Ceyear 4041 Series, User Manual

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Chapter XI Performance Characteristics Test
152
analyzer is -30 dBm

0.1 dB.
11) Press
【
Marker
】
[" Differential Mode] to set the center frequency to 12 GHz.
12) Wait for completion of new sweep, and then press
【
Peak
】
. Record the differential marker reading in the
corresponding test item of the "4041 Series Spectrum Analyzer Record Sheet" as the second harmonic
distortion value from 4 GHz to 10 GHz.
Second harmonic distortion (10 GHz~22 GHz)
13) Connect the test instrument as shown in Fig 11-9 and use a 18 GHz low pass filter.
14) Set the frequency of 1464C to 18 GHz and its amplitude to -30 dBm.
15) Set up the spectrum analyzer as follows:
Center frequency 18 GHz
Span ............................................................................................................................................................ 200 Hz
Amplitude ................................................................................................................................................. -30 dBm
Marker ................................................................................................................................................. Markers off
16) Press
【
Peak
】
on the spectrum analyzer. Adjust the power level of 1464C so that the reading of spectrum
analyzer is -30 dBm

0.1 dB.
17) Press
【
Marker
】
[" Differential Mode] to set the center frequency to 36 GHz.
18) Wait for completion of new sweep, and then press
【
Peak
】
. Record the differential marker reading in the
corresponding test item of the "4041 Series Spectrum Analyzer Record Sheet" as the second harmonic
distortion value from 10 GHz to 22 GHz.
11.10 Third-order intermodulation distortion
Description: Third-order intermodulation distortion refers to the unwanted frequency components generated by
the interaction of the spectral components of two or more input signals under the effect of non-linearity of
instruments.
Two synthesized signal generators generate two sine wave signals with frequency space of 100 kHz and with the
same power, and input them into the spectrum analyzer at the same time. The third-order intermodulation
distortion products is then measured indirectly through the marker function of the spectrum analyzer. The filter is
used to filter out the signal distortion product that is closest to the one being measured. The spectrum analyzer
provides a 10 MHz reference frequency for the synthesized signal generator.
Note: If the output of signal generator #1 and signal generator #2 is subject to the load-pull effect and thus the test
result is to be effected, a pair of isolators corresponding to the measurement frequency band can be added to the
output ends of signal generators #1 and #2 respectively to reduce the impact on the test results of third-order
intermodulation distortion.
A) Testing equipment