Actually knowing the type of the reflect standard corrects the S22 phase.

Igor

--- In mtt-11@yahoogroups.com, "igorlinetsky" <igor_linetsky@...> wrote:
>
> Thank you Dylan
>
> When S21=S12 there is a 180deg ambiguity in the answer because of the
> square root function. Similarly, there is a square root to solve for
> S22 of the input adapter that gives another 180deg ambiguity.
>
> The first 180deg ambiguity is ok because usually we need S12*S21
> products and as long as the same 180deg error is made in calculating
> both S-parameters of the input and the output adapters, the DUT
> deembedding will be correct. However I'm not sure the 180deg ambiguity
> in S22 of the input adapter is as easy to deal with.
>
> BTW, I'd like to write a matlab routine to determine the full
> S-parameters of the input and the output adapters.
>
> Regards
> Igor
>
> >
> > Sorry Igor,
> >
> > When de-embedding adapters you can use reciprocity
> (S21=S12) to
> > solve this problem. Both MultiCal and StatistiCAL allow you to solve
> for
> > adapter scattering parameters with multiline TRL, and that would be
> a good
> > place to start.
> >
> > Next time I will have to be more careful about getting the
> reply
> > to you!
> >
> > Best,
> >
> > Dylan
> >
> >
> > At 03:54 PM 7/22/2008, you wrote:
> >
> > >Hello Dylan
> > >
> > >Looks like you replied to my message but the text did not show?
> > >
> > >Regards
> > >Igor
> > >
> > >--- In <mailto:mtt-11%40yahoogroups.com>mtt-11@yahoogroups.com,
Dylan
> > >Williams <dylan@> wrote:
> > > >
> > > > At 07:46 AM 7/22/2008, you wrote:
> > > >
> > > > >Hello
> > > > >
> > > > >I've been following Doug Rytting presentation called "TRL
> > > > >Calibration". The equations all make sense and give good results
> > > > >however the presentation does not seem complete as it does not
> discuss
> > > > >how to do the final step of separating e10e32 and e23e01 terms
> (these
> > > > >terms are the S12's and S21's of the two error adapters).
> > > > >
> > > > >Can anybody help me with this? I'd like to determine the
> S-parameters
> > > > >of the two error adapters.
> > > > >
> > > > >Thank you
> > > > >Igor
> > > > >
> > > > >
> > > >
> > > >
> > > >
> > > > -----------------------------------------------------
> > > > Dylan Williams <dylan@>
> > > > NIST 818.01 <dylan@>
> > > > 325 Broadway [+1] (303)497-3138 (TEL)
> > > > Boulder CO 80305 USA [+1] (303)497-3970 (FAX)
> > > >
> <http://www.boulder.nist.gov/dylan/>http://www.boulder.nist.gov/dylan/
> > > > -----------------------------------------------------
> > > >
> > >
> > >
> >
> >
> >
> > -----------------------------------------------------
> > Dylan Williams <dylan@>
> > NIST 818.01 <dylan@>
> > 325 Broadway [+1] (303)497-3138 (TEL)
> > Boulder CO 80305 USA [+1] (303)497-3970 (FAX)
> > http://www.boulder.nist.gov/dylan/
> > -----------------------------------------------------
> >
>