Abstract: A pulse sequence time delay-pulse subpattern extrapolation algorithm is proposed to solve the extraction problem of pulse repetition interval (PRI) linear slide pulse sequences in dense signal environments. The algorithm is based on the radar pulse signal shaping law and the pulse subpattern sequence feature of PRI linear slide type signals. By delaying the overall pulse sequences, and calculating the correlation function peaks, the algorithm is then able to extract the pulse subpattern sequence of PRI slide pulse sequences and whole corresponding PRI linear slide pulse sequences, by extrapolating and searching for the pulse subpattern sequence. Experimental results show the averaged accurate rate of the proposed algorithm to be about 95% when extracting PRI linear slide pulse sequences. The classic algorithm is unable to extract effectively, but using the algorithm proposed here it is possible to automatically extract PRI linear slide pulse sequences with a high accuracy rate.