Nonstationary waveform analysis and synthesis using generalized harmonic analysis

This article presents a new method of spectrum analysis for nonstationary signals, the generalized harmonic analysis (GHA) method. The short-time Fourier transform suffers from truncation effects in spectrum analysis; however, GHA using almost-periodic functions can analyze and synthesize signals without the truncation effects. We have applied GHA to nonstationary signals, such as a piano tone and a singing voice, and found that the time-varying spectra, as well as the pitch, can be visualized with high frequency resolution