HP 85106D, Manual

Page: 84 / 244

HP 85106D mm-Wave System 2-39
Operation
Multiple Source
Multiple Source
ON for HP 85105 mm-Wave Controller
OFF for Coaxial Test Set
Multiple Source Definitions are required for each mm-wave band. Multiple
source settings are shown in Figure 2-12 on page 2-40 for all the mm-wave
bands. These definitions load automatically when the hardware state is
loaded. Examine these by pressing:
[
SYSTEM
] {
MORE
} {
EDIT MULT.SRC
.}
QuickSTEP does not work in multiple source mode.
As an example of how multiple source control works, consider a Q band
system (33 GHz to 50 GHz) set to measure from 42 GHz to 48 GHz at 201
points. For the 101st measurement point along the sweep the test signal
frequency at the DUT is 45 GHz. To generate this 45 GHz signal, the test
signal source is set to 15 GHz, amplified, and its frequency is tripled in the
test set module (3 X 15=45). The incident, reflected, and transmitted
portions of the 45 GHz signal are separated in the test set module and
applied to the first frequency conversion stage. Inside each harmonic mixer
the 45 GHz signal is mixed with the tenth harmonic of the LO source to
produce an IF signal of 20 MHz. This means the tenth harmonic of the LO
source is at 45.020 GHz. The LO source fundamental frequency is at
4.502 GHz (10 X 4.502=45.020). The same approach may be used to show
that for the entire 201 point sweep, the test signal source sweeps from 14 to
16 GHz while the LO source sweeps from 4.202 to 4.802 GHz.