Cal standard for RF probe
I often make my own standards. If I make a patch antenna with a SMA socket on the back, for example, i have SMA as it is - open, SMA shorted and SMA with two 100ohm chips soldered. Doing the cal with the intended cable using these de-embeds the cable and the S-parameters are true at the antenna port. You can do a similar trick to measure the S-parameters of an i.c. right at the input pins using boards such as it will be put on.