We describe a coherent imaging technique that utilizes a diffraction grating placed near the object to alias high spatial frequency information through the imaging system pupil. The resulting optical field in the image plane is detected by means of digital holography. Multiple measurements are taken with the grating shifted by a fraction of its period between exposures. Linear signal processing is then used to separate the aliased spectral components, and Fourier techniques are applied to

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... truct high-resolution images. Experimental results validate the approach, yielding an enhancement in resolution by a factor of 2.6 when using five diffracted beams (orders up to ±2).