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OverviewAnalog-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 imperfections. 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 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 signal-to-noise ratio (SNR) over linear decoding, depending on the oversampling 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 oversampled analog-to-digital conversion. It is also of interest to those working in quantization theory and signal reconstruction, and can serve as a text for advanced courses on the subjects treated. Full Product DetailsAuthor: Søren Hein , Avideh ZakhorPublisher: Springer Imprint: Springer Edition: 1993 ed. Volume: 213 Dimensions: Width: 15.50cm , Height: 1.50cm , Length: 23.50cm Weight: 1.220kg ISBN: 9780792393092ISBN 10: 0792393090 Pages: 252 Publication Date: 31 January 1993 Audience: College/higher education , Professional and scholarly , General/trade , Postgraduate, Research & Scholarly , Professional & Vocational Format: Hardback Publisher's Status: Active Availability: In Print This item will be ordered in for you from one of our suppliers. Upon receipt, we will promptly dispatch it out to you. For in store availability, please contact us. Table of Contents1 Introduction.- 1.1 Analog-to-Digital Conversion.- 1.2 Conventional Conversion.- 1.3 Oversampled Noise-Shaping Conversion.- 1.4 Contributions and Outline of Work.- 2 Properties of ONS Converters with Constant Inputs.- 2.1 Introduction.- 2.2 Single-Loop Encoder.- 2.3 Double-Loop Encoder.- 2.4 A Modified Cascade Structure for Constant Inputs.- 2.5 Summary.- 3 Optimal Decoding for ONS Encoders with Constant Inputs.- 3.1 Introduction.- 3.2 Optimal Decoding under Ideal Conditions.- 3.3 Decoding in the Presence of Non-Idealities.- 3.4 Summary.- 4 An SVD-Based Method for Band-Limiting Finite Extent Signals.- 4.1 Introduction.- 4.2 SVD-Based Band Limitation.- 4.3 Implementation of the SVD.- 4.4 Computational Properties of Band Limitation Methods.- 4.5 Results.- 4.6 Summary.- 5 Optimal Decoding for ONS Decoders with Band-Limited Inputs.- 5.1 Introduction.- 5.2 Reconstruction Algorithm.- 5.3 Results.- 5.4 Decoding in the Presence of Non-Idealities.- 5.5 Summary.- 6 Halftone to Continuous-Tone Conversion of Error-Diffusion Coded Images.- 6.1 Introduction.- 6.2 Error Diffusion Coding.- 6.3 Decoding Algorithm.- 6.4 Results.- 6.5 Summary.- 7 Stability of ONS Encoders.- 7.1 Introduction.- 7.2 Framework for Stability Analysis.- 7.3 Double-Loop Encoder.- 7.4 Interpolative Encoder.- 7.5 Summary.- 8 Conclusions.- 8.1 Summary.- 8.2 Extensions.- 8.3 Future Directions.- A Appendix to Chapter 2.- A.1 Derivations for Single-Loop Encoder.- A.2 Derivations for Double-Loop Encoder.- A.3 Proofs of Theorems.- B Appendix to Chapter 3.- B.1 Performance Measures.- B.2 Only Codewords Yield Compatible Bounds.- B.3 Form of Non-Idealities.- C Appendix to Chapter 4.- C.1 Energy Concentration.- C.2 Resolution of the DFT.- C.3 Effect of Windowing.- D Appendix to Chapter 5.- D.1 Quadratic Programming Approximation.- E Appendix to Chapter 6.- E.1 Stability of Error Diffusion Encoders.- E.2 Two-Dimensional SVD Band Limitation.- F Appendix to Chapter 7.- F.1 Upper Bounds on Double-Loop Limit Cycles.- F.2 Design of Double-Loop Encoder.- F.3 Describing Function Method.- F.4 Proofs of Statements in Section 7.5.2.2.ReviewsAuthor InformationTab Content 6Author Website:Countries AvailableAll regions |