1. n. [Geophysics]

In digital signal processing, a nonsinusoidal transform by addition and subtraction. The Walsh-Hadamard transform is similar to Fourier series analysis, but uses square waves instead of sinusoidal waves. It is used predominantly in communication theory and, to a lesser extent, in filtering logs with a blocky character.

See related terms: filter,  Fourier analysis,  Fourier transform