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OverviewSigma delta modulation has become a very useful and widely applied technique for high performance Analog-to-Digital (A/D) conversion of narrow band signals. Through the use of oversampling and negative feedback, the quantization errors of a coarse quantizer are suppressed in a narrow signal band in the output of the modulator. Bandpass sigma delta modulation is well suited for A/D conversion of narrow band signals modulated on a carrier, as occurs in communication systems such as AM/FM receivers and mobile phones. Due to the nonlinearity of the quantizer in the feedback loop, a sigma delta modulator may exhibit input signal dependent stability properties. The same combination of the nonlinearity and the feedback loop complicates the stability analysis. In Bandpass Sigma Delta Modulators, the describing function method is used to analyze the stability of the sigma delta modulator. The linear gain model commonly used for the quantizer fails to predict small signal stability properties and idle patterns accurately. In Bandpass Sigma Delta Modulators an improved model for the quantizer is introduced, extending the linear gain model with a phase shift. Analysis shows that the phase shift of a sampled quantizer is in fact a phase uncertainty. Stability analysis of sigma delta modulators using the extended model allows accurate prediction of idle patterns and calculation of small-signal stability boundaries for loop filter parameters. A simplified rule of thumb is derived and applied to bandpass sigma delta modulators. The stability properties have a considerable impact on the design of single-loop, one-bit, high-order continuous-time bandpass sigma delta modulators. The continuous-time bandpass loop filter structure should have sufficient degrees of freedom to implement the desired (small-signal stable) sigma delta modulator behavior. Bandpass Sigma Delta Modulators will be of interest to practicing engineers and researchers in the areas of mixed-signal and analog integrated circuit design. Full Product DetailsAuthor: Jurgen van Engelen , Rudy J. van de PlasschePublisher: Springer-Verlag New York Inc. Imprint: Springer-Verlag New York Inc. Edition: Softcover reprint of hardcover 1st ed. 2000 Dimensions: Width: 15.50cm , Height: 1.10cm , Length: 23.50cm Weight: 0.454kg ISBN: 9781441951168ISBN 10: 1441951164 Pages: 188 Publication Date: 06 December 2010 Audience: Professional and scholarly , Professional & Vocational Format: Paperback Publisher's Status: Active Availability: Out of stock The supplier is temporarily out of stock of this item. It will be ordered for you on backorder and shipped when it becomes available. Table of Contents1 Introduction.- 2 Quantization and Sampling.- 3 Noise Shaping Concepts.- 4 Performance.- 5 Stability.- 6 Design of Continuous time Bandpass SDMs.- 7 SDM Implementations.- 8 Conclusion and Discussion.- References.- List of Acronyms.- List of Symbols.- A Modulator Response to Input Signals.- B Root Locus Search Method.- C Algorithm for Finding a Stability Boundary.- D Example VHDL description of a digital SDM.- About the Authors.ReviewsAuthor InformationTab Content 6Author Website:Countries AvailableAll regions |