A Fast Implementation Method of Stepped-RFT for Motion Parameter Estimation of High-Velocity Weak Target Using Synthetic-Wideband Radar

The synthetic-wideband radars are widely applied no matter in military or civilian fields due to the lower hardware cost and better anti-jamming performance compared with instantaneous wideband systems. However, the performance of synthetic-wideband radars in motion parameter estimation of the high-velocity weak target is severely limited by the inter-pulse non-coherence and decrease of unambiguous velocity range caused by inter-pulse carrier frequency hopping. The lately proposed Stepped-RFT method solves these problems adequately but with high computation complexity. In pursuit of better real-time processing performance, a fast implementation method of the standard Stepped-RFT is proposed by using the idea of fast Chirp-Z transform in this paper. The proposed method can significantly reduce the computation complexity of Stepped-RFT without integration loss by using fast Fourier transform operations instead of two-dimensional joint search operation in range-velocity domain. And Monte Carlo simulation results are given to demonstrate both the coherent integration and parameter estimation performance of the fast implementation method.