S parameter extraction from 3D model + external circuits

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Hi everyone,

I’m modeling a two-port piezoelectric resonator that functions as a transformer (per the mBVD representation). I’ve connected the device to an external matching network with a series inductor at the output to cancel Cout, and I’d like to extract the S-parameters of the combined device.

So far: Using Terminal (power) with Terminated boundaries on the 3D structure gives me S-parameters for the bare 3D model only, not the coupled device-and-circuit.

I also tried an Electromagnetic Waves, Frequency Domain (EMW) study, but I’m not confident this is appropriate for a primarily lumped, electromechanical two-port with an external circuit.

Question: What is the recommended workflow to obtain S-parameters when a 3D piezoelectric resonator is connected to external circuitry?

Thank you for any guidance.


1 Reply Last Post 20 ott 2025, 16:31 GMT-4

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Posted: 11 hours ago 20 ott 2025, 16:31 GMT-4
Updated: 11 hours ago 20 ott 2025, 16:32 GMT-4

Without knowing more about the device it's not possible to say whether using emw is necessary or desirable.

I am assuming that you two ports with terminal pairs at input and output. To find a composite set of S parameters, you would build the device + matching components and then apply the S parameter definitions with appropriate sources and terminations. For example, S11 is determined from the input impedance V1/I1 with a matched output. This will require, I think, two separate calculations to get all S parameters.

I don't believe there is any simpler way to do it.

Without knowing more about the device it's not possible to say whether using emw is necessary or desirable. I am assuming that you two ports with terminal pairs at input and output. To find a composite set of S parameters, you would build the device + matching components and then apply the S parameter definitions with appropriate sources and terminations. For example, S11 is determined from the input impedance V1/I1 with a matched output. This will require, I think, two separate calculations to get all S parameters. I don't believe there is any simpler way to do it.

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