Viavi OneExpert CATV 630, Расширенное краткое руководство по началу работы

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DOCSIS 3.1 OFDM Carrier Level Measurements
Select OFDM
carrier in scan
Look at OFDM
carrier average
level
Level approximates
6MHz QAM power,
for example, all at
10dBmV
 Measure and reference OFDM carriers in comparison to
power in a 6 MHz bandwidth (CableLabs® recommendation).
 With 8 MHz QAM in Europe  Set the OFDM level (ref. 6
MHz) 1.2 dB below the 8 MHz QAM 256 to maintain the
same power/Hz.
 PLC carrier average power will be approximately 0.8dB
higher than other carriers due to additional pilots and data
patterns
 Total OFDM carrier (up to 192MHz) power is greatly different
than average power in a 6 MHz bandwidth:
 For a 96 MHz wide OFDM carrier, the total power will be 12.04 dB higher.
 For a 192 MHz wide OFDM carrier, the total power will be 15.05 dB higher
 Do not use the total OFDM power to adjust CMTS output
power: this would be like using total integrated power of 32
DOCSIS QAM carriers to set level.