SVP UDT-4K, Руководство пользователя

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UDT-4K UHD HEVC Digital Camera Transmitter
MANUAL V0
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Annex C: Modulation Standards
This chapter describes the DVB-T/T2 and DVB-S/S2 standards, as well as
their features and the differences between them.
C.1 DVB-T
DVB-T is a technical standard that specifies the framing
structure, channel coding and modulation for digital terrestrial
television (DTT) broadcasting. It is a flexible system that
allows networks to be designed for the delivery of a wide range of services,
from HDTV to multichannel SDTV, fixed, portable, mobile, and even handheld
reception.
C.1.1 How Does It Work
DVB-T, in common with almost all modern terrestrial transmission systems,
uses OFDM (orthogonal frequency division multiplex) modulation. This type
of modulation, which uses a large number of sub-carriers, delivers a robust
signal that has the ability to deal with very severe channel conditions.
DVB-T has technical characteristics that make it a very flexible system:
•
3 modulation options (QPSK, 16QAM, 64QAM).
•
5 different FEC (forward error correction) rates.
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4 Guard Intervals.
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Choice of 2k or 8k carriers.
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Can operate in 6, 7 or 8MHz channel bandwidths.
Using different combinations of the above parameters a DVB-T network can
be designed to match the requirements of the network operator, finding the
right balance between robustness and capacity.