CAD equivalent-circuit modeling of attenuation and cross-coupling for edge-suspended coplanar waveguides on lossy silicon substrate

In this paper, a compact computer-aided design (CAD)-oriented frequency-independent equivalent-circuit model, taking the skin effect, proximity effect, and substrate effect into consideration, is presented for the edge-suspended coplanar waveguide (ESCPW) on lossy silicon substrate. The ESCPWs exhibit the benefit of reduced loss, while avoid the reliability issues that are associated with the suspended coplanar waveguides. The model shows good agreement with the measured insertion loss and the extracted RLGC line parameters up to 25 GHz. With the model, the relationship between physical perimeters of the ESCPWs and the electrical characteristics is also investigated. Moreover, cross-coupling between adjacent ESCPWs with common ground is characterized and modeled.