Fast Transformations with Walsh-Hadamard Functions

Abstract

<p>In this thesis, various techniques to generate Walsh-Hadamard functions are discussed. Efficient algorithms to compute the discrete Walsh-Hadamard transform have been derived and implemented. The design of a simple, but very fast, digital circuit that can perform the transform or its inverse is presented. These algorithms have been applied to the processing of speech for the investigation of bit rate reduction. Intelligible speech has been reconstructed from 8 or 4 dominant Walsh-Hadamard coefficients out of a field of 64, with a constant update time of 8 milliseconds, on a CDC-1700 computer.</p>