Tutorial: Microstrip Filter Design

This page is the filter-side counterpart to the patch workflow:

use the guide pages for API and solver concepts
prefer the latest committed crossval when a public runnable reference exists
treat older convenience examples as legacy unless they are explicitly re-qualified

Recommended workflow

Stage	Goal	Primary page / script
1. Geometry + ports	Build the coupled lines, substrate, and two-port setup correctly	Sources & Ports, Probes & S-Parameters
2. Practical public reference	Wait for a currently promoted crossval-backed filter reference	current page intentionally stays guide-only for now
3. Evidence framing	Position the result relative to the broader validation story	Cross-Validation & Accuracy

Current public posture

This workflow is still documented as a guide path rather than as a crossval-first public reference. That means:

Parameter	Value
Status	guide workflow only
Public example priority	lower than the current promoted patch crossval
What is still needed	a clearly promoted, currently trusted crossval-backed filter reference

What this public path proves

The current guide path is intended to answer a practical question:

Can the present rfx two-port microstrip workflow produce a sensible coupled-line bandpass response at the intended design frequency?

Before this becomes a promoted public example path again, it should be tied to a freshly selected crossval/benchmark reference and phrased through the current validation contract.

Interpretation rules

Do not treat older convenience examples as the primary public microstrip filter reference automatically.
Keep the broader support/claim framing anchored to Cross-Validation & Accuracy.
Only promote a runnable filter script once it is explicitly selected as the current trusted crossval-backed reference.

Where to go next

Sources & Ports for two-port setup details
Probes & S-Parameters for frequency-domain extraction
Cross-Validation & Accuracy for how to phrase public evidence claims