FMUSER INTERNATIONAL GROUP INC.
广州市汉婷生物技术开发有限公司
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at the same symbol rate. Accordingly, with the TS coding rate increasing,
the signals’ anti-jamming capability will become weaker. Hence, those
wired network currently in effect usually adopt QAM modulation mode no
exceeding 64QAM.
What needs to be pointed out is, the effective coding rate this modulator
can transport is limitary when the device works as different constellations
and symbol rates.
User can refer to the f ormula as below:
Max_input_bitrate = Symb_rate*qam_bits*188/204
Max input bit rate: the maximum effective inputting coding rate
Symb rate: the symbol rate
Qam_bits: the QAM bit when device works as current constellation (user
can refer to the following table when device works as 6.875Msps symbol
rate):
Constellation
qam_bits
(
bit/symb
)
Symb_rate
(
Msps
)
Max_input_bitrate
(
Mbps
)
16
4
6.875
25.343
32
5
31.679
64
6
38.015
128
7
44.350
256
8
50.686
4.2.2.4 Symbol rate
After entering the submenu by pressing ENTER key, user can set the
symbol rate by moving the UP/DOW N/LEFT/RIGHT key and then
repressing ENTER to confirm.
►
1.4 Symbol Rate J.83A/DVB-C
6.875Msps
►
1.4 Symbol Rate J.83A/DVB-C
6.875Msps