Hop Period Estimation for Frequency Hopping Signals Based on Hilbert-Huang Transform

A method for estimating the hop period of frequency hopping (FH) signals based on Hilbert-Huang transform (HHT) is proposed. This method iteratively decomposes the FH signal into intrinsic mode functions (IMFs) and applies Hilbert transform to each IMF to yield Hilbert spectrum, whose maxima for each time instant are extracted to form a sequence. A simple Fourier transform based analysis of the obtained sequence provides the estimate of hop period for a FH signal. The proposed method is fully cross-term free, and it does not make any assumption about the parameter information. The performance of the method is evaluated in terms of estimation variances in the presence of Gaussian white noise.