Keysight E8663D, Руководство пользователя

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254 Keysight E8357D/67D & E8663D PSG User’s Guide
Multitone Waveform Generator
Creating, Viewing, and Optimizing Multitone Waveforms
The waveform has nine tones spaced 1 MHz apart with random initial phase
values. The center tone is placed at the carrier frequency, while the other eight
tones are spaced in 1 MHz increments from the center tone. If you create an
even number of tones, the carrier frequency will be centered between the two
middle tones.
Figure 9-2
To View a Multitone Waveform
This procedure describes how to configure the spectrum analyzer to view a
multitone waveform and its IMD products. Actual key presses will vary,
depending on the model of spectrum analyzer you are using.
1. Preset the spectrum analyzer.
2. Set the carrier frequency to 20 GHz.
3. Set the frequency span to 20 MHz.
4. Set the amplitude for a 10 dB scale with a 4 dBm reference.
5. Adjust the resolution bandwidth to sufficiently reduce the noise floor to
expose the IMD products. A 9.1 kHz setting was used in our example.
6. Turn on the peak detector.
7. Set the attenuation to 14 dB, so you’re not overdriving the input mixer on
the spectrum analyzer.
You should now see a waveform with nine tones and a 20 GHz center carrier
frequency that is similar to the one shown in Figure 9-3 . You will also see IMD
products at 1 MHz intervals above and below the highest and lowest tones.