Efficient spectral method of identification of linear Boolean function

This paper discusses a problem of recognition of the Boolean function's linearity. The article describes the spectral method of analysis of incompletely specified Boolean functions using the Walsh Transform. The linearity and nonlinearity play an important role in design of digital circuits. The analysis of the spectral coefficients' distribution allows to determine the various combinatorial properties of the Boolean functions: redundancy, monotonicity, self-duality, correcting capability, etc. which seems to be more difficult to obtain by means of other methods. In particular, the distribution of spectral coefficients allows us to determine whether Boolean function is linear. The method described in the paper can be easily used in investigations of large Boolean functions (of many variables), what seems to be very attractive for modern digital technologies. Experimental results demonstrate the efficiency of the approach.