How do you create cal kit data for a custom VNA SOLT cal kit?

I have a custom built calibration kit for a 2-port VNA calibration. I have not been able to find a method of getting the calibration kits standards. Has anyone done this before?

I have measured each standard after calibrating the VNA with the HP85033D 3.5mm cal kit. The operation manual for an HP8573D indicates how to modify a custom user kit, but not how to come up with the values. I will try to extract the definitions from the s-parameters of the custom standards. But, any help would be appreciated. Thank you in advance. Bob

I forgot to mention that the structure is non-typical. For port 1, there is approximately 3/4" trace to a large pad. Port 2 is a direct connect to the same large pad.

I do not have any experience in creating a cal kit, but I have read a bit on it since reading your post. This paper seems enlightening:

http://cp.literature.agilent.com/litweb/pdf/5989-4840EN.pdf

I would like to know how this goes, you will have to keep us posted.

Hi Bob:

basically you will be fitting a specific model to your cal standards. Generally, the models are:

load:
a transmission line of specifiec characteristic impedance with specified electrical length to a resistor.

Open:
a transmission of specified characteristic impedance and specified electrical length to a capacitor, usually specified as a polynomial function of frequency.

Short:
same as open, except the end is an inductor usually specified as a polynomial function of frequency.

Thru:
transmission line of specified characteristic impedance and specified electrical length.

often there is a loss term, assumed to be skin-effect loss (goes as square-root of frequency) which is specified at one frequency point.

Some instruments (like the one I make) allows the s-parameters of the standard to be entered directly, so whatever model you use, you would just enter the model in the simulator and export the s-parameters. You could also measure your standard on a calibrated VNA and directly use these measured s-parameters as your standards.

After rereading your question, you will need to determine the values of your model through simulation, although you will need to match this simulation to an actual measurement if you want to be successful.

Hello Peter,

Thank you for your input. What I am not sure of is whether the VNA will accept two different cal standards. I did find an Agilent data sheet on creating custom cal kits, so I'll have to make some time for that. Reference link: http://edocs.soco.agilent.com/display/iccapmhb/Defining+Custom+Calkits

Warm Regards,
Bob