An Efficient Approach for Coherent Integration Detection of High-Speed Maneuvering Targets With Arbitrary-Order Doppler Frequency Migrations

In radar detection applications, high-speed maneuvering targets (HSMTs) are commonly encountered. Given the range cell migration (RCM) and arbitrary-order Doppler frequency migrations (DFMs) induced by the complex relative motions between the HSMT and radar, they usually present a great challenge for target detection. In addition, the complex Doppler ambiguity will further aggravate the difficulty in focusing on HSMT. To address these issues, an efficient approach for coherent integration detection of HSMTs is proposed. First, inspired by the symmetrical feature of range frequency, a new range frequency reversal transform is introduced to correct complex arbitrary-order DFMs simultaneously. After that, by exploiting the advantage of range-azimuth joint processing, a modified two-dimensional scaled Fourier transform is developed to remove the residual RCM, and a well-focused result is thus achieved. Furthermore, a discrimination procedure is proposed to remove the spurious peak for cross terms of targets with the same parameters. The proposed method has an extremely low computational cost and does not need to know the target motion order a priori because the operations of multidimensional search and parameter estimation are avoided. It also handles complex arbitrary-order DFMs, blind speed sidelobe, and complex Doppler center blur and spectrum ambiguity. The experiments using real data also validate the performance of the proposed method.