UNI-T UTG2122B, Руководство пользователя

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UTG2000B Series 81
4) Use channel output
5) Press CH1 button start channel 1 output quickly. Or enable output by pressing Utility and
then CH1 Setting . After channel output is opened, backlight of CH1 button is on, and on the
right side of channel information label, the font “OFF” changes to
“
DSBAM”, meaning open
channel output.
Figure 3 - 11 Use channel output
Waveform displayed on the oscilloscope
3.1.12 Quadrature Amplitude Modulation(QAM)
In QAM, two signals of the same frequency but with phase difference of 90° (normally indicated by
Sin or Cos) are used as carrier wave, which is subject to amplitude modulation with baseband signal.
UTG2000B function/arbitrary waveform generator can output seven modulation modes: 4QAM,
8QAM, 16QAM, 32QAM, 64QAM, 128QAM and 256QAM. The modulation mode of the two
channels is mutually independent. You can configure same or different modulation mode for
channel 1 and 2.
Note: to prevent phase deviation, it is suggested to use 10MHz as reference output signal and