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How to set boundary condition in RF (emw)?

Posted Jul 17, 2024, 4:10 a.m. EDT Electromagnetics, RF & Microwave Engineering, Physics Interfaces Version 6.2 1 Reply

Yi Xiong
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Hi there. I am confused about setting the boundary conditions in Electromagnetic waves,Frequency domain (emw) module. I am designing an adapter to transmit signal, which is with a main body, 3 rear legs and 3 front legs. The rear/front middle leg is connect to signal while others are connect to ground. 1. Should I set a shell to surround this device, and set it in the specific status (such as scattering Boundary Codition)? 2. When I set the 2 ports in Numeric, the Intergration Line for Voltage seems like a must. How to choose this line and what is it used for? 3. When I try to solve the model, it reports that

"Undefined value found. - Detail: Undefined value found in the equation residual vector. There are 32 degrees of freedom giving NaN/Inf in the vector for the variable comp1.E10..."

Many thanks!

1 Reply Last Post Jul 19, 2024, 12:12 p.m. EDT
Robert Koslover Certified Consultant
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Posted: 2 years ago Jul 19, 2024, 12:12 p.m. EDT
Updated: 2 years ago Jul 19, 2024, 12:16 p.m. EDT

Q1:"Should I set a shell to surround this device, and set it in the specific status (such as scattering Boundary Codition)?" A1: Yes, probably, but I may be misunderstanding what you are talking about. By your phrase "an adapter to transmit signal," do you mean... an antenna? Q2: "When I set the 2 ports in Numeric, the Intergration Line for Voltage seems like a must. How to choose this line and what is it used for?" A2: Not sure what you mean by "the 2 ports." Do you have two ports? Many antennas only need one port. Do you, perhaps, possbly have two wires driving your device, which would technically be only one port? But ok, let's assume you have two ports -- are they both (or just one, or neither) transmitting and/or receiving? Do you need to use numeric ports? Many times simpler RF or lumped ports will work well enough. I'd have to see more about what you are actually trying to do, to answer this question. Q3: "...Undefined value found..." A3: I don't know. I suggest you post your .mph file to the forum.

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Q1:"Should I set a shell to surround this device, and set it in the specific status (such as scattering Boundary Codition)?" A1: Yes, *probably*, but I may be misunderstanding what you are talking about. By your phrase "an adapter to transmit signal," do you mean... an *antenna*? Q2: "When I set the 2 ports in Numeric, the Intergration Line for Voltage seems like a must. How to choose this line and what is it used for?" A2: Not sure what you mean by "the 2 ports." Do you have two ports? Many antennas only need one port. Do you, perhaps, possbly have two *wires* driving your device, which would technically be only *one* port? But ok, let's assume you have two ports -- are they both (or just one, or neither) transmitting and/or receiving? Do you *need* to use numeric ports? Many times simpler RF or lumped ports will work well enough. I'd have to see more about what you are actually trying to do, to answer this question. Q3: "...Undefined value found..." A3: I don't know. I suggest you post your .mph file to the forum.

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