FMUSER INTERNATIONAL GROUP INC.
广州市汉婷生物技术开发有限公司
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transport 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 formula 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
