15
Section 9
Tracking Generator: Transmission and Reflection Measurements
A spectrum analyzer with tracking generator can be used to perform compo-
nent tests such as frequency response and gain and loss on components and
subsystems. The tracking generator is a signal source whose RF output follows
(tracks) the tuning of the spectrum analyzer. The N9340B spectrum analyzer
has an optional high-performance, built-in tracking generator (Option TG3),
operating from 5 MHz to 3 GHz. A tuned receiver architecture and narrow IF
bandwidths provide high dynamic range for scalar component test.
The N9340B spectrum analyzer can be used to characterize measure transmis-
sion parameters, such as fl atness and rejection, or refl ection parameters,
such as return loss on devices under test (DUTs). Return loss is an a reflection
measurement requiring a directional coupler or bridge.
Transmission measurements
In the following demo, the rejection of a bandpass fi lter is measured.
In the following demo, a 300 MHz bandpass fi lter is used as a DUT.
The marker readout displays the rejection of the fi lter at 90 MHz above the
center frequency of the band pass.
Figure 7. Transmission measurement setup
DUT
N9340B
HANDHELD SPECTRUM ANALYZER
100
kHz - 3.0
GHz
SYS
MODE
MEAS
TRACE
BW/
SWP
AMPTD
SPAN
FREQ
ENTER
MARKER
ESC/ CLR
1
ABC
2
DEF
3
GHI
4
JKL
5
MNO
6
PQR
7
STU
8
VWX
9
YZ_
0
SAVE
LIMIT
PRESET
