A Fast and Real-time PRI Transform Algorithm for Deinterleaving Large PRI Jitter Signals

Abstract

The Pulse Repetition Interval (PRI for short hereafter) is a key parameter in the anti-radiation radar signal sorting in the typical missile detection and guidance tasks. The PRI transform algorithm can overcome the harmonic problem in traditional histogram statistic algorithm, which has a high PRI estimation accuracy. But for pulse flow with unfixed PRI, the Time Difference Of Arrival (TDOA) falling into the same pulse PRI bins has no stable phase relationship, thus it's hard to make an effective accumulation. In order to effectively deinterleaving the PRI jittered signals, the classic way is to overlapping PRI bins and the shifting time origins can be adopted based on classical PRI transform algorithm. However the algorithm has a large amount of operation and became too slow to meet the requirements of real-time in target detection and signal deinterleaving. The principle of PRI transform algorithm is re-analyzed in the paper, and an improved PRI transform algorithm is proposed, where a so-called look-up table approach is introduced as well as the overlapping PRI bins and the shifting time origins. The simulation results showed that the PRI transform algorithm based on Look-up table method can well deinterleave the PRI jittered signals with jitter quantity within 30%, with a considerable estimation precision and performance compared with the traditional PRI transform algorithm. Moreover, the algorithm suggested can accelerate the operation speed significantly and can meet the requirements of real-time in signal sorting. The results in this paper is of practical value which can be adopted in a lot of missile detection and guidance tasks.