Coherent Integration Method of High-Speed Target for Frequency Agile Radar

In order to detect the high-speed target for frequency agile (FA) radar, a coherent integration method is proposed in this paper. Making full use of the characteristics of the FA radar, the echoes are classified after pulse compression according to carrier frequency and then processed separately. For echoes of the same carrier frequency, keystone transform is applied to correct the range migration and Doppler frequency ambiguity, due to high speed, is compensated based on radon transform. Then, the ambiguous velocity for different carrier frequencies is adjusted to be the same by phase compensation, and the coherent integration is achieved by chirp-z transform for echoes of the same carrier frequency. After carrier frequency rearrangement, a frequency-velocity plane is constructed, and the target's energy is further accumulated by inverse Fourier transform during frequency. Simulation results validate the effectiveness of the proposed method for a high-speed target; meanwhile, the good performances of the proposed method on detection probability, estimation accuracy, and computational efficiency are shown by comparisons with three other methods.