Microprocessor-based digital control using delta modulation

Economical digital-based controllers with simple hardware for modern control applications are described. The digital portions of these controllers accept binary delta modulation sequences representing sensor signals and produce binary delta modulation sequences for the controls. These have no more than single-step error, eliminating numerical overflow and the associated problem of limit cycle behavior. The fixed-coefficient, variable delay nature of the controllers defines an important new class of transfer function or state variable synthesis problems.