Comments on "The Modulo Time Plot: A Useful Data Acquisition Diagnostic Tool"

In a paper by S. Renaud "Algorithm unrolls spectra" (1988), the use of a reordered sample set is very useful for quick visual inspection of system performance. The artificial oversampling algorithm unrolls spectra. However, the question is how to reorder the samples. To answer that, one must recall the conditions for uniform permutation of samples (see S.C. Kak et al. (1977) and D.L. Duttweiler et al. (1978)). Signal sampling and quantising procedures are analysed and it is suggested that the technique of the uniform permutation can be used for other desirable waveform or spectrum modifications.