Overview of Signal Instantaneous Frequency Estimation Methods

This paper gives an overview of existing instantaneous frequency (IF) estimation methods divided into several major categories. One of the first IF estimation approaches was based on the spectrogram, the resolution of which is highly window size dependant. In order to improve the IF estimation accuracy, the iterative method was proposed, such that each iteration gives more accurate estimation of the IF and better timefrequency representation (TFR) of the signal. For the case of the polynomial frequency modulated (FM) signals, several different methods using the polynomial Wigner-Ville distribution (WVD) and higher order ambiguity functions (HAFs) were proposed. The Wigner-Ville spectrum (WVS) was shown to be optimal for linear FM signals in multiplicative noise, while the polynomial WVD was used for high-order polynomial FM signals corrupted by multiplicative noise. Another way to estimate signal’s IF was based on localization of peaks from adaptive lag window TFRs. Various monocomponent IF estimation methods were upgraded and applied to the IF estimation from multicomponent signals. Furthermore, some image processing techniques were applied to the IF localization and estimation from various suitable TFRs.