Agilent Technologies 4395A, Manual Change

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Calibration for Network Measurement
T able A -2. Standard Denitions
NO .
Standard
Type
C0
210
015
F
C1
210
027
F/Hz
C2
210
036
F/Hz
2
Oset
Delay
ps
Oset
Loss
M/s
Oset
Z
0
Standard
Label
1
2
3
4
5
6
7
8
Each standard must be identied as one of ve \types": OPEN, SHORT , LO AD , DELA Y/THRU ,
or arbitrary impedance .
Standard Types
OPEN
OPENs assigned a terminal impedance of innite ohms , but delay and loss osets may
still be added. F or information of the delay and loss osets , see the \Oset and Delay"
paragraph.
As a reection standard, an OPEN oers the advantage of broadband frequency
coverage . However , an OPEN rarely has perfect reection characteristics because
fringing (capacitance) eects cause phase shift that varies with frequency . This can be
observed in measuring an OPEN termination after calibration, when an arc in the lower
right circumference of the Smith chart indicates capacitive reactance . These eects are
impossible to eliminate , but the calibration kit models include the OPEN termination
capacitance at all frequencies for compatible calibration kits . The capacitance model is a
second order polynomial (squared term), as a function of frequency , where the polynomial
coecients are user-denable . The capacitance model equation is:
C = C
0
+ C
1
2 F + C
2
2 F
2
where F is the measurement frequency .
SHORT
SHORT s are assigned a terminal impedance of 0 , but delay and loss osets may still be
added.
LO AD
LO ADs are assigned a terminal impedance equal to the system characteristic impedance Z
0
,
but delay and loss osets may still be added. If the LO AD impedance is not Z
0
, use the
arbitrary impedance standard denition.
DELA Y/THRU
DELA Y/THRUs are assigned a transmission line of specied length, for calibrating
transmission measurements .
ARBIT ARY IMPED ANCE
A-46 Basic Measurement Theory