Synthetic-aperture direct-detection coherent imaging
نویسنده
چکیده
This paper describes an approach to coherent aperture synthesis and fine-resolution image reconstruction employing phase retrieval from intensity measurements. A Gerchberg-Saxton algorithm is used on a pair of intensity measurements to obtain the fields for each telescope at each position of the telescopes without a reference beam. These are combined into a larger synthetic aperture, and a cross-correlation is used to sense and correct for piston, tip and tilt phases of each of the sub-apertures with respect one another, giving a much higher resolution than from a single aperture. Results of simulations, including the effects of speckle, are shown, and practical considerations are evaluated.
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