SFM signal detection and parameter estimation based on pulse-repetition-interval transform

A novel algorithm is proposed for detecting and estimating sinusoidal frequency-modulated (SFM) signals based on the pulse-repetition-interval (PRI) transform which is originally used for estimating PRIs of pulse trains. Our algorithm utilizes the resemblance between the spectrum of a SFM signal and a pulse train, and applies the PRI transform to this spectrum. It can detect SFM signals under moderate signal-to-noise ratios, and is also capable of accurately estimating the modulation frequencies even if there are multiple components. The algorithm proposed has been successfully applied to simulated data, and compared with that of the autocorrelation method, showing its superiority.