The Type B extraction is a simplification of Type A in that it only requires a pair of one port cals. This can be useful if a thru connect is difficult because of adapter/fixture configuration issues. This particular algorithm has a long history and is covered in the literature extensively (for example, R. Bauer and P. Penfield, “De-embedding and unterminating,” IEEE Trans. Micr. Theory Tech., vol. 22, pp.282-288, Mar. 1974.). As suggested by the figure below, a cal is performed at Plane 1 (often a coaxial or waveguide cal) and a second cal is performed at Plane 2 (could also be coaxial or waveguide in the case of an adapter or could be more complicated in the case of a fixture).

As before, the cals are performed and the setups saved, typically as an active channel CHX file type. The cal files are retrieved using the dialog below.

 

After Perform Network Extraction is selected, another dialog appears asking for the file name where the resulting S2P data should be saved. Different cal algorithms and media types may be selected but at least Cal B must be 1-Port only. Cal A can be a full two port cal or a double 1-Port cal (this way it is known how to compute the extraction). As with Type A, the adapter/fixture is assumed to be reciprocal and the frequency lists must be the same.

The results obtained with Type B may be somewhat different from those obtained with Type A since the algorithms are not the same. The main differences will be with respect to outboard match (at Plane 2 in Figure: Network Extraction Type B Reference Planes above). In Type A, this match is determined with a full reflectometer solve while in Type B, it is determined with a source-match like extraction on the error X of the second cal. As a result, the Type B extraction of this match will be somewhat more sensitive to cal quality than will Type A (particularly with regard to the source match-determining cal components: O and S in OSL or the two shorts in SSL). The trade-off is simplicity and, in some cases, practicality.