User`s guide

Agilent X-Series Signal Generators User’s Guide 367
Custom Digital Modulation (Option 431)
Differential Encoding
This loads a default 4QAM I/Q modulation and displays it in the I/Q table editor.
The default 4QAM I/Q modulation contains data that represent 4 symbols (00, 01, 10, and 11)
mapped into the I/Q plane using 2 distinct values (1.000000 and −1.000000). These 4 symbols will be
traversed during the modulation process by the symbol table offset values associated with each
symbol of data. Refer to Figure 13- 41.
Figure 13-41
Accessing the Differential State Map Table Editor
Press Configure Differential Encoding.
This opens the Differential State Map table editor, as shown. At this point, you see the data for
the 1st symbol (00000000) and the cursor prepared to accept an offset value.You are now prepared to
create a custom differential encoding for the user–defined default 4QAM I/Q modulation. Refer to
Figure 13- 42 on page 367.
Figure 13-42
Data
Symbol Table Offset Values Entry Area