Far-field time reversal super-resolution imaging of sources at microwave wavelengths aided by a grating-like slow-wave plate

For realizing super-resolution imaging in far-field region, a finite-sized grating-like slow-wave plate is designed to collect near-field evanescent waves which encode sub-diffraction-limit details of targets. Numerical results show that, with the help of wavenumber modulation, sub-diffraction-limit informations can be carried to far-field region and recorded. At last, time reversal imaging processes are applied to reconstruct the image of two small dipole sources with a resolution smaller than 0.5λ. This kind of grating-like slow-wave plate is easy to fabricate and provides a promising alternative for far-field super-resolution imaging in microwave region.