To Minimize Carrier Feedthrough - Keysight E8267D User Manual

Two–Tone Waveform Generator
Creating, Viewing, and Modifying Two–Tone Waveforms
Figure 10-3

To Minimize Carrier Feedthrough

This procedure describes how to minimize carrier feedthrough and measure
the difference in power between the tones and their intermodulation distortion
products. Carrier feedthrough only occurs with center–aligned two–tone
waveforms.
This procedure builds upon the previous procedure.
1. On the spectrum analyzer, set the resolution bandwidth for a sweep rate
2. On the signal generator, press I/Q > I/Q Ad justments > I/Q Ad justments
3. Press I Offset and turn the rotary knob while observing the carrier
4. Press Q Offset and turn the rotary knob to further reduce the carrier
5. Repeat steps 3 and 4 until you have reached the lowest possible carrier
6. On the spectrum analyzer, return the resolution bandwidth to its previous
Keysight E8357D/67D & E8663D PSG User's Guide
Two–Tone
Channels
Intermodulation
Distortion
of about
100 to 200 ms. This will allow you to dynamically view the carrier
feed through spike as you make adjustments.
Off On to On.
feed through with the spectrum analyzer. Changing the I offset in the
proper direction will reduce the feed through level. Adjust the level as low
as possible.
feed through level.
feed through level.
setting.
Carrier
Feedthrough
Carrier Feedthrough
Distortion
265