I
-
Making Basic Measurements Using Spectrum Analyzer Mode
Identifying Distortion Products Using the RF Attenuator and Traces
Third-Order
Intermodulation
Distortion
Two-tone, third-order inter-modulation distortion is a common problem
in communication systems. When two signals are present in a system,
they can mix with the second harmonics generated and create third-order
inter-modulation distortion products, which are located close to the original
signals. These distortion products are generated by system components such
as amplifiers and mixers.
Example: Test a device for third-order inter-modulation. This example uses
two sources, one set to 300 MHz and the other to approximately 301 MHz.
(Other source frequencies may be substituted, but try to maintain a frequency
separation of approximately 1 MHz.)
1. Connect the equipment as shown in Figure 4-23.
Figure 4-23. Third-Order Intermodulation Equipment Setup
4-34
