Agilent Technologies 85091C Reference Manual page 11

twelve 1-port standards and three 2-port (thru) standards are measured, requiring a total
of eighteen connections. The same calibration using a 4-port ECal module (N4431B,
N4432A and N4433A) requires only four connections.
Ignoring connection related errors, the following table compares the accuracy of ECal
versus mechanical calibration in various calibration options.
Table 1-1
Mechanical Calibration Type
1-Port, calibration constant (not
data-based) SOL
1-Port, short, open, sliding load
1-Port, data-based, expanded
2-Port TRL
≥2-Port, calibration constant
a
SOL, flush thru
≥2-Port, calibration constant
SOL, unknown thru
≥2-Port, data-based, expanded,
a
flush thru
≥2-Port, data-based, expanded,
unknown thru
++ better; + slightly better; = same
a. Flush thru should NOT be used when the test port connectors are not the same type as the
calibration standards. SMA and 3.5 mm connectors are mateable but are NOT the same
type.
Chapter 1
ECal Thru Measurement
Type
NA Reflection
NA Reflection
NA Reflection
All types Reflection
Transmission
characterized Reflection
Transmission
internal Reflection
unknown Transmission
external Reflection
a Transmission
flush
characterized Reflection
Transmission
internal Reflection
unknown Transmission
characterized Reflection
Transmission
internal Reflection
unknown Transmission
external Reflection
Transmission
a
flush
characterized Reflection
Transmission
internal Reflection
unknown Transmission
General Information
Manual Overview
ECal Mechanical
Calibration
++
+
+
++
++
++ ++
++
++
++ ++
++ =
=
+
++
+
+
+
+
+
++
+
+
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