1、Designation:D7449/D7449M22aStandard Test Method forMeasuring Relative Complex Permittivity and RelativeMagnetic Permeability of Solid Materials at MicrowaveFrequencies Using Coaxial Air Line1This standard is issued under the fixed designation D7449/D7449M;the number immediately following the designa
2、tion indicates theyear of original adoption or,in the case of revision,the year of last revision.A number in parentheses indicates the year of lastreapproval.A superscript epsilon()indicates an editorial change since the last revision or reapproval.1.Scope*1.1 This test method covers a procedure for
3、 determiningrelative complex permittivity(relative dielectric constant andloss)and relative magnetic permeability of isotropic,reciprocal(non-gyromagnetic)solid materials.If the material isnonmagnetic,it is acceptable to use this procedure to measurepermittivity only.1.2 This measurement method is v
4、alid over a frequencyrange of approximately 1 GHz to over 20 GHz.These limitsare not exact and depend on the size of the specimen,the sizeof coaxial air line used as a specimen holder,and on theapplicable frequency range of the network analyzer used tomake measurements.The size of specimen dimension
5、 islimited by test frequency,intrinsic specimen electromagnetismproperties,and the request of algorithm.For a given air linesize,the upper frequency is also limited by the onset of higherorder modes that invalidate the dominant-mode transmissionline model and the lower frequency is limited by the sm
6、allestmeasurable phase shift through a specimen.Being a non-resonant method,the selection of any number of discretemeasurement frequencies in a measurement band would besuitable.The coaxial fixture is preferred over rectangularwaveguide fixtures when broadband data are desired with asingle sample or
7、 when only small sample volumes areavailable,particularly for lower frequency measurements.1.3 The values stated in either SI units of in inch-poundunits are to be regarded separately as standard.The valuesstated in each system are not necessarily exact equivalents;therefore each system shall be use
8、d independently of the other.Combining values from the two systems is likely to result innon conformance with the standard.The equations shown hereassume an e+jtharmonic time convention.1.4 This standard does not purport to address all of thesafety concerns,if any,associated with its use.It is there
9、sponsibility of the user of this standard to establish appro-priate safety,health,and environmental practices and deter-mine the applicability of regulatory limitations prior to use.1.5 This international standard was developed in accor-dance with internationally recognized principles on standard-iz
10、ation established in the Decision on Principles for theDevelopment of International Standards,Guides and Recom-mendations issued by the World Trade Organization TechnicalBarriers to Trade(TBT)Committee.2.Referenced Documents2.1 ASTM Standards:2D150 Test Methods for AC Loss Characteristics and Permit
11、-tivity(Dielectric Constant)of Solid Electrical InsulationD1711 Terminology Relating to Electrical Insulation3.Terminology3.1 For definitions of terms used in this test method,refer toTerminology D1711.3.2 Definitions of Terms Specific to This Standard:3.2.1 A list of symbols specific to this test m
12、ethod is givenin Annex A1.3.2.2 calibration,na procedure for connecting character-ized standard devices to the test ports of a network analyzer tocharacterize the measurement systems systematic errors.Theeffects of the systematic errors are then mathematically re-moved from the indicated measurement
13、s.The calibration alsoestablishes the mathematical reference plane for the measure-ment test ports.3.2.2.1 DiscussionModern network analyzers have thiscapability built in.There are a variety of calibration kits thatcan be used depending on the type of test port.The modelsused to predict the measurem
14、ent response of the calibrationdevices depends on the type of calibration kit.Most calibrationkits come with media that can be used to load the definitions ofthe calibration devices into the network analyzer.Calibration1This test method is under the jurisdiction of ASTM Committee D09 onElectrical an
15、d Electronic Insulating Materials and is the direct responsibility ofSubcommittee D09.12 on Electrical Tests.Current edition approved Sept.1,2022.Published October 2022.Originallyapproved in 2008.Last previous edition approved in 2022 as D7449/D7449M 22.DOI:10.1520/D7449_D7449M-22A.2For referenced A
16、STM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.org.For Annual Book of ASTMStandards volume information,refer to the standards Document Summary page onthe ASTM website.*A Summary of Changes section appears at the end of this standardCopyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United StatesThis international standard was developed in accordance with internationally recognized principles on standard
