Your remark about prepending array size put me right on track
![ThumbsUp :-+](https://www.eevblog.com/forum/Smileys/default/icon_smile_thumbsup.gif)
I guess it goes like: Uint size, frequencies, Uint size, Ch1 complex, etc.
I started with VSWR too, was fun to try-and-error a Vivaldi out of copper tape. When the Smith chart shows a bit too much inductance, cut some tape and make the coupling capa larger... Works like a charm, got the SWR below 1.2 in the entire 2.4 G ISM band (need directional antennas for the radar). Now I have the rough shape, will cut it out of copper sheet and put it in a can (side lope suppression) to reduce direct path reception.
Its amazing what this little thing can do, but your software is definitively the icing on the cake. Reference subtraction, all the options for stimulus, automatic marker placement, ... incredible.
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