
110 Chapter 3
Basic Digital Operation
Understanding Waveform Clipping
How Clipping Differs from Symbol Offset in W-CDMA
Another method used to control the power peak problem in a W-CDMA waveform is to modify
the symbol-offset values of the channels that comprise either the I or Q waveform. This is
accomplished by using the signal generator’s W-CDMA channel table editor. Unlike clipping,
which reduces existing peaks, this method attempts to prevent peaks.
When multiple channels use a framing structure in which certain bits are designed to have
the same state, these bits align and are summed to create power peaks. Offsetting the
symbols in the channels prevents these bits from aligning, creating a cancelling effect. You
can experiment with using the symbol-offset method in combination with clipping.
Comentarios a estos manuales