Coplanar Waveguide (CPW/GCPW) Impedance Calculator
This calculator estimates the characteristic impedance (Z₀) and effective dielectric constant (ε_eff) of Coplanar Waveguide (CPW) and Grounded Coplanar Waveguide (GCPW) structures using Conformal Mapping.
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CPW & GCPW Fundamentals
Coplanar Waveguide (CPW):
A transmission line structure featuring a single center conductor routed alongside two flanking ground planes on the same layer. The separation gaps (slot width \(S\)) and line width (\(W\)) determine the impedance. Since it avoids vias to ground, it is ideal for connecting shunt elements in high-speed RF modules.
Grounded Coplanar Waveguide (GCPW):
Also known as Coplanar Waveguide with Backing Plane (CBCPW). This structure appends a solid ground plane to the back of the dielectric substrate, enhancing field confinement, optimizing isolation, and minimizing radiation leakage at high microwave frequencies.