Agilent Technologies 8510-58 Upper/maximum frequency, Fupper = 2 x Flower, Coax or waveguide

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Upper/maximum frequency

This specifies the maximum frequency at which the standard is valid. In broadband applications, a set of banded standards may be necessary to pro- vide constant response. For example, coaxial offset standards (i.e., 1/4 λ offset short) are generally spec- ified over bandwidths of an octave or less. Bandwidth specification of standards, using mini- mum frequency and maximum frequency, enables the 8510 to characterize only the specified band during calibration. Further, a submenu for banded standards is enabled which requires the user to completely characterize the current measurement frequency range. In waveguide, this is the upper cutoff frequency for the waveguide class and mode of propagation. For the fundamental mode of prop- agation in rectangular waveguide the maximum upper cutoff frequency is twice the lower cutoff frequency and can be calculated as follows.

F(upper) = 2 x F(lower)

The upper frequency of a waveguide standard may also be specified as the maximum operating fre- quency as listed in a textbook.

The MAXIMUM FREQUENCY of the WR-62 wave- guide cal kit is 18.974 GHz and is entered into the standard definition table for all four standards.

Coax or waveguide

It is necessary to specify whether the standard selected is coaxial or waveguide. Coaxial transmis- sion line has a linear phase response as

(radians) =

2π

= 2πf(delay)

λ

 

 

Waveguide transmission line exhibits dispersive phase response as follows:

(radians) = 2π λg

where

λg = λ

1-( / co)2

Selection of WAVEGUIDE computes offset delay using the dispersive response, of rectangular wave- guide only, as a function of frequency as

Delay (seconds) = Linear delay 1-(fco/f)2

This emphasizes the importance of entering “fco” as the LOWER FREQUENCY.

Selection of COAXIAL assumes linear response of offset delay.

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Contents Product Note 8510-5B Table of contents Introduction Measurement errorsMeasurement calibration Calibration kit Standard definition Class assignmentStandard definitions table Standard class assignments Modification procedure Select standardsDefine standards Standard definition modelsStandard type Standard numberOpen circuit capacitance C0 , C1 , C2 and C3 ΠfX ΠfZ∆∅radians = 2πf ∆length Short circuit inductance L0 , L1, L2 and L3Offset delay Delay seconds =Fixed or sliding Terminal impedanceLinear delay Actual delay = Fco/f2 Offset Z0Offset loss 1GHz =1GHz c Z0 10 log10e εrLower/minimum frequency Upper/maximum frequency Fupper = 2 x FlowerCoax or waveguide ∅radians =Standard labels Assign classesStandard Classes S11 A,B,C and S22 A,B,C Forward transmission match and thruReverse transmission match and thru IsolationTRL Thru TRL ReflectTRL Line TRM ThruTRL options Standard Class labelsCalibration kit label Enter standards/classes Verify performanceUser modified cal kits and Agilent 8510 specifications Modification examplesModeling a thru adapter Modeling an arbitrary impedance standardAppendix a Calibration kit entry procedure Disk procedureTo load calibration kits from disk into Agilent To store calibration kits from the Agilent 8510 onto a diskFront panel procedure P-band waveguide example Pshort Mm coaxial connector interface Appendix B Dimensional considerations in coaxial connectorsType-N coaxial connector interface Mm Coaxial connector Type-N coaxial connector interface Female type-NPage Appendix C Cal coefficients model EquationTheir first order approximations, R is small and G=0, are Then Online assistance Phone or Fax United States