Modeling Signals using Interface Blocks in SysML

Question

I'm trying to model a port that consists of several signals. Each signal can be one two signal types. Each signal type has a signal level and impedance. Some signals have a pulse duration. What is the best way to model this? I have made an interface port with each signal represented as a flow property. Then I made two value types each with its own constraints on impedance and voltage level. Each signal in the interface block's flow property list is then marked with the value type. Is this the best way to do this?

Thanks

Answer 1

Since each "signal" has several properties a way to bind the set of properties together is needed. I would therefore use an Interface-Block for each "signal".

Please note, that SysML uses the word "signal" with a different meaning.

While it is possible to use flow properties, I don't think they are the best fit here. Usually they are used to show that something is flowing. The thing flowing here would be electrical charge - and this is probably not the level of detail appropriate here. We could say, that the information about the voltage is flowing, but what about the impedance?

So, my suggestion is to use required value properties:

These can then be used individually, or as nested ports, when a grouping is required: