Deviser DS2831 - Chapter 8: Digital Signal Measurement

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Part II: Settings and Measurements
Chapter 8: Digital Signal Measurement
DVB-C QAM analysis functions include the following channel measurements:
• Constellation diagram • MER & BER statistics analysis
• Channel power • EVS (Error vector spectrum)
• Equalizer coefficient display and distance to fault • Simultaneous spectrum & channel scan
• In-band frequency response • Digital channel SNR
• In-band group delay • Digital Hum
Parameter Settings
The DS2831’s DVB-C analysis function is fully automated, except for a few simple parameters like frequency.
All other parameters are acquired automatically (but may still be manually adjusted at the user’s wish).
Adjustable parameters and range of the DVB-C function of the DS2831 are as follows.
Parameter
Key
Value Range
Channel number
CH
All active channels in the active channel plan
Center frequency
FREQ
5~1200 MHz
Channel bandwidth
BW
1~50 MHz
Modulation mode MODE
J.83A / C:
16 / 32 /
64 / 128 / 256 QAM
J.83B:
64 / 256 QAM
Symbol Rate (MS/s) SR
J.83A / B / C:
4~7 MS/s, self
-
adaptive
J.83D:
Fixed at 10.762 MS/s
DVB
-
C Standard
STD
J.83A, B, & C, self
-
adaptive
(J.83D by option only)
Interleave Depth
(n/a)
Self
-
adaptive only. Sett
ing is displayed in status bar.
Relevant Icons
QAM signal losing lock
QAM signal lock
Interleave depth of the I & J signals