HP 8753D - Page 294

S-parameters
are exactly
equivalent to
the more
common
description
terms
below
,
requiring
only
that the
measurements
be
taken
with
all
test
device
ports
properly
terminated.
S-P
arameter
Denition
T
est
Set
Description
Direction
S
11
b
1
a
1
a
2
=
0
Input
reection
coecient
FWD
S
21
b
2
a
1
a
2
=
0
F
orward
gain
FWD
S
12
b
1
a
2
a
1
=
0 Reverse
gain REV
S
22
b
2
a
2
a
1
=
0
Output
reection
coecient
REV
The
S-P
arameter
Menu
The
S-parameter
menu
allows
you
to
dene the
input ports
and test
set direction
for
S-parameter
measurements
.
The
analyzer
automatically
switches the
direction of
the
measurement
according
to
the
selections
you
made in
this menu.
Therefore,
the analyzer
can
measure
all
four
S-parameters
with
a
single connection.
The S-parameter
being measured
is
labeled
at
the
top
left
corner
of the
display.
The
S-parameter
menu
contains
the
following
softkeys:
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
Refl:
FWD
S11
(A/R)
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
NN
NN
NN
NN
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
NN
NN
NN
NN
N
N
N
N
N
N
N
N
N
N
N
Trans:
FWD
S21
(B/R)
N
N
N
N
N
N
N
N
N
N
N
N
NN
NN
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
NN
NN
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
Trans:
REV
S12
(A/R)
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
NN
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
NN
N
N
N
N
N
N
N
N
N
Refl:
REV
S22
(B/R)
N
N
N
N
N
N
N
N
NN
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
NN
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
ANALOG
IN
Aux
Input
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
NN
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
NN
N
N
CONVERSION
[
]
provides
access
to
the
conversion
menu.
N
N
N
N
N
N
N
N
N
N
NN
NN
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
INPUT
PORTS
provides
access
to
the
input ports
menu.
Analog
In
Menu
This
menu
allows
you
to
monitor
voltage
and
frequency
nodes
,
using
the
analog bus
and
internal
counter
.
F
or
more
information,
refer
to
Chapter
10,
\Service
Key
Menus and
Error
Messages"
in
the
HP
8753D
Network
Analyzer
Service
Guide
.
Conversion
Menu
This
menu converts the measured reection or transmission data to the equivalent complex
impedance
(Z) or admittance (Y) values
. This is not the same as a two-port Y or Z parameter
conversion, as
only the measured parameter is used in the equations
. Two simple one-port
conversions are available
, depending on the measurement conguration.
An S
11
or S
22
trace measured as reection can be converted to equivalent parallel impedance or
admittance using the model and equations shown in Figure 6-9.
Application and Operation Concepts 6-27