Ship Attitude-Assisted 3-D ISAR Imaging with Non-Ideal UAV-Borne Radar Array

Unmanned aerial vehicle (UA V)-mounted radar systems offer advantages such as proximity observation, flexible viewing angles, and low cost. Combining UA V-mounted radar arrays with inverse synthetic aperture radar (ISAR) imaging technology for 3-D imaging is significant for the classification and identification of ship targets. However, the radar array on the UA V may experience position errors due to external environmental interference or vibrations of the UA V platform. Additionally, ship targets on the sea surface are easily affected by sea conditions and exhibit complex three-dimensional (3-D) swaying motions, which pose challenges to array ISAR 3-D imaging. To address the difficult issue of ship attitude changes and array position errors affecting the quality of ship array ISAR 3-D imaging, this paper introduces a ship attitude-assisted 3-D ISAR imaging approach for non-ideal UA V-mounted radar arrays. The method selects the UA V array configuration based on the ship's attitude (UAC-SAA) and integrates super-resolution direction-of-arrival (DOA) estimation with array element position error compensation (SRD-PECA) to achieve accurate angle measurement results while estimating errors. Combined with ISAR imaging, it realizes high-resolution 3-D imaging of ships with attitude changes.