Haar spectra-based entropy approach to quasi-minimisation of FBDDs

An information theoretic approach, to exploit the additional degree of freedom associated with don´t cares of incompletely specified Boolean functions, is applied to quasi-minimisation of free binary decision diagrams (FBDDs). The concept of entropy and equivocation is formulated through paired Haar spectra of incompletely specified Boolean functions. The likelihood metric expressed in terms of selected spectral coefficients is used to simplify the process of don´t care allocation. The approach is general and can be extended to other combinatorial decision problems