A Radar Detection Method of Reentry Target Based on Frequency-Domain Processing

When the reentry target passes through the earth’s atmosphere, its surface is covered with a layer of plasma sheath. In the process of radar detection of the reentry target, the echo signal will couple with multi-Doppler frequency components and form multiple mismatch effects with matched filter, which will produce false targets on the 1-D range profile. Meanwhile, the excessive speed of the reentry target will lead to the phenomenon of migration through range cells (MTRCs), which will further affect the detection and recognition of the target. This article proposes an improved frequency-domain compensation method that aims at false target and cross-range unit migration. By constructing the intrapulse Doppler frequency and interpulse Doppler frequency compensation functions, the multiperiod echo signal is processed to eliminate the MTRC phenomenon and improve the energy gain of the real target. Finally, the feasibility of the proposed algorithm is verified by simulation, which lays a theoretical foundation for the effective detection and reliable tracking of plasma-sheath-covered targets.