Resistance per unit length value is less than what commercial tools give

[ahmedmibrahim]

I was building a similar quasi static solver and got stuck at why the calculated R per unit length value is less than what Polar Si9000e, Hyperlynx, ADS, or even Protoexpress (free online tool) gives. I get similar values like yours, and btw, if you solved the textbook structures (coaxial or twin pair), you will find your R value matching the equations. It seems commercial tools report a higher value for some reason, a value that's very similar to Rdc + Rac /// but no physical sense

[Ttl]

I haven't tried the tools you mentioned, but the solved R matches reasonably well with Ansys 2D extractor.