Coherent integration of quasi-random pulse train based on phased array radar

To improve the performance of phased array radar for the weak object detection, accumulation process is required to be performed over time to gather sufficient energy. For this purpose, the coherent integration algorithm is studied in this paper. First, a quasi-random pulse train echo model is presented, which divides the pulse train into a few sub-pulse-trains (time is uniform within the sub-pulse-train, while nonuniform among sub-pulse-trains). Then, on account of the specific features of this model, two integration algorithms based on fast Fourier transform (FFT) are proposed. The first one is coherent integration algorithm and the second one is associated coherent-noncoherent integration algorithm. Both methods are analyzed in detail. Finally, we apply these two algorithms to the real data of a phased array radar and the result verifies their effectiveness in practical application.