Design and modelling of IC-Stripline having improved VSWR performance

This paper presents design and modelling of an open version of the IC-Stripline manufactured on the FR-4 substrate and connected by SMA connectors and MS lines. Three versions of the IC-Stripline are presented and improvement in VSWR performance is gradually obtained. The first version of the IC-Stripline has PCB ground plane on the bottom layer. Although this version has several advantages, it requires multilayer PCB in order to provide shielding for fixture lines used for DUT connection. The second version of the IC-Stripline has the PCB ground plane on the top layer. Although the significant improvement in VSWR performance is obtained, the second version of the IC-Stripline does not have VSWR lower than 1,2 over the frequency range up to 3 GHz. The 3D EM simulations are used to optimize the tapered sections of the IC-Stripline in order to improve VSWR performance. The geometrical parameters of the notch are optimized and the obtained VSWR is less than 1,2 over the frequency range up to 3 GHz. The optimized version of the IC-Stripline is measured and improvement in VSWR performance is confirmed. Also, the circuit models for IC-Stripline and end-launch SMA connector are presented.