Digital compression of analytic signals using Nth root

The computation of the Nth root produces a compression of the spectrum for some types of analytic signals. Once the spectrum has been shrinked in the frequency domain, the signal can be decimated in the time domain, leading to compression. The Nth root calculation raises some problems which are discussed, like phase jumps related with zero crossings of the amplitude. Results of simulations with sinusoids and speech signals are reported. More work is needed to make the approach practical.