Probe Pad Structures for Multi Module Scheme at 76GHz Band

A novel type of probe pad structures for coplanar line probe have been proposed which can be used for multi module scheme applications with each module containing millimeter wave integrated circuits with package having interfaces with microstrip line at 76GHz band. The main emphasis is placed to design such probe pad structures by taking into account the electromagnetic field interactions between the microstrip line and unused grounding probe pads which exist at the interconnecting plane of multi module scheme. The shape of grounding probe pads, the width of center conductor probe pad or the gaps between the grounding probe pads and the center conductor probe pad and the length of the taper to 50¿ microstrip line are optimized by tackling simultaneously the problems of probe impedance mismatch and the propagating microstrip mode interactions with the unused grounding probe pads at the interface of multi module system. Successful applications are practically demonstrated.