Agilent Technologies E8247C, Руководство пользователя

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Chapter 7 147
Custom Real Time I/Q Baseband
Working with Data Patterns
Working with Data Patterns
This section provides information on the following:
• “Using a Predefined Data Pattern” on page 148
• “Using a User-Defined Data Pattern” on page 149
• “Using an Externally Supplied Data Pattern” on page 152
The Data menu enables you to select from predefined and user defined data patterns. Data Patterns are used
for transmitting continuous streams of unframed data. When the Custom Off On softkey is on, the real-time
custom I/Q symbol builder creates I/Q symbols based on the data pattern and modulation type that has been
selected. Refer to
“Working with Modulation Types” on page 136 for information on selecting a modulation
type.
The following data patterns are available:
• PN sequence allows you to access a menu (PN9, PN11, PN15, PN20, PN23) for internal data generation
of pseudorandom sequences (pseudorandom noise sequences); a pseudorandom noise sequence is a
periodic binary sequence approximating, in some sense, a Bernoulli “coin tossing” process with
equiprobable outcomes.
• FIX4 0000 allows you to define a 4-bit repeating sequence data pattern and make it the active function.
The selected 4-bit pattern will be repeated as necessary to provide a continuous stream of data.
• Other Patterns allows you to access a menu of choices (4 1’s & 4 0’s, 8 1’s & 8 0’s, 16 1’s & 16 0’s, 32
1’s & 32 0’s, or 64 1’s & 64 0’s) from which you can select a data pattern. Each pattern contains an equal
number of ones and zeroes. The selected pattern will be repeated as necessary to provide a continuous
stream of data.
• User File allows you to access a menu of choices from which you can create a file and store it to the
Catalog of Bit Files, select from a Catalog of Bit Files and use it, or select from a Catalog of Bit Files,
edit the file, and resave the file.
• Ext allows data patterns to be fed into the I/Q symbol builder, through the DATA port, in real-time.