In this paper, an analytical method of capacitance and characteristic impedance is proposed, which is for asymmetrical coplanar waveguide with defected ground structure (ACPW-DGS). The capacitance equivalent model of ACPW-DGS is established. Using conformal mapping method and first category of incomplete elliptic integrals F(φ, k), the closed-form expressions of capacitance and characteristic impedance are obtained for the first time. Computed results match the simulated ones well.
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