Chapter 10 - Instantaneous Frequency Estimation and Localization

Abstract

This chapter discusses the instantaneous frequency (IF) estimation and localization. A critical feature of a non-stationary signal is provided by its IF, which accounts for the signal spectral variations as a function of time. This chapter presents methods and algorithms for the localization and estimation of the signal IF. The IF has many applications in time–frequency signal analysis. The IF can also be utilized to obtain distributions mainly concentrated along the IF for monocomponent signals. The first conventional approach for IF estimation used the spectrogram. To account for its window-dependent resolution, improvements were made by introducing iterative methodologies on the estimate provided by the first moment of the spectrogram. Another approach uses an adaptive algorithm for IF estimation using the peak of suitable TFDs with adaptive window length. The method has now been extended to the case of multicomponent signals using the modified B-distribution.