Millimeter-wave System-in-Package (SiP) for Non-Destructive Testing of Metallic Structures under Multilayered Composites using Backward-to-Forward Beamscanning Leaky Wave Antenna

In this work the design, analysis and characterisation of a novel backward to forward scanning substrate integrated waveguide (SIW) leaky wave antenna with consistently high gain over the entire field of view is proposed. The leaky wave antenna (LWA) achieves beamforming from the backward to forward direction with change in frequency. The antenna measures 5.64λ0 × 1.5λ0 × 0.0294λ0 at the centre frequency of 60 GHz and has an operating frequency range from 56 to 70 GHz with a gain > 9.5 dBi throughout the operating frequency range. The main beam direction changes from -53° to 50° as the frequency varies from 56 to 70 GHz. The designed leaky wave antenna is integrated with a mm-wave transceiver that is designed as a System-In-Package (SiP) and the complete system is used to carry out measurements to validate non-destructive testing (NDT) for metallic structures with defects under insulating materials such as foam, laminated plastic, composites and ceramics. The designed SiP measures 100 mm × 60 mm. The measured results demonstrate that the developed system is capable NDT and scanning of metallic structures under multilayered composites.