Near-Field Microwave Imaging Antenna Array for Inline Intrusion Detection of Processed Products

The presence of foreign bodies in packaged products can be assessed exploiting inline microwave imaging (MWI) inspection systems. The purpose is to illustrate an insight of the product's composition according to the dielectric properties of its constituents, by processing the scattering parameters of an array of antennas. This allows to unveil the position and shape of any potential extraneous material, with the advantage of a non-invasive, non-destructive and real-time testing. While the resulting dielectric contrast reconstructions depict a visual and qualitative overview of the analyzed item, quantitative metrics are essential to objectively evaluate their outcome. In this paper, we exploit size, overlap and boundary metrics to investigate the performances of a MWI system, made of an array of extended gap ridged slotted horn antennas, in locating a glass sphere, placed inside a commercial cocoa-spread jar, all numerically modeled.