Look-Ahead Based Sigma-Delta Modulation [Hardcover]

The aim of this book is to expand and improve upon the existing knowledge on discrete-time 1-bit look-ahead sigma-delta modulation in general, and to come to a solution for the above mentioned specific issues arising from 1-bit sigma-delta modulation for SA-CD. In order to achieve this objective an analysis is made of the possibilities for improving the performance of digital noise-shaping look-ahead solutions. On the basis of the insights obtained from the analysis, several novel generic 1-bit look-ahead solutions that improve upon the state-of-the-art will be derived and their performance will be evaluated and compared. Finally, all the insights are combined with the knowledge of the SA-CD lossless data compression algorithm to come to a specifically for SA-CD optimized look-ahead design.1. Introduction.- 2. Basics of sigma-delta modulation.- 3. Transient SDM performance.- 4. Noise-shaping quantizer model.- 5. Look-ahead sigma-delta modulation.- 6. Reducing the complexity of LA DD conversion.- 7. Trellis sigma-delta modulation.- 8. Efficient Trellis sigma-delta modulation.- 9. Pruned Tree sigma-delta modulation.- 10. Pruned Tree sigma-delta modulation for SA-CD.- 11. Comparison of look-ahead SDM techniques.- 12. Maximum SNR analysis.- 13. General Conclusions.- Appendix A: FFT calculations - coherent and power averaging.- Appendix B: Descriptions of the used Sigma-Delta Modulators.
High resolution analog-to-digital conversion and digital-to-analog conversion is often realized with the use of a Sigma-Delta Modulator (SDM). The sigma-delta modulation process, although very non-linear when a 1-bit quantizer is used, is nowadays well understood and can be made to deliver a very high signal conversion quality. An example system that pushes the traditional sigma-delta modulation algorithm to its performance limit is the Super Audio CD (SA-CD) standard, in which a 64 times oversampled 1-bit signal is used to represent audio content with an SNR of up to 120~dB ovel