Simulation of quadrature-bandpass Sigma-Delta analog to digital converters using state space descriptions

This paper describes an extension to the popular Matlab delta-sigma toolbox. The delta-sigma toolbox is restricted to the generation and simulation of low-pass DeltaSigma analog to digital converters (ADCs). This work enables the toolbox to generate and simulate quadrature bandpass (polyphase) ADCs. After a short introduction and general explanations of DeltaSigma based ADCs, the generation of optimized polyphase loop filters from their lowpass equivalents using the toolbox approach is described. The corresponding sourcecodes for generation and simulations of these ADCs are provided. Demonstration examples with various simulation results are supplied. The toolbox enhancements have been published for download at the Mathworks Matlab internet site.