What is actually "F" variable in "TLinP" component of ADS

Hi all,

I am studying about using the "TLinP" component of ADS:

http://edocs.soco.agilent.com/displa...l+Physical+Tra...

For most variables, I understand what they are. However, what is the meaning of the "F" variable ? I guess that it is not just a frequency of interest. From the document, it specifies that "F" is "Frequency for scaling attenuation". What does this mean actually ? :o

Thanks a lot and merry Christmas,

DYL

Surely see Notes/Equations 1 in the above.