SAR Jamming via Metasurface-Enabled Spatial-Block Subsection Shift-Frequency Modulation

Synthetic aperture radar (SAR) imaging is vulnerable to deceptive jamming, while conventional whole-aperture subsection shift-frequency modulation sequentially applies multiple frequency shifts in slow time, causing reduced temporal support for each component as the number of designed false targets increases. To overcome this limitation, this work proposes a metasurface-enabled spatial-block subsection shift-frequency modulation method for SAR deceptive jamming. The metasurface aperture is divided into independently controlled spatial blocks, where each block performs an individual subsection shift-frequency sequence within the same synthetic aperture interval. A coherent SAR echo model incorporating spatial-block responses, aperture weighting, complex superposition, and measured static amplitude–phase characteristics is established. Three complete SAR imaging cases are considered, including the unmodulated case and the whole-aperture and spatial-block modulation cases constrained by the measured static response. Component-level control cases are further introduced to separate the effects of participating aperture and temporal support. Although incomplete phase coverage and reflection-magnitude variations introduce additional sidelobes and amplitude imbalance, the dominant false-target positions remain consistent with theoretical predictions. These results verify the effectiveness of spatial–slow-time parallel modulation for enhancing the controllability of metasurface-enabled SAR deceptive jamming.