A Demonstration of the Near-Field Imaging Modes Using UHF Imaging Probe

A super-resolution near-field ultrahigh frequency (UHF) imaging probe has been recently introduced. This electrically small UHF probe is consist of a square loop loaded with a spiral resonator (SR), resonating at 426 MHz (free space wavelength lambda approximate to 740 mm) with overall footprint 7.2 mm x 7.2 mm. In this paper, three distinct imaging modes using this probe are demonstrated. These imaging modes utilize single or swept frequency RF source in order to image the sample under test (SUT). A comparative investigation of the obtained microwave images through these imaging modes is carried out. It is found here that the cost-effective near-field imaging system can be realized with the UHF probe by utilizing its single frequency measurement mode.