HP 8753D - Page 427

In
standard vector
error-correction, a
thru (delay=0)
is
used
as
a
calibration
standard.
The
solution
to this
problem
is
to
use
a
calibration
mixer
with
very
small
group
delay as
the
calibration
standard.
An
important characteristic
to
remember
when
selecting
a
calibration
mixer
is
that
the
delay
of
the device
should
be
kept
as
low
as
possible
.
T
o
do
this
,
select a
mixer with
very wide
bandwidth
(wider bandwidth
results in
smaller
delay).
6-160 Application and Operation Concepts