A Novel Forward-Looking Target Reconstruction Method With Electromagnetic Vortex Interferometry

For the target in the radar forward-looking sight, only the range-history phase information can be exhibited when the plane electromagnetic (EM) wave illuminating. For traditional approaches, the reconstruction of target azimuthal information requires antennas configured at both ends of the long baseline to implement multi-angle observation, usually leading to a baseline length burden. In contrast, the target’s azimuth information, related to the orbital angular momentum (OAM), is directly modulated in the new-dimensional echo phase by the antenna radiating the vortex EM wave, which provides a new foundation for target azimuth reconstruction. In this article, a novel forward-looking target reconstruction methodology with EM vortex interferometry is proposed, and the target 3-D imaging with different OAM modes interferometry strategies is achieved as well. The developed approach can improve the target azimuthal reconstruction error performance without increasing the length of short baseline and image registration. Comprehensive results of simulated data and real-world measured data are performed to validate the effectiveness and anti-noise robustness of the proposals.