Microwave split-ring resonator array for imaging of near-surface material defects

This novel study shows that, compared to a single microwave split-ring resonator (SRR), the image quality and detection accuracy of near-surface material defects can be significantly improved with the use of an N × M - channel SSR array. An example 3 × 3 array of independently driven SRRs was modelled to image 2 mm wide near-surface cracks in concrete and aluminium with S-parameters recorded over a frequency span of 3.5-6.5 GHz. Images with improved quality were obtained with the new multi-channel SRR array. It is hoped that this is an initial step in the direction of implementing a near-surface microwave camera system prototype.