skrf.calibration.calibration.LMR16

class skrf.calibration.calibration.LMR16(measured, ideals, ideal_is_reflect=True, sign=None, switch_terms=None, *args, **kwargs)[source]

SixteenTerm Load-Match-Reflect self-calibration.

16-Term self calibration for leaky VNA. Implementation is based on [1].

Needs five standards to be measured and given in this order:
  • Through
  • Match-match
  • Reflect-reflect
  • Reflect-match
  • Match-reflect

Reflect standard needs to be very reflective and same in all measurements. Matching of through and match standards is assumed to be perfect. Loss of the through is assumed to be zero, but its length can be non-zero.

Only reflect or through standard needs to be known and the other one will be solved during the calibration. Solved S-parameters of the standards can be accessed with LMR16.solved_through and LMR16.solved_reflect.

Switch termination is already assumed to be done either by the previous calibration or during the measurements. Regular switch correction equations used with EightTerm calibration can’t be used if leakage is significant.

References

[1]
  1. Silvonen, “LMR 16-a self-calibration procedure for a leaky network analyzer,” in IEEE Transactions on Microwave Theory and Techniques, vol. 45, no. 7, pp. 1041-1049, Jul 1997

Attributes

T_matrices Intermediate matrices used for embedding and de-embedding.
biased_error Estimate of biased error for overdetermined calibration with multiple connections of each standard
caled_ntwk_sets Returns a NetworkSet for each caled_ntwk, grouped by their names
caled_ntwks List of the corrected calibration standards
coefs Dictionary or error coefficients in form of numpy arrays
coefs_12term Dictionary of error coefficients for 12-term Model
coefs_12term_ntwks Dictionary or error coefficients in form of Network objects
coefs_3term Dictionary of error coefficients for One-port Error model
coefs_3term_ntwks Dictionary of error coefficients in form of Network objects
coefs_8term Dictionary of error coefficients for 8-term (Error-box) Model
coefs_8term_ntwks Dictionary of error coefficients in form of Network objects
coefs_ntwks Dictionary of error coefficients in form of Network objects
error_ntwk The calculated error Network or Network[s]
family
frequency Frequency object of the calibration.
measured_unterminated
normalized_directivity the directivity normalized to the reflection tracking
nstandards number of ideal/measurement pairs in calibration
output_from_run Returns any output from the run().
residual_ntwk_sets Returns a NetworkSet for each residual_ntwk, grouped by their names
residual_ntwks Dictionary of residual Networks
solved_reflect Return the solved reflect or the ideal reflect if through was solved
solved_through Return the solved through or the ideal through if reflect was solved
total_error Estimate of total error for overdetermined calibration with multiple connections of each standard.
unbiased_error Estimate of unbiased error for overdetermined calibration with multiple connections of each standard
verify_12term
verify_12term_ntwk

Methods

E_matrices Convert solved calibration T matrices to S-parameters.
__init__ LMR16 initializer
apply_cal Apply correction to a Network
apply_cal_to_all_in_dir
apply_cal_to_list Apply correction to list of dict of Networks.
embed
from_coefs Creates a calibration from its error coefficients
from_coefs_ntwks Creates a calibration from its error coefficients
plot_caled_ntwks Plots corrected calibration standards
plot_errors Plots biased, unbiased and total error in dB scaled
plot_residuals Plot residual networks.
pop Remove and return tuple of (ideal, measured) at index.
remove_and_cal Remove a cal standard and correct it, returning correct and ideal
run Runs the calibration algorithm.
terminate Terminate a network with switch terms
unterminate Unterminates switch terms from a raw measurement.
update_coefs update currect dict of error coefficients
write Write the Calibration to disk using write().