DIRECT ANALYTICAL SOLUTION FOR THE ELECTRIC-FIELD DISTRIBUTION AT THECONDUCTOR SURFACES OF COPLANAR WAVE-GUIDES

A new analytical method of evaluating the electric field distribution across the conductor surfaces of coplanar waveguides (CPW's) is presen ted. Here, a series of conformal mappings are employed to transform th e CPW's geometry and field distribution into a uniform image domain, t o facilitate a direct field solution. The cumulative electric flux dis tribution across each conductor surface within the dielectric substrat e is studied, and its effects on coupling and propagation modes are de scribed. Direct solutions for the quasistatic normal electric field co mponents are presented together with their graphical representations. Numerical computations show how the total electric flux terminating on the CPW's conductor surfaces varies in terms of the CPW's geometry an d substrate parameters.