Issue No.02 - February (1971 vol.20)
R.B. Lackey , IEEE
A simple method is presented which defines Walsh functions in terms of products of Rademacher functions, but which preserves the ordering of the Walsh functions necessary to retain the notion of increasing number of zero crossings, or sequency.
Gray code, Rademacher functions, sequency, square waves, Walsh functions, zero crossings.
R.B. Lackey, D. Meltzer, "A Simplified Definition of Walsh Functions", IEEE Transactions on Computers, vol.20, no. 2, pp. 211-213, February 1971, doi:10.1109/T-C.1971.223214