A coherent detection algorithm for the high-speed targets based on radon inverse fourier transform

Abstract

Within the long-time coherent integration (CI) in radar detection, high-speed targets generally suffer from the range walk (RW) effect, which leads to the typical coherent detection failure. To acquire robust coherent detection, this paper proposes Radon inverse Fourier transform (RIFT). In this paper, we focus on the fact in fast frequency-slow frequency domain that the echo of the target is characterized as a unique straight line whose location simply corresponds to the velocity. Benefiting from this fact, the velocity can be estimated through velocity searching via RIFT, in which the inverse Fourier transform (IFT) is exploited along the velocity-related straight line. Then, we can conduct the CI employing RIFT with the estimated velocity. In comparison with keystone transform (KT) and Radon-Fourier transform (RFT), the advantages of RIFT are as follows: low computational complexity, no interpolation loss as well as the blind speed sidelobe (BSSL) simultaneously. Numerical results demonstrate the effectiveness and the efficiency of the proposed RIFT. Specifically, the proposed algorithm yields 2dB better antinoise performance than scaled inverse Fourier transform (SCIFT) and frequency-domain deramp-keystone transform (FDDKT) in the high-speed target detections.