codes improve performance only in slow fading channel, but do not perform well in fast fading channel. In fast fading channel, the orthogonal design of space-time block codes has little effect on the coding gain and does not lead to noticeable improvement. Furthermore, super-orthogonal space-time trellis codes introduce the diversity gain loss in fast fading channel. It is well known that the performances of space-time codes are dominated by diversity gain and any diversity gain loss may cause substantial loss in performance. We therefore develop orthogonal space-time trellis codes, which improve performance in diversity gain in fast fading channel. The improvement is achieved by transferring the vector output of space-time trellis codes into an orthogonal matrix of space-time block codes, and meanwhile maintaining the symbol Hamming distance of space-time trellis codes. Theoretical analysis and simulation results had demonstrated that the proposed codes can improve diversity gain linearly with an increase in the number of transmit antennas. Performance saturation and decoding complexity increase with the increased number of trellis states are the major problems that trellis-based codes have to face in practice. Turbo codes that allow for reaching near Shannon limit performance are a significant advance in digital communications. Space-time turbo codes have been developed to achieve high performance. In a perfect world, system designers would like to achieve high performance while maintaining a full code rate. Therefore, puncture operation is always used in space-time turbo codes. The problem with the puncture operation in space-time turbo codes is that codeword distance matrix is rank deficient for small diversity gain in slow fading channel, which constitutes a major problem with space-time turbo codes. Space-time turbo codes that concern the rank deficiency have been developed. The codes improve performance by reducing the effect of rank deficiency on performance, but exist high complexity in both code structure and design criteria. This limitation makes the codes not suitable for the design of complex codes with large trellis state and/or large numbers of transmit antennas. A new space-time turbo codes have been proposed in this research. In previous works, it has been demonstrated the systematic structure with the rotation of the output of the low constitute encoder can effectively reduce the rank deficient effect on performance. Our new codes utilize the systematic characteristic to construct a simple code structure. Further, a simple but very effective trace criterion has been proposed. With the simple codes structure and design criteria, the design of complex codes can be achieved with significant improvement in coding gain performance for the systems with small diversity gain in slow fading channel. Overall, this dissertation presents new design criteria and new codes that contribute to improving performances of space-time codes.

Download or read book Space Time Coding for Broadband Wireless Communications written by Georgios B. Giannakis and published by Wiley-Interscience. This book was released on 2006-12-15 with total page 464 pages. Available in PDF, EPUB and Kindle. Book excerpt: This is the first book on space-time coding for wireless communications, one of the most promising techniques for ensuring bandwidth efficiency. The text describes theoretical principles as well as engineering applications; discusses key criteria in the design of practical space-time codes; and covers single-carrier and multi-carrier transmission for both single- and multi-user communications.

Download or read book Space Time Block Coding and Its Application in Wireless Networks written by Yu Chang and published by . This book was released on 2005 with total page 340 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Advances in Mobile and Wireless Communications written by István Frigyes and published by Springer Science & Business Media. This book was released on 2008-05-31 with total page 416 pages. Available in PDF, EPUB and Kindle. Book excerpt: Lectori Salutem! This is another book – among the myriads – dealing with wireless communications. The reader might be aware: this topic is really among bestsellers in technology – bestsellers in technology itself and that in technical literature. Communications is one of the leading techniques in information society and mobile/wireless communications is one among the (maybe not more than two with optics the second) leading techniques in communications. Development of wireless communications was and is really spec- cular in the last decade of the 20th and first decade of the 21st century. Such topics as MIMO, wireless networking, security in the technological field, new business models in the service providing field, various applications in the users’ side, to mention a few only, were undergoing an unprecedented evolution. So it is not surprising that the number of conferences and the number of books in this field grows and grows, in a nearly unbounded way.

Download or read book Doubly selective Channels written by Xiaoli Ma and published by . This book was released on 2003 with total page 394 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Space Time Coding written by Md Anisul Karim and published by . This book was released on 2007 with total page 112 pages. Available in PDF, EPUB and Kindle. Book excerpt:

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 Performance of Cooperative Space Time Coding with Spatially Correlated Fading and Imperfect Channel Estimation written by and published by . This book was released on 2005 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: A performance evaluation of CSTC (Cooperative Space Time Coding) with spatially cor-related fading and imperfect channel estimation in Gaussian as well as impulsive noise is presented. Closed form expressions for the pairwise error probability conditioned on the estimated channel gains are derived by assuming the components of the received vector are independent given the estimated channel gains. An expurgated union bound using the limiting before averaging technique given the estimated channel gains is then obtained. Although this assumption is not strictly valid, simulation results show that the bound is accurate in estimating the diversity order as long the channel estimation is not very poor. It is found that CSTC with block fading channels can reduce the frame error rate (FER) relative to SUSTC (Single User Space Time Coding) with quasi-static fading channels, even when the channel gains for each user are strongly correlated and when the channel estimations are very poor. A decision metric for CSTC with spatially correlated fading, imperfect channel estimation, and impulsive mixture Gaussian noise is derived which yields lower FERs than the Gaussian noise decision metric. Simulation results show that the FER performance of CSTC with mixture Gaussian noise outperforms CSTC with Gaussian noise at low SNR. At high SNR, the FER performance of CSTC with Gaussian noise is better than the FER performance of CSTC with mixture Gaussian noise due to the heavy tail of the mixture Gaussian noise.

Download or read book Space time Codes Concatenated with Turbo Codes Over Fading Channels written by and published by . This book was released on 2004 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The uses of space-time code (STC) and iterative processing have enabled robust communications over fading channels at previously unachievable signal-to-noise ratios. Maintaining desired transmission rate while improving the diversity from STC is challenging, and the performance of the STC suffers considerably due to lack of channel state information (CSI). This dissertation research addresses issues of considerable importance in the design of STC with emphasis on efficient concatenation of channel coding and STC with theoretical bound derivation of the proposed schemes, iterative space-time trellis coding (STTC), and differential space-time codes. First, we concatenate space-time block code (STBC) with turbo code for improving diversity gain as well as coding gain. Proper soft-information sharing is indispensable to the iterative decoding process. We derive the required soft outputs from STBC decoders for passing to outer turbo code. Traditionally, the performance of STBC schemes has been evaluated under perfect channel estimation. For fast time-varying channel, obtaining the CSI is tedious if not impossible. We introduce a scheme of calculating the CSI at the receiver from the received signal without the explicit channel estimation. The encoder of STTC, which is generally decoded using Viterbi like algorithm, is based on a trellis structure. This trellis structure provides an inherent advantage for the STTC scheme that an iterative decoding is feasible with the minimal addition computational complexity. An iteratively decoded space-time trellis coding (ISTTC) is proposed in this dissertation, where the STTC schemes are used as constituent codes of turbo code. Then, the performance upper bound of the proposed ISTTC is derived. Finally, for implementing STBC without channel estimation and maintaining transmission rate, we concatenate differential space-time block codes (DSTBC) with ISTTC. The serial concatenation of DSTBC or STBC with ISTTC offers improving performance, even without an outer channel code. These schemes reduce the system complexity compared to the standalone ISTTC and increase the transmission rate under the same SNR condition. Detailed design procedures of these proposed schemes are analyzed.

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 Dissertation Abstracts International written by and published by . This book was released on 2007 with total page 924 pages. Available in PDF, EPUB and Kindle. Book excerpt: