skrf.calibration.calibration.EightTerm¶
 class skrf.calibration.calibration.EightTerm(measured, ideals, switch_terms=None, isolation=None, ut_hook=None, *args, **kwargs)[source]¶
General EightTerm (aka Errorbox) Twoport calibration.
This is basically an extension of the oneport algorithm to twoport measurements, A least squares estimator is used to determine the error coefficients. No selfcalibration takes place. The concept is presented in 1 , but implementation follows that of 2 .
See
__init__()
Notes
An important detail of implementing the errorbox model is that the internal switch must be correctly accounted for. This is done through the measurement of switch terms.
References
 1
Speciale, R.A.; , “A Generalization of the TSD NetworkAnalyzer Calibration Procedure, Covering nPort ScatteringParameter Measurements, Affected by Leakage Errors,” Microwave Theory and Techniques, IEEE Transactions on , vol.25, no.12, pp. 1100 1115, Dec 1977. URL: http://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=1129282&isnumber=25047
 2
Rytting, D. (1996) Network Analyzer Error Models and Calibration Methods. RF 8: Microwave Measurements for Wireless Applications (ARFTG/NIST Short Course Notes)
Attributes
Intermediate matrices used for embedding and deembedding. 

Estimate of biased error for overdetermined calibration with multiple connections of each standard. 

Return a NetworkSet for each caled_ntwk, grouped by their names. 

List of the corrected calibration standards. 

Dictionary or error coefficients in form of numpy arrays. 

Dictionary of error coefficients for 12term Model. 

Dictionary or error coefficients in form of Network objects. 

Dictionary of error coefficients for Oneport Error model. 

Dictionary of error coefficients in form of Network objects. 

Dictionary of error coefficients for 8term (Errorbox) Model. 

Dictionary of error coefficients in form of Network objects. 

Dictionary of error coefficients in form of Network objects. 

The calculated error Network or Network[s]. 



Directivity normalized to the reflection tracking. 

Number of ideal/measurement pairs in calibration. 

Return any output from the 

Returns a NetworkSet for each residual_ntwk, grouped by their names. 

Dictionary of residual Networks. 

Estimate of total error for overdetermined calibration with multiple connections of each standard.This is the combined effects of both biased and unbiased errors. 

Estimate of unbiased error for overdetermined calibration with multiple connections of each standard. 

Methods
EightTerm Initializer. 

Apply correction to a Network. 

Apply correction to all touchstone files in a given directory. 

Apply correction to list of dict of Networks. 

Apply correction to a NetworkSet. 

Create a calibration from its error coefficients. 

Create a calibration from its error coefficients. 

Plot corrected calibration standards. 

Plot biased, unbiased and total error in dB scaled. 

Plot residual networks. 

Remove and return tuple of (ideal, measured) at index. 

Remove a cal standard and correct it, returning correct and ideal. 

Renormalizes the calibration error boxes to a new reference impedance. 

Run the calibration algorithm. 

Terminate a network with switch terms. 

Unterminates switch terms from a raw measurement. 

Update current dict of error coefficients. 

Write the Calibration to disk using 