Investigation of Ground Coplanar Line on RO4003® Substrate 0.51 mm

50 Ohms Ground Coplanar Waveguide (GCPW) on RO4003® substrate with thickness 0.51 mm is investigated numerically and experimentally. The grounding via-hole distance L = 2 - 6 mm is optimized for operation bandwidth in the frequency range 1 - 18 GHz. The simulated frequency dependence of the effective permittivity is found to be 4.5 percent against 2 percent of measured values. Numerical simulations predict decreasing of the 50 Ohms characteristic impedance value up to 43-44 Ohms around 18 GHz.