Abstract: High-accuracy pulse repetition interval (PRI) estimation is meaningful for enhancing the emitter-identification abilities of modern electronic intelligence (ELINT) systems. The maximum-likelihood estimate (MLE) of PRI can be obtained by locating the peak of periodogram of a point process signal used to model the sequence of the time-of-arrival (TOA) measurements. In this paper, a novel two-step numerical search strategy is proposed to search the peak of the periodogram to ensure maximum-likelihood estimation. Simulation results show that our algorithm outperforms the existing methods, especially under the condition of low signal-to-noise ratio (SNR) or high pulse-missing-rate.

Key words: Radar, Pulse repetition interval, Maximum likelihood estimation, Periodic point process, Period estimation