Agilent Technologies 8510-58 ∆∅radians = 2πf ∆length, Short circuit inductance L0 , L1, L2 and L3

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Figure 3. Time domain response of open at the end of an airline

Note

In some cases (when the phase response is linear with respect to frequency) the response of an open can be modeled as an equivalent “incremental” length.

∆∅(radians) = 2πf (∆length)

c

This method will serve as a first order approxima- tion only, but can be useful when data or stan- dards for the above modeling techniques are not available.

For the waveguide example, this parameter is not addressed since opens cannot be made valid stan- dards in waveguide, due to the excessive radiation loss and indeterminant phase.

Short circuit inductance L0 , L1, L2 and L3

If the standard type selected is a ‘short,’ the L0 through L3 coefficients are specified to model the phase shift caused by the standard’s residual inductance as a function of frequency. The reflec- tion coefficient of an ideal zero-length short is 1 at 180° at all frequencies. At microwave frequencies, however, the residual inductance can produce additional phase shift. When the inductance is known and repeatable, this phase shift can be accounted for during the calibration.

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Contents Product Note 8510-5B Table of contents Measurement calibration Measurement errorsIntroduction Calibration kit Class assignment Standard definitionStandard definitions table Standard class assignments Select standards Modification procedureStandard definition models Define standardsOpen circuit capacitance C0 , C1 , C2 and C3 Standard numberStandard type ΠfZ ΠfXShort circuit inductance L0 , L1, L2 and L3 ∆∅radians = 2πf ∆lengthTerminal impedance Offset delayDelay seconds = Fixed or slidingOffset Z0 Linear delay Actual delay = Fco/f210 log10e εr Offset loss1GHz = 1GHz c Z0Lower/minimum frequency ∅radians = Upper/maximum frequencyFupper = 2 x Flower Coax or waveguideStandard Classes Assign classesStandard labels Isolation S11 A,B,C and S22 A,B,CForward transmission match and thru Reverse transmission match and thruTRM Thru TRL ThruTRL Reflect TRL LineCalibration kit label Standard Class labelsTRL options Verify performance Enter standards/classesModeling an arbitrary impedance standard User modified cal kits and Agilent 8510 specificationsModification examples Modeling a thru adapterTo store calibration kits from the Agilent 8510 onto a disk Appendix a Calibration kit entry procedureDisk procedure To load calibration kits from disk into AgilentFront panel procedure P-band waveguide example Pshort Type-N coaxial connector interface Appendix B Dimensional considerations in coaxial connectorsMm coaxial connector interface Female type-N Mm Coaxial connector Type-N coaxial connector interfacePage Equation Appendix C Cal coefficients modelTheir first order approximations, R is small and G=0, are Then Online assistance Phone or Fax United States