Effects of backside grooving on leakage loss of conductor-backed coplanar waveguide

Leakage loss of grooving conductor backed coplanar waveguide (CBCPW) has been analysed by using the hybrid 2D-FDTD Method and the curve-fitting procedure. From numerical results, it has been confirmed that the leakage-loss of the CBCPW can be reduced over the wide range of operating frequency by constructing the groove on the backside of CBCPW substrate and also predicted the existence of the optimum grooving width. Furthermore, by investigating the relation between the leakage-loss of CBCPW and the position or the size of the backside groove in detail, we discussed what is dominantly affected on the leakage-loss reduction of grooving CBCPW.