SmithDroid - RF Calculator

SmithDroid is a portable RF and microwave engineering workbench built around an interactive Smith chart. Design matching networks, analyze two-port data, size planar circuits and inspect exported simulation models on Android. Interactive Smith Chart & Matching • Explore impedance and admittance grids with an editable load point and matching paths. • Calculate reflection coefficient, VSWR and return loss as your network changes. • Synthesize two- and three-element L, Pi and T matching networks, or build cascaded ladders manually. • Transfer matching elements into transmission-line and stub realizations. Touchstone & Transistor Stability • Import two-port .s2p files and explore their frequency samples. • Calculate Rollett k, determinant Δ, μ and μ′, with stability-circle overlays. • Explore series-resistance and shunt-conductance stabilization candidates. • Synthesize bilateral source and load matches and evaluate gain. Transmission Lines & Packaging • Analyze microstrip width and length, or synthesize geometry from impedance and electrical length. • Define substrate permittivity, loss tangent, height and copper thickness. Estimate conductor loss, dielectric attenuation and skin depth. • Calculate coplanar waveguide impedance, effective permittivity, wavelength and electrical length, with an optional backside ground plane. • Estimate through-silicon via DC and AC resistance, skin depth, oxide capacitance and partial inductance. • Use illustrated CPW and TSV cross-sections to understand geometry and input parameters. Passive Circuits & Verification • Synthesize equal, unequal and N-way Wilkinson dividers, branch-line hybrids and rat-race couplers. • Explore radial and curved stubs, bends, impedance steps, gaps, crosses and grounding vias. • Sweep network response for return loss, insertion loss and isolation. • Assess tolerances, parasitics and fabrication limits before moving to layout. Portable HFSS Model Viewer • Preview supported geometry from Ansys HFSS .aedt projects or open exported OBJ meshes. • Preserve assigned project colors and distinguish objects with outlines. • Tap or search for objects to highlight, isolate and inspect them. • Rotate, pan and zoom in 3D, use preset camera views or open fullscreen. • Control visibility, transparency, shading, mesh edges and Z clipping. Reset View restores the default scene. • Inspect available materials, dimensions, variables, boundaries and solution settings. Unsupported geometry is reported explicitly. Simulation Reports • Import CSV or TAB reports, select traces and variations, and inspect individual samples. • Combine separate magnitude and phase exports when their sweep grids match. • View rectangular, Smith, polar, radiation-pattern and stacked plots, or inspect a data table. • Explore complete two-axis grids as filled contours, rotatable 3D surfaces or 3D bar plots. • Interpret real/imaginary, magnitude/phase and dB/phase data. Convert resistance/reactance to Smith-chart coordinates using a reference impedance. • Use expandable instructions to prepare HFSS report exports. Clear Navigation & Equation Guides Dedicated Match, Lines, Circuits, S-Params, HFSS and Guides tabs keep related tools together. Calculator introductions, diagrams and expandable settings provide context, while equation guides explain units, conventions and model assumptions. SmithDroid uses closed-form equations and compact models for rapid prototyping, learning and early design checks. It complements full-wave EM simulation and VNA measurements. Imported files are processed on the device. The viewer supports a subset of AEDT geometry and does not run HFSS or read raw .aedtresults databases. Export numerical results as CSV, TAB or two-port Touchstone files. Grid and radiation views display exported numeric data, not reconstructed field solutions. SmithDroid is an independent application, not affiliated with or endorsed by Ansys. Ansys and HFSS are trademarks of their respective owner.