Weighted average frequency algorithm for Hilbert-Huang spectrum and its application to micro-Doppler estimation

For micro-Doppler estimation, an innovative Hilbert-Huang transform (HHT)-based instantaneous frequencies estimator approach designated as weighted average frequency algorithm (WAFA) is proposed in this study. The algorithm is a smoothing of adjacent instantaneous frequencies with a normal rectangular window. After achieving Hilbert-Huang spectrum of the signal, weighted average frequencies and amplitudes are then computed to determine the corresponding point on the time-frequency space, based on which micro-Doppler can be finally estimated. This proposed algorithm of micro-Doppler estimation has been successfully applied to experimental cone and human data.