Agilent Technologies E8257D, User Manual

Page: 135 / 318

Chapter 3 121
Basic Digital Operation
Using Waveform Clipping
appears as a rectangle in the vector representation. With either method, the objective is to clip the
waveform to a level that effectively reduces spectral regrowth, but does
not compromise the integrity
of the signal. Figure 3- 16 on page 123 uses two complementary cumulative distribution plots to show
the reduction in peak–to–average power that occurs after applying circular clipping to a waveform.
The lower you set the clipping value, the lower the peak power that is passed (or the more the signal
is clipped). Often, the peaks can be clipped successfully without substantially interfering with the rest
of the waveform. Data that might be lost in the clipping process is salvaged because of the error
correction inherent in the coded systems. If you clip too much of the waveform, however, lost data is
irrecoverable. You may have to try several clipping settings to find a percentage that works well.
Figure 3-14 Circular Clipping