Modulation Analysis
R&S
®
Cable Rider ZPH
289
User Manual 1321.0950.02 ─ 07
For Raised Cosine or Root Raised Cosine filter, the filter bandwidth is defined in
term of the alpha value.
For Gaussian filter, the filter bandwidth is defined in terms of the BT value.
Defining the symbol rate and number of signal symbols
The symbol rate defines the number of symbols that are transmitted per time unit (Hz)
from the transmitter. See
Figure 12-4
.
1. Select the "Demod Parameters " softkey.
The R&S Cable Rider ZPH opens a submenu that contains the demodulation
parameters.
2. Select the "Symbol Rate" to define the symbol rate of the measuring signal.
Alternatively, select the "SymR" on the
Parameter View
to define the symbol rate.
The R&S Cable Rider ZPH opens an entry box to enter the symbol rate.
3. Select the "Demod Parameters " >"Number of symbols" to view the number of
modulated symbols.
Alternatively, select "#Sym "on the
Parameter View
to view the number of modula-
ted symbols.
The R&S Cable Rider ZPH displays the number of modulated symbols in the "Sym-
bols" display mode. See
Table 12-5
.
Turning burst processing on and off
Burst processing is a tool similar to a trigger that automatically detects the beginning
and end of a burst in the capture buffer.
A burst is not detected in the following conditions:
●
If the burst power is below a certain threshold
●
If the burst is too short
●
If the time between bursts is too short
Figure 12-5: Burst signal conditions
a = Minimum required signal level
b = Time between bursts
1 = No burst detected as the signal level is below threshold point
Digital Demodulation
