HP 8753D - Page 358

F
abricating and
dening calibration
standards for
TRL/LRM
When
calibrating a
network
analyzer
,
the
actual
calibration
standards
must
have
known
physical
characteristics.
F
or
the
reect
standard,
these
characteristics
include
the
oset
in
electrical
delay (seconds)
and
the
loss
(ohms/second
of
delay).
The
characteristic
impedance
,
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N
NN
NN
OFFSET Z0
,is
not used
in the
calculations in
that
it
is
determined
by
the
line
standard.
The
reection
coecient
magnitude
should
optimally
be
1.0,
but
need not
be known
since the
same
reection
coecient
magnitude
must
be
applied
to
both
ports.
The
thru
standard
may
be
a
zero-length
or
known
length
of transmission
line.
The value
of
length
must
be
converted
to
electrical
delay,
just like
that done
for
the
reect
standard.
The
loss
term
must
also
be
specied.
Application and Operation Concepts 6-91