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

Return 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

Directivity normalized to the reflection tracking.

nstandards

Number of ideal/measurement pairs in calibration.

output_from_run

Return 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.This is the combined effects of both biased and un-biased errors.

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 correction to all touchstone files in a given directory.

apply_cal_to_list

Apply correction to list of dict of Networks.

apply_cal_to_network_set

Apply correction to a NetworkSet.

embed

from_coefs

Create a calibration from its error coefficients.

from_coefs_ntwks

Create a calibration from its error coefficients.

plot_caled_ntwks

Plot corrected calibration standards.

plot_errors

Plot 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

Run the calibration algorithm.

terminate

Terminate a network with switch terms.

unterminate

Unterminate switch terms from a raw measurement.

update_coefs

Update current dict of error coefficients.

write

Write the Calibration to disk using write().