Analysis of Superstrate-Loaded Cylindrical Microstrip Lines inside a Grounded Conducting Cylinder

The objective of this research is to study the effects of the superstrate on a microstrip line mounted inside a grounded conducting cylinder. A rigorous full wave analysis is applied to formulate an electric field integral equation, which is subsequently solved numerically using the method of moments. A spectral dyadic Green's function that relates the electric fields to the surface currents on the strip and accounts for all the boundary conditions on the interfaces across different dielectric layers is derived. Entire domain basis functions for the surface currents are employed in the numerical computation. Computed results include the effective dielectric constants and the characteristic impedances of the propagation modes. Since results for the present structure have not been reported elsewhere, computed frequency dependent results can only be compared with data available in the literature for some special cases. The computer code developed in this research can be used as a computer aided tool in the pre-fabrication stage in the circuit design process.