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Microwave synthesis that tells you whether it can be etched.
Enter a specification, get real dimensions, a layout drawing, the predicted response and a KiCad footprint — plus the one thing no free calculator will tell you: whether a fabricator can actually hold the features your design needs.
Edge-coupled bandpass filter
Parallel-coupled half-wave resonators — the classic microstrip bandpass. Widest bandwidth of the three, and the easiest to etch.
Synthesize → unconfirmedHairpin bandpass filter
Edge-coupled resonators folded into hairpins. Roughly half the board length of a straight coupled-line filter at the same order.
Synthesize → indicativeInterdigital bandpass filter
Quarter-wave bars grounded at alternating ends. Compact and steep, with a wide spurious-free window above the passband.
Synthesize → validatedWilkinson power divider
Two-way split with matched ports and isolation between the outputs, set by a single bridging resistor.
Synthesize → validatedBranch-line coupler
Quadrature hybrid: an equal split with 90° between the outputs. Four quarter-wave arms in a ring.
Synthesize →What makes this different
The manufacturability check. Every result is measured against a real shop's published process envelope — Lintek's, transcribed from their capabilities document. A 0.10 mm coupled-line gap is not "tight", it is a specific answer: too fine for the standard process, within reach of the special one. That is a question you want answered before you spend a cent, and it is the question most calculators leave you to discover at quote time.
Cited models, with their validity ranges. Microstrip closed forms are fits, valid over a stated range, and outside it they return numbers that look fine and are not. Every result names the model it used and the range it is good for, and the engine warns rather than extrapolating quietly.
Substrates with design permittivity. RO4350B at 3.66, RO4003C at 3.55 — the datasheet design values that reproduce measured circuit performance, not the IPC process values and certainly not εr = 4.4 for everything. On a 4.75 GHz hairpin that distinction is about 95 MHz of centre frequency, which is a fifth of the passband.
It says when it is unsure. Each topology carries a label saying how far its predicted response has actually been verified — validated against published data, not yet confirmed against full-wave EM, or indicative only. They are not all the same, and presenting them as though they were would be the one genuinely dishonest thing a tool like this could do.
Not here, and why
Coupled-line directional coupler. Built, but its directivity is an unverified prediction — and directivity is the only number that decides whether the part is usable.
Radial / butterfly stub. Not built. The curved-geometry primitive is done; the synthesis is not.
2P's own rule for the engine is that if a capability is not built and functional, it is not claimed. The website inherits that rule.
Want a design verified full-wave?
Closed-form synthesis is a starting point, not a guarantee. Send us a design and we will run it through a full-wave EM solve and come back with the S-parameters and an engineer's read on what they mean.
Ask for an EM verification →These get built in Australia.
2P Innovation designs, fabricates and assembles RF hardware locally, to Class 3, fully documented.
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