An Improved Local Stability Criterion for Digital Filters With Interference and Overflow Nonlinearity

This brief presents an improved local stability condition for digital filters with saturation overflow nonlinearities and external interference. This brief analyzes the local stability characteristics of digital filters with zero external interference and achieves the H
_∞
performance level with external interference. The proposed criterion is shown to be an improvement over an existing criterion in the literature. Numerical examples are provided to show the usefulness of the established criterion.