Back-To-Back Tapered Balun
I am using HFSS to simulate two back to back tapered baluns. HFSS gives me plots of the S-Parameters for a range of frequencies.
My question is, how can I know what are the S-Parameters of only one balun?
I think that I simply need to add 3dB to all the results. But I am not sure.
You are measuring or simulating the entire set of hardware including the interactions between the halves.
actually the design does not consist of two objects... the two baluns were 'united' into one object (ie. no discontinuity between the two)... I just want to know how to manipulate the S-Paramater data of the two back to back baluns so that I can get the S-Paramater data for one balun...
Hi,
this is not the trivail task at all. Having the results of a single back-to-back case is not conclusive enough - you can't get ANY info on S parameters of single balun, as Fatulent already wrote.
I can't remember exactly where, but I came accross a method comprising of having diffrent line length between the two baluns in back-to-back arangement. Then it was possible to use something like de-embedding to get some info (if not all) about S parameters of a single balun. I might have time to search further of this topic, but can't promise you anything.
flyhigh
Presumably you have a back to back balun because this is what you can measure. This is of course the joy of HFSS and the like, why not just simulate a single balun?
Hey Matt,
The reason I don't simulate one balun is because I would have to place some kind of absorbing material at the end of it to prevent any reflections. I've seen many papers do the back - to - back design for this very reason. Unfortunately they don't specify how to extract the data for only one balun... which is what they care about.
Hi,
the reason back-to-back arangement is always seen in the papers is becouse it is the only way to measure it (you can't connect any connectors on unbalanced port)
You can simulate single balun in HFSS, no need to put any absorber to avoid reflections, if you have reflections in the simulations than your balun is not well matched.
flyhigh
hey mesalem
please upload your hfsss files
Hey flyhigh,
Why cant we connect connectors to unbalanced end? I have simulated many structures by connecting an SMA connector which is an unbalanced connector. So i still dont get the reason of simulating back to back baluns.
Thanks