Calculation of Mutual Admittance Between CPW-Fed Slots on Two-Layer Conductor-Backed Substrates Using Reciprocity-Based Expression

A computational strategy, based on a well-known reciprocity-based formulation, for finding the mutual admittance Y₁₂ between CPW-fed slots on conductor-backed two-layer substrates is presented. Simplifying assumptions make it possible to determine Y₁₂ against inter-slot spacing d by performing a once-only moment-method analysis of each slot in isolation, and then calculating external and internal reaction integrals at each value of d. It is shown that Y₁₂ against d calculated for CPW-fed twin slots on conductor-backed two-layer substrates agrees well with simulations of the full twin-slot structure using the moment-method-based simulator IE3D.