Experimental Investigation on Subwavelength Imaging With Temporal–Spatial Random Illuminations

Although significant progress has been achieved in microwave imaging, high/super-resolution imaging remains a long-sought-after goal. A subwavelength imaging based on temporal–spatial random illuminations is experimentally investigated. Experiments are conducted using a single-frequency array aperture with random phase modulation. The inversion is performed by two different algorithms based on the linear imaging model, and the results show that the location and profile of the object can be successfully reconstructed in a subwavelength scale. In contrast to the broadband meta-assisted imager, an imaging resolution of $0.6\lambda $ is achieved while the spectrum/energy efficiency are both guaranteed in the proposed imaging system. These imply the potential of the presented subwavelength imaging method for practical applications.

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