Working With Symbol Rates; To Set A Symbol Rate; To Restore The Default Symbol Rate (Custom Real Time I/Q Only) - Agilent Technologies E8247C PSG CW User Manual

Working with Symbol Rates

The Symbol Rate menu enables you to set the rate at which I/Q symbols are fed to the I/Q modulator. The
default transmission symbol rate can also be restored in this menu.
• Symbol Rate (displayed as Sym Rate) is the number of symbols per second that are transmitted using
the modulation (displayed as Mod Type) along with the filter and filter alpha (displayed as Filter).
Symbol rate directly influences the occupied signal bandwidth.
Symbol Rate is the Bit Rate divided by the number of bits that can be transmitted with each symbol; this
is also known as the Baud Rate.
• Bit Rate is the frequency of the system bit stream. The internal baseband generator (Option 002/602)
automatically streams the selected Data Pattern at the appropriate rate to accommodate the symbol rate
setting (Bit Rate = Symbols/s x Number of Bits/Symbol).
• Occupied Signal Bandwidth = Symbol Rate x (1 + Filter Alpha); therefore, the occupied signal
bandwidth is dependent on the filter alpha of the Nyquist or Root Nyquist filter being used. (To change
the filter alpha, refer to the procedure,
Nyquist Filter" on page

To Set a Symbol Rate

1. Press .
Preset
Mode Custom
2. Press >
or
Mode Custom Real Time I/Q Baseband
> >
3. Enter a new symbol rate and press

To Restore the Default Symbol Rate (Custom Real Time I/Q Only)

Mode Custom
• Press >
This replaces the current symbol rate with the default symbol rate for the selected modulation format.
Chapter 6
"Adjusting the Filter Alpha of a Predefined Root Nyquist or
126.)
ARB Waveform Generator
>
Symbol Rate
>
Msps ksps
,
Real Time I/Q Baseband
>
Digital Mod Define
> >
sps
, or .
Symbol Rate Restore Default Symbol Rate
> >
Custom Arb Waveform Generator

Working with Symbol Rates

Symbol Rate
.
133