Table of Contents
Advertisement
Operation
Using the 11970A, Q, U, V, and W Mixers with the X- Series Signal Analyzers (Option EXM)
Signal ID
Image Suppress
The Image Suppress mode of Signal ID mathematically removes all image and multiple responses of
signals present at the mixer input. Two hidden sweeps are taken in succession. The second sweep is
offset in LO frequency by 2*IF/N. For each point in each trace, the smaller amplitude from the two
traces is taken and placed in that point in Trace 1. Responses of each trace that lie on top of one another
will remain and are valid signals, others are images and are suppressed.
This function takes control of and uses Trace 1. Any data in this trace prior to
NOTE
activating Image Suppress will be lost.
In Image Suppress Mode, synchronization is ensured by first turning off Signal ID, initiating a single
sweep, then turning on Signal ID followed by two single sweeps.
Image Shift
Like the Image Suppress mode, Image Shift is a two sweep sequence. The data from the first sweep is
placed in Trace 1 and the data from the second (LO frequency shifted by 2*IF/N) sweep is placed in
Trace 2. Signal responses of Trace 1 and Trace 2 that have the same horizontal position are considered to
be in the current band and therefore can be analyzed with the amplitude and frequency measurement
systems of the SA. All other responses are invalid and should be ignored.
This function takes control of and uses Trace 1 and Trace 2. Any data in these
NOTE
traces prior to activating Image Shift will be lost.
To synchronize in Image Shift Mode, turn off Signal ID and then initiate a single sweep. Then turn on
Signal ID and initiate two single sweeps. The results of the first sweep after Signal ID is turned on are
available in Trace 1. The next sweep is shifted and the data from that sweep is available in Trace 2. The
unshifted and shifted data can then be compared.
38
Advertisement
Table of Contents
