Effective utilization of coaxial connector for millimeter wave multilayer device testing

The paper presents an effective technique for utilization of a coaxial connector for millimeter wave measurements of multilayer planar microstrip devices, such as antennas, any passive circuits, or RF chip components integrated on a board. The technique is based on partial end face metallization of a board, which provides effective electrical connection of the microstrip ground plane located on an internal metal layer and an outer conductor of the coaxial connector. It is experimentally demonstrated that utilization of the proposed technique provides a significant improvement of millimeter wave measurements accuracy by lowering the insertion loss. Additionally the technique has no band limitations and can be used from low frequencies up to 100 GHz and above. The proposed technique can be considered as an alternative to waveguide-to-microstrip transitions commonly used for millimeter wave testing or down conversion of the signal frequency before the measurements.