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Importance and estimation of mismatch uncertainty for RF parameters in calibration laboratories

Published online by Cambridge University Press:  26 September 2012

K. Patel  and
P.S. Negi
K. Patel*
Affiliation:
Amorphous and Microcrystalline Silicon Solar Cells, CSIR-National Physical Laboratory, New Delhi, India
P.S. Negi
Affiliation:
Electrical Standards, CSIR-National Physical Laboratory, New Delhi, India
*
⋆ Correspondence: kpatel@nplindia.org
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Abstract

A number of calibration techniques are used in Radio Frequency (RF) calibration for power, attenuation and impedance parameters. Mismatch uncertainty plays a major role in these measurements and in estimation of combined uncertainty according to ISO/IEC 17025:2005 and GUM document. Formulas to evaluate the mismatch uncertainty in terms of reflection coefficient, voltage standing wave ratio and scattering parameters have been evaluated earlier and are being used in RF calibration. The present paper summarizes the mismatch formulas previously studied and the modified ones suitable to the measurement system and techniques available today. For power and attenuation calibration in the particular frequency range, an establishment of traceability for one-port measurement in the same frequency range is required. The methods to reduce and control this uncertainty component and their limitations are also discussed forbest measurements practices in the calibration laboratories.

Keywords

Mismatch uncertaintyRF attenuationRF powerimpedance traceabilityvector network analyzer
Type
Research Article
Information
International Journal of Metrology and Quality Engineering , Volume 3 , Issue 1 , 2012 , pp. 29 - 37
Copyright
© EDP Sciences 2012

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References

E. Hund, Microwave Communication – Components and Circuits (McGraw-Hill Book Company, 1987)
G. Kennedy, Electronic Communication Systems (McGraw-Hill Education, Ltd., India, 1994)
Beatty, R.W., Mismatch errors in the measurement of ultrahigh frequency and microwave variable attenuators, Journal of Research National Bureau of Standards 52, 7–9 (1954) CrossRefGoogle Scholar
Schafer, G.E., Rumfelt, A.Y., Mismatch errors in the cascade-connected variable attenuators, IRE Transactions of Microwave Theory and Techniques 7, 447–453 (1959) CrossRefGoogle Scholar
Microwave mismatch error analysis, Hewlett-Packard Application note 56, 1967
R.W. Beatty, Microwave Attenuation measurements and standards, NBS Monograph 97 (1967)
Microwave measurements, edited by R. Collier, D. Skinner (IET Publication, 2009)
Hollway, D.L., Kelly, F.P., A standard attenuator and the Precise measurement of Attenuation, IEEE Trans. Instrum. Meas. 13, 33–44 (1964) CrossRefGoogle Scholar
S. Whitacre, Dee Humpherys, Low level power measurement techniques and accuracy, HP RF & Microwave measurement symposium and exhibition (USA, 1968)
Engen, G.F., Recent development in the field of microwave power measurements at the National Bureau of Standards, IRE Trans. Instrum. 3, 304–306 (1958) CrossRefGoogle Scholar
R.W. Beatty, Coaxial Power, impedance and attenuation calibration methods at NBS, Microwave J., 65–75 (1968)
ISO, ISO/IEC 17025, General requirements for the competence of testing and calibration laboratories (2005)
Guidelines on the evaluation and expression of the measurement uncertainty, Singapore Institute of Standards and Industrial Research (1995)
Guide to the expression of uncertainty in measurement, Geneva, International Organization for Standardization (1993)
EA Guidelines on the Evaluation of Vector Network Analyzers (VNA), Publication reference EUROMET/cg-12/v0.1 (2007)
G.H. Bryant, Principles of microwave measurements (Peter Peregrinus Ltd., 1988)
F.L. Warner,Microwave Attenuation measurement (Peter Peregrinus Ltd., 1977)
A.E. Bailey, Microwave measurements (IEE Publication, 1989)
Bayer, Horst, Warner, F.L., Yell, R.W., Attenuation and Ratio – National Standards, Proc. IEEE 74, 46–59 (1986) CrossRefGoogle Scholar
Bayer, H., An error analysis for the RF attenuation measuring equipment of the PTB applying the power method, Metrologia 11, 43–51 (1975) CrossRefGoogle Scholar
Warner, F.L., New expression for mismatch uncertainty when measuring microwave attenuation, IEE Proc. 127, 66–69 (1980) Google Scholar
R.S. Yadava, R. Swarup, K. Chandra, Technical report on Audio frequency substitution technique for measurement of Microwave attenuation, Report No. MWA-1, 1983
R. Swarup, R.S. Yadava, K. Chandra, Technical report on Microwave attenuation measurement by IF substitution technique, Report No. MWA-2, 1983
Harris, I.A., Warner, F.L., Re-examination of mismatch uncertainty when measuring microwave power and attenuation, IEEProc. 128, 35–41 (1981) Google Scholar
Weinschel, B.O., Standardization of precision coaxial connectors, Proc. IEEE 55, 923–931 (1967) CrossRefGoogle Scholar
Coaxial connectors in Radio frequency and microwave measurements, NAMAS, NIS 4303 (1991), Vol. 1
D. Skinner, ANAMET Connector guide-Guidance on using Coaxial connectors in measurement, ANAMET Report 032, 2001
IEEE Std. 287-2007, IEEE Standard for Precision coaxial connectors (DC to 110 GHz) (IEEE Instrumentation and Measurement Society, USA, 2007)