Web-Based Linear, Frequency Domain Simulator - Page 1
Forum section: electronics / rf-microwave

author: guywithanidea
author_rank: Newbie
timestamp: March 26, 2022, 09:09:58 pm
content: All,Longtime lurker but first time poster, but I am in the final steps of building up a web-based design tool for S-Parameter measurements. One thing that I have been working on is that some COTS parts will be preloaded in the simulator to save people the work of picking things (you can still use your own data). I am trying to get a sense of if it would be useful and who would use it. So far its just connectorized parts but I hope to move into PCB parts and board level design as well. I know you haven't seen it BUT if there was a tool to connect up a bunch of parts and see the typical performance (including adding your own), would you use it? When I have something deployed I'll post it.Edit: as was appropriately called out - it is a linear, frequency domain simulator and I have modified the subject to properly reflect it. thanks for the correction!

author: mc172
author_rank: Frequent Contributor
timestamp: March 26, 2022, 10:46:04 pm
content: I don't see how this is useful - where is the reference plane, how have you connected the device, how have you calibrated your analyser, where did you calibrate relative to the reference plane, what adaptors have you had to use, etc? Having the answers doesn't even help me in the real world, I need to test this stuff for myself. OK, for stuff with connectors on a lot of the questions go away but you mention wanting to go "deeper". This is a bit like relying on ECAD symbols and footprints from Mouser/Farnell/Arrow/RS etc. but 100x worse.

author: guywithanidea
author_rank: Newbie
timestamp: March 27, 2022, 12:25:06 am
content: Thanks for the feedback! So the reference planes are defined in concrete points in the simulator and bulkheads, cables and adapters can either be selected from a preselected library (these are real part numbers you can buy from real manufacturers), or if you have your own that you like and have characterized, you can use those. Calibration is not considered but de-embedding could be implemented from the reference planes I discussed above. As for the realm of PCB level analysis, you are right - these things do matter. I do not have full answers for you yet as I haven't built that portion out but the intent would be to provide a qucs level simulation ability for different types of transmission lines, stubs, potentially filters, and combine it with a library of parts (or your own) to give a first order sense of what something may look like. It is not an EM tool.

author: mc172
author_rank: Frequent Contributor
timestamp: March 27, 2022, 01:08:00 am
content: I still don't see how this helps me in the real world. Suppose I'm interested in a particular device which happens to be in your library - you've measured it using a particular set of test leads and a particular set of adaptors and I want to use this device in my product. Now I've got to buy the same adaptors that you used (which you've kindly provided the part numbers for) in order to verify your test results - why would I do this? In reality I'd just buy the device that I want and test it myself to verify that it matches the manufacturers' datasheet and get on with the job.

author: guywithanidea
author_rank: Newbie
timestamp: March 27, 2022, 01:57:03 am
content: Makes sense to me, but what if you want to look at a combo of 5 parts? 15 parts? That can get costly depending on the parts. Maybe its a build with tight deadlines and do not have the luxuries of time. It seems to be of value to know how it will all play together roughly prior to some kind of monetary commitment on parts you might never need or not want.If your just building 1 or two things at a time as the needs and itch arise then I see your point.

author: Marsupilami
author_rank: Frequent Contributor
timestamp: March 28, 2022, 04:38:14 am
content: So is it a linear, frequency domain simulator? I don't get the "measurement" part. How is this different then let's say QUCS other than being web based? (not to mention the big ones)I can give audacious feature requests.

author: guywithanidea
author_rank: Newbie
timestamp: March 29, 2022, 01:04:27 pm
content: Yea I probably didn't describe it in the best way... it is a linear, frequency domain simulator yes.With all of these simulators, they never share any part information when they sell you their tool and that always ticked me off. Just generic transistors and Opamps. so I want to provide data (data from manufacturers with real buyable part numbers) out of the box. From there I think it would be easier to go from an initial concept to a initial design. I run into this constantly in my work and just came to the conclusion that its probably something other people deal with too.