Anritsu VectorStar ME7838 Series, Maintenance Manual, Page: 71 / 178

Theory Of Operation 4-6 ME7838A System Operation—Waveguide Band Configuration
VectorStar ME7838 Series MM PN: 10410-00306 Rev. F 4-11
4-6 ME7838A System Operation—Waveguide Band Configuration
This section describes the system operation of the Waveguide Band ME7838A VNA System.
Stimulus Signal Generation
The MS464xA or MS464xB VNA outputs an RF signal to the 3739A, 3739B or 3739C Test Set.
In the test set, the RF signal is then routed to the Port 1 RF Output or Port 2 RF Output via a transfer switch
after amplified and fed to the 3744A Millimeter-Wave Modules.
In the 3744A Millimeter-Wave Module, the frequency of the RF signal is either doubled or tripled and then
output to the DUT.
For operation between 56 GHz and 80 GHz, the frequency of the RF signal is doubled in the module. For
operation between 80 and 110 GHz, the frequency of the RF signal is tripled.
Test Signal Processing
The MS464xA or MS464xB VNA outputs two LO signals to the 3739A, 3739B or 3739C Test Set. The LO
signals are amplified (and attenuated, if required). It is then routed to Port 1 LO Output or Port 2 LO Output
and fed to the 3744A Millimeter-Wave Modules.
In the 3744A Millimeter-Wave Module, a sample of the stimulus signal is down-converted to intermediate
frequency (IF) using the LO signal from the 3739A, 3739B or 3739C Test Set. The output is the Reference IF
signal.
The reflected/transmitted test signal received at the Waveguide test port of the 3744A module is coupled to the
test channel down-converter which converts the test signal to IF signal using the LO signal from the 3739A,
3739B or 3739C Test Set. The output is the Test IF signal.
Both the Reference and Test IF signals are then fed to the 3739A, 3739B or 3739C Test Set. The IF signals
pass through the 3739A, 3739B or 3739C Test Set and are fed to the IF Inputs of the MS464xA or MS464xB
VNA for further signal processing.