Multi‐component instantaneous frequency estimation using locally adaptive directional time frequency distributions

Summary This paper presents a locally adaptive time‐frequency ( t , f ) method for estimating the instantaneous frequency (IF) of multi‐component signals. A high‐resolution adaptive directional time‐frequency distribution (ADTFD) is defined by locally adapting the direction of its smoothing kernel at each ( t , f ) point based on the direction of the energy distribution in the ( t , f ) domain. The IF of signal components is then estimated from the ADTFD using an image processing algorithm. Using the mean square error between the original IF and estimated IF as a performance criterion, experimental results indicate that the ADTFD gives better IF estimation performance compared with other TFDs for a multi‐component signal. For example, for signal‐to‐noise ratio of 12dB, the IF estimate obtained using the ADTFD achieves a mean square error of −42dB for a weak signal component, which is an improvement of −12dB compared with other TFDs.