Instantaneous Frequency Estimation of Discrete Time Signals

Abstract

The classical concept of instantaneous frequency, obtained by differentiating the instantaneous phase is one of the most used approaches. Nonlinear signals usually have nonlinear and nonstationary behavior. Revealing hidden properties of time discrete signals could be important in understanding specific phenomena or processes. This paper uses simulated signals to prove the utility of instantaneous frequency estimation in dedicated signal processing. The procedure is based on empirical mode decomposition of the signal into monocomponents. The Hilbert transform of these monocomponents reveals they instantaneous frequencies. There are certain mathematical requirements and limitations for signals that the proposed procedure could perform proper instantaneous frequency estimation. The used signals are artificial and the procedure is carried out in MATLAB.

Keywords

• instantaneous frequency
• empirical mode decomposition