communication line and system productivity when transmitting multi-media
information.
3.
Analysis of the signal processing process in DVB-T2 standard.
The new DVB-T2 standard is improved and it is functionally advanced follower
of DVB-T standard, but DVB-T2 has each step enhanced [3] for converting the signal.
Therefore particularly interesting is to analyze the standard DVB-T2 and offer the
introduction of using it in a two-way communication line, while the DVB-T2 standard
is a technology with a one-way transmission, which assembled the modern sets of
modulation and coding combinations.
The most important differences DVB-T2 has in comparison with the classical
DVB-T standard:
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increased the number of carriers for 27265 (32K mode);
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went away of the classical coding schemes (convolutional code and Reed-
Solomon code), what replaced by the LDPC (Low-density parity-check code)
and BCH (Bose-Chaudhuri-Hocquenghem) codes;
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added a new modulation mode 256QAM;
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more "economical" transfer of service information.
Fig. 2 shows a general signal processing circuit, transmitted in DVB-T2 system.
Figure 2. The overall signal processing circuit transmitted in DVB-T2 system
Source: [4]
The principal feature of the DVB-T2 standard – the mechanism of antinoise
coding. It uses the concatenated code as a correcting code [12-13]. BCH encoder is
used as an outer code block. Code with a low density parity check (LDPC) is used as
an internal code. Before modulation (except for BPSK and QPSK) code words are
subjected to bit-interleaving and distributed to modulation symbols.
Also, a new 256-QAM modulation was added to the DVB-T2, which increases
the throughputof the transmission channel by 33% compared with the 64-QAM
modulation in DVB-T. Typically, the transition from 64-QAM to 256-QAM requires
increasing the SNR by 4-5 dB. Through the use of correcting BCH codes and LDPC,
where the efficiency is much higher than traditional error correction code (including a
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