Author: Nitin Ashok Nangare Publisher: ISBN: Category : Languages : en Pages :
Book Description
A non-iterative receiver is proposed to achieve near capacity performance on intersymbol interference (ISI) channels. There are two main ingredients in the proposed design. i) The use of a novel BCJR-DFE equalizer which produces optimal soft estimates of the inputs to the ISI channel given all the observations from the channel and L past symbols exactly, where L is the memory of the ISI channel. ii) The use of an encoder structure that ensures that L past symbols can be used in the DFE in an error free manner through the use of a capacity achieving code for a memoryless channel. Computational complexity of the proposed receiver structure is less than that of o̲n̲e̲ iteration of the turbo receiver. We also provide the proof showing that the proposed receiver achieves the i.i.d. capacity of any constrained input ISI channel. This DFE-based receiver has several advantages over an iterative (turbo) receiver, such as low complexity, the fact that codes that are optimized for memoryless channels can be used with channels with memory, and finally that the channel does not need to be known at the transmitter. The proposed coding scheme is universal in the sense that a single code of rate r; optimized for a memoryless channel, provides small error probability uniformly across all AWGN-ISI channels of i.i.d. capacity less than r. This general principle of a proposed non-iterative receiver also applies to other signal processing functions, such as timing recovery, pattern-dependent noise whitening, joint demodulation and decoding etc. This makes the proposed encoder and receiver structure a viable alternative to iterative signal processing. The results show significant complexity reduction and performance gain for the case of timing recovery and patter-dependent noise whitening for magnetic recording channels.
Author: Keith Chugg Publisher: Springer Science & Business Media ISBN: 1461516994 Category : Technology & Engineering Languages : en Pages : 381
Book Description
Iterative Detection: Adaptivity, Complexity Reduction, and Applications is a primary resource for both researchers and teachers in the field of communication. Unlike other books in the area, it presents a general view of iterative detection that does not rely heavily on coding theory or graph theory. The features of the text include: Both theoretical background and numerous real-world applications. Over 70 detailed examples, 100 problems, 180 illustrations, tables of notation and acronyms, and an extensive bibliography and subject index. A whole chapter devoted to a case study on turbo decoder design. Receiver design guidelines, rules and suggestions. The most advanced view of iterative (turbo) detection based only on block diagrams and standard detection and estimation theory. Development of adaptive iterative detection theory. Application of adaptive iterative detection to phase and channel tracking in turbo coded systems and systems representative of digital mobile radio designs. An entire chapter dedicated to complexity reduction. Numerous recent research results. Discussion of open problems at the end of each chapter. Among the applications considered in this book are joint equalization and decoding, turbo codes, multiuser detection and decoding, broadband wireless channel equalization, and applications to two-dimensional storage and imaging systems. Audience: Iterative Detection: Adaptivity, Complexity Reduction, and Applications provides an accessible and detailed reference for researchers, practicing engineers, and students working in the field of detection and estimation. It will be of particular interest to those who would like to learn how iterative detection can be applied to equalization, interference mitigation, and general signal processing tasks. Researchers and practicing engineers interested in learning the turbo decoding algorithm should also have this book.
Author: Norbert Goertz Publisher: Imperial College Press ISBN: 1860948464 Category : Technology & Engineering Languages : en Pages : 207
Book Description
This book provides the first comprehensive and easy-to-read discussion of joint source-channel encoding and decoding for source signals with continuous amplitudes. It is a state-of-the-art presentation of this exciting, thriving field of research, making pioneering contributions to the new concept of source-adaptive modulation. The book starts with the basic theory and the motivation for a joint realization of source and channel coding. Specialized chapters deal with practically relevant scenarios such as iterative source-channel decoding and its optimization for a given encoder, and also improved encoder designs by channel-adaptive quantization or source-adaptive modulation. Although Information Theory is not the main topic of the book OCo in fact, the concept of joint source-channel coding is contradictory to the classical system design motivated by a questionable practical interpretation of the separation theorem OCo this theory still provides the ultimate performance limits for any practical system, whether it uses joint source-channel coding or not. Therefore, the theoretical limits are presented in a self-contained appendix, which is a useful reference also for those not directly interested in the main topic of this book. Sample Chapter(s). Chapter 1: Introduction (98 KB). Contents: Joint Source-Channel Coding: An Overview; Joint Source-Channel Decoding; Channel-Adaptive Scaled Vector Quantization; Index Assignments for Multiple Descriptions Vector Quantizers; Source-Adaptive Modulation; Source-Adaptive Power Allocation; Appendices: Theoretical Performance Limits; Optimal Decoder for a Given Encoder; Symbol Error Probabilities for M-PSK; Derivative of the Expected Distortion for SAM. Readership: Students at advanced undergraduate and graduate level; practitioners and academics in Electrical and Communications Engineering, Information Technology and Computer Science."
Author: Tadeusz Wysocki Publisher: Springer Science & Business Media ISBN: 0306477912 Category : Science Languages : en Pages : 294
Book Description
Advanced Signal Processing for Communication Systems consists of 20 contributions from researchers and experts. The first group of chapters deals with the audio and video processing for communications applications, including topics ranging from multimedia content delivery over the Internet, through the speech processing and recognition to recognition of non-speech sounds that can be attributed to the surrounding environment. The book also includes sections on applications of error control coding, information theory, and digital signal processing for communication systems like modulation, software-defined radio, and channel estimation. Advanced Signal Processing for Communication Systems is written for researchers working on communication systems and signal processing, as well as telecommunications industry professionals.
Author: Ernesto Damiani Publisher: Springer Science & Business Media ISBN: 0387725008 Category : Technology & Engineering Languages : en Pages : 334
Book Description
This is an edited volume, written by well-recognized international researchers with extended chapter style versions of the best papers presented at the SITIS 2006 International Conference. This book presents the state-of-the-art and recent research results on the application of advanced signal processing techniques for improving the value of image and video data. It introduces new results on video coding on time-honored topic of securing image information. The book is designed for a professional audience composed of practitioners and researchers in industry. This book is also suitable for advanced-level students in computer science.
Author: Søren Hein Publisher: Springer Science & Business Media ISBN: 9780792393092 Category : Computers Languages : en Pages : 274
Book Description
Analog-to-digital (A/D) converters are key components in digital signal processing (DSP) systems and are therefore receiving much attention as DSP becomes increasingly prevalent in telephony, audio, video, consumer products, etc. The varying demands on conversion rate, resolution and other characteristics have inspired a large number of competing A/D conversion techniques. Sigma Delta Modulators: Nonlinear Decoding Algorithms and Stability Analysis is concerned with the particular class of A/D techniques called oversampled noise-shaping (ONS) that has recently come into prominence for a number of applications. The popularity of ONS converters is due to their ease of implementation and robustness to circuit imperfectors. An ONS converter consists of an encoder that generates a high-rate, low-resolution digital signal, and a decoder that produces a low-rate, high-resolution digital approximation to the analog encoder input. The conventional decoding approach is based on linear filtering. Sigma Delta Modulators presents the optimal design of an ONS decoder for a given encoder. It is shown that nonlinear decoding can achieve gains in signaling ratio and the encoder architecture. The book then addresses the instability problem that plagues higher-order ONS encoders. A new stability concept is introduced that is well-suited to ONS encoders, and it is applied to the double-loop encoder as well as to the class of interpolative encoders. It is shown that there exists a trade-off between stability and SNR performance. Based on the results, explicit design examples are presented. Sigma Delta Modulators: Nonlinear Decoding Algorithms and Stability Analysis is a valuable reference source for researchers and engineers in industry and academia working on or interested in design and analysis of A/D converters, particularly to those working in quantization theory and signal reconstruction, and can serve as a text for advanced courses on the subjects treated.
Author: Tülay Adali Publisher: John Wiley & Sons ISBN: 0470575743 Category : Science Languages : en Pages : 428
Book Description
Leading experts present the latest research results in adaptive signal processing Recent developments in signal processing have made it clear that significant performance gains can be achieved beyond those achievable using standard adaptive filtering approaches. Adaptive Signal Processing presents the next generation of algorithms that will produce these desired results, with an emphasis on important applications and theoretical advancements. This highly unique resource brings together leading authorities in the field writing on the key topics of significance, each at the cutting edge of its own area of specialty. It begins by addressing the problem of optimization in the complex domain, fully developing a framework that enables taking full advantage of the power of complex-valued processing. Then, the challenges of multichannel processing of complex-valued signals are explored. This comprehensive volume goes on to cover Turbo processing, tracking in the subspace domain, nonlinear sequential state estimation, and speech-bandwidth extension. Examines the seven most important topics in adaptive filtering that will define the next-generation adaptive filtering solutions Introduces the powerful adaptive signal processing methods developed within the last ten years to account for the characteristics of real-life data: non-Gaussianity, non-circularity, non-stationarity, and non-linearity Features self-contained chapters, numerous examples to clarify concepts, and end-of-chapter problems to reinforce understanding of the material Contains contributions from acknowledged leaders in the field Adaptive Signal Processing is an invaluable tool for graduate students, researchers, and practitioners working in the areas of signal processing, communications, controls, radar, sonar, and biomedical engineering.
Author: Malis̆a Marijan Publisher: ISBN: Category : Languages : en Pages : 101
Book Description
"Delta-sigma A/D conversion is a popular technique used to achieve high resolution data conversion for low to moderate bandwidth applications. By sampling the analog signal at rates much higher than the Nyquist rate, the [delta sigma] A/D converters move most of the signal processing into the digital domain, which makes them less susceptible to analog component non-idealities. It is commonly accepted that the digital circuitry of the [delta sigma] A/D converters should perform a linear time-invariant filtering on the output of the [delta sigma] modulator in order to reconstruct the original signal. However, when the [delta sigma] converters are operated in conjunction with modulation sequences, such as in the parallel [delta sigma] ([pi delta sigma]) converters for high bandwidth applications, the signal reconstruction process becomes time-dependent. In this case, there is no general decoding strategy available for arbitrary numbers of parallel converters and types of modulation sequences. On the other hand, when [delta sigma] converters are operated at higher oversampling ratios (OSRs), the non-linear effects of the [delta sigma] modulators become more emphasized. At higher OSRs and orders of [delta sigma] modulators, non-linear reconstruction algorithms become more beneficial over linear decoding methods. In this work, we study time-varying and non-linear properties of [delta sigma] converters and develop two randomized iterative reconstruction algorithms. First, we design an iterative message passing algorithm on factor graphs for decoding [pi delta sigma] modulators. This approach allows the use of an arbitrary number of parallel paths and different types of modulation sequences, i.e., modulation with pseudo-random sequences. We demonstrate that [pi delta sigma] converters with random modulation sequences produce a spurious-free dynamic range. Second, we show that for higher OSR values, the non-linear reconstruction process can be seen as a linear feasibility problem (LFP). We describe how the LFP can be transformed in a well-conditioned problem and demonstrate the reconstruction process by using the surrogate constraint algorithm which employs random constraint selection. The new algorithm considers a small number of constraints at a time which makes it well suited for implementation on a single-processor unit"--Page v-vi.
Author: Lajos Hanzo Publisher: John Wiley & Sons ISBN: 1119973007 Category : Technology & Engineering Languages : en Pages : 518
Book Description
Recent developments such as the invention of powerful turbo-decoding and irregular designs, together with the increase in the number of potential applications to multimedia signal compression, have increased the importance of variable length coding (VLC). Providing insights into the very latest research, the authors examine the design of diverse near-capacity VLC codes in the context of wireless telecommunications. The book commences with an introduction to Information Theory, followed by a discussion of Regular as well as Irregular Variable Length Coding and their applications in joint source and channel coding. Near-capacity designs are created using Extrinsic Information Transfer (EXIT) chart analysis. The latest techniques are discussed, outlining radical concepts such as Genetic Algorithm (GA) aided construction of diverse VLC codes. The book concludes with two chapters on VLC-based space-time transceivers as well as on frequency-hopping assisted schemes, followed by suggestions for future work on the topic. Surveys the historic evolution and development of VLCs Discusses the very latest research into VLC codes Introduces the novel concept of Irregular VLCs and their application in joint-source and channel coding
Author: Nitin Ashok Nangare
Author: Keith Chugg
Author: Norbert Goertz
Author: Tadeusz Wysocki
Author: Ernesto Damiani
Author: Jinho Choi
Author: Søren Hein
Author: Tülay Adali
Author: Malis̆a Marijan
Author: Lajos Hanzo