Modified Stockwell Transforms and Time-Frequency Analysis

We give results complementary to those in the paper [4] from the perspective of time-frequency analysis [1] to the effect that high frequencies can be amplified and low frequencies diminished. Time-frequency spectra for the chirp, the sum of the cosine functions and the Gaussian-modulated sinusoidal pulse are presented for comparisons, The property of the absolutely referenced phase information of modified Stockwell transforms is given in terms of Riesz transforms.