![Agilent Technologies ESG series Скачать руководство пользователя страница 39](http://html.mh-extra.com/html/agilent-technologies/esg-series/esg-series_user-and-programming-manual_2867455039.webp)
Real-Time I/Q Baseband Generator User’s and Programming Guide
2-11
HP ESG Family Signal Generators
Using Functions
Options UN8 and 202
Mapping Custom Differential Encoding
Mapping Custom Differential Encoding
Differential encoding is a digital-encoding technique that denotes a binary value by a
signal change rather than a particular signal state. The signal generator has an editor that
enables you to manipulate the differential state map associated with user-defined I/Q and
user-defined FSK modulations. Using differential encoding, you can encode binary data
encoded during the modulation process via transitions between states defined in the
symbol table. Once you configure the differential encoding, you can activate and apply it to
the current user-defined modulation.
NOTE
For more details, see “
Understanding Differential Encoding
Creating a User-Defined I/Q Modulation
Before you design a custom differential encoding scheme, you must first create a
user-defined I/Q or FSK modulation. For the purposes of this example, you will create a
user-defined 4QAM I/Q modulation from the signal generator’s list of default I/Q maps.
1. Press
Mode
>
Real Time I/Q Base Band
(if it appears) >
Custom
>
Modulation Type
>
Define User I/Q
>
More (1 of 2)
>
Load Default I/Q Map
>
QAM
>
4QAM
Other Formats:
Mode
>
Real Time I/Q Base Band
(if it appears) >
TDMA
>
desired format
>
More (1 of 2)
>
Modify Standard
>
Modulation Type
>
Define User I/Q
>
More (1 of 2)
>
Load Default I/Q Map
>
QAM
>
4QAM
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.
Содержание ESG series
Страница 2: ...ii ...
Страница 446: ...I 16 Index Index ...