DekTec DTC-379 C2Xpress - Manual (Page 10)

© 2010 - 2015 DekTec Digital Video BV Page 10/18 DTC-379 C2Xpress Manual
Essential Tools for Digital-TV Professionals February 2015
DTC-379 C2Xpress
7.5. Output settings
This area allows you to specify the output settings. Dependant on the selected output format, other
selection fields are shown in this area.
- Format
Format Description
I/Q Float32 Pairs of 32-bit floats in I, Q order
I/Q Int16 Pairs of signed 16-bit integers in I, Q order, little Endian:
Byte #0: Least-significant byte I
Byte #1: Most-significant byte I
Byte #2: Least-significant byte Q
Byte #3: Most-significant byte Q
Etc.
I/Q Text Text (ASCII)-based format consisting of pairs of four-character hexadecimal
values with 0x prefix in I, Q order. The I and Q values are separated by a
TAB and I/Q pairs are separated by a linefeed.
Example:
0x2b45<TAB>0x1c3f<LF>
0xfeA9<TAB>0x0073<LF>
RF DVB-C2 RF output through the selected DVB-C2 modulator port
7.5.1. I/Q Output Settings
In case the output type I/Q samples is selected (I/Q Float32, I/Q Int16 or I/Q Text), this area allows
the selection of the location and the base name of the generated I/Q sample file and test point data
files.
I/Q samples file settings
- #Frames
The number of C2 frames to be generated. The resulting file length and size are displayed.
- Append files
If not checked, C2Xpress overwrites the previously generated file. If checked, the C2Xpress
appends the new generated data to the end of the existing file. In combination with the “L1
change” option it allows you to create IQ-files with dynamically changing DVB-C2 paramters.
- Freq. offset
Output frequency offset by means of the distance in number of carriers from the start frequency
of the C2 System. The offset must be a multiple of the carrier spacing.
This option in combination with the output bandwidth allows you to generate a part of the
spectrum of the C2 System, starting at ‘start frequency’ + ’output frequency offset’ and ending at
‘start frequency’ + ’output frequency offset’ + ‘output bandwidth’.