In electronic support (ES) systems, the recognition of PRI (pulse repetition interval) for a radar pulse signal has received a lot of attention because of the identification ambiguity in dense electronic warfare signal environments. In this paper, we propose an improved method to recognize PRI modulation type of radar signal at ES (electronic support) in electronic signal environment. The proposed method classifies 4 types of PRIs such as constant PRI, jitter PRI, stagger PRI and sliding PRI using changing value of DPRI and statistics of PRI. The method is applied to simulated data. The result shows that the proposed method correctly identifies various PRI signals.

pulse repetition interval, electronic support, TOA.