Study of subwavelength imaging from a single broadband antenna

Subwavelength imaging is a long sought-after goal in various imaging applications, which usually require an array of antennas or mechanical scanning. Here, we present the concept of single antenna for imaging with the aids of metamaterial lens and compressive sensing processing. We propose, design, and realize a spatial-temporal resonant metamaterial lens based on a planar array of closely spaced resonators, which provides the unique ability to produce real-time data when illuminated by broadband electromagnetic waves. A sparsity-promoted reconstruction algorithm is specially developed to process the data acquired by the single-antenna imaging system. We demonstrate experimentally that this novel imaging system, in combination with the advanced reconstruction algorithm, is capable of producing high-resolution images without using mechanical scanning or antenna arrays. We expect that the imaging methodology will make breakthroughs in high-resolution imaging in microwave, terahertz, optical, and ultrasound regimes.