DVB-T

The COFDM modulation used in the DVB-T standard splits a digital data stream into a large number of slower digital streams, each of which digitally modulates a series of closely spaced adjacent carrier frequencies. The microcircuits of devices performing modulation can work with the number of carriers equal to any power of two, so the nearest number was chosen${\displaystyle \mathrm{<span\; class="mwe-math-element"><span\; class="mwe-math-mathml-inline\; mwe-math-mathml-a11y"\; style="display:\; none;">8192</span></span>}<span\; class="mwe-math-element"><span\; class="mwe-math-mathml-inline\; mwe-math-mathml-a11y"\; style="display:\; none;">=</span></span>{\mathrm{<span\; class="mwe-math-element"><span\; class="mwe-math-mathml-inline\; mwe-math-mathml-a11y"\; style="display:\; none;">2</span></span>}}^{\mathrm{<span\; class="mwe-math-element"><span\; class="mwe-math-mathml-inline\; mwe-math-mathml-a11y"\; style="display:\; none;">13</span></span>}}}$ {\ displaystyle 8192 = 2 ^ {13}}   , the mode is called “8k”. To accelerate the adoption of the standard, the requirements for a single-frequency network were reduced, limited to the number of carriers${\displaystyle \mathrm{<span\; class="mwe-math-element"><span\; class="mwe-math-mathml-inline\; mwe-math-mathml-a11y"\; style="display:\; none;">2048</span></span>}<span\; class="mwe-math-element"><span\; class="mwe-math-mathml-inline\; mwe-math-mathml-a11y"\; style="display:\; none;">=</span></span>{\mathrm{<span\; class="mwe-math-element"><span\; class="mwe-math-mathml-inline\; mwe-math-mathml-a11y"\; style="display:\; none;">2</span></span>}}^{\mathrm{<span\; class="mwe-math-element"><span\; class="mwe-math-mathml-inline\; mwe-math-mathml-a11y"\; style="display:\; none;">eleven</span></span>}}}$ {\ displaystyle 2048 = 2 ^ {11}}   , 2k mode. As a result, a single specification “2k / 8k” was adopted. The standard uses two values ​​of the duration of the active part of the characters (T) - 224 μs for the 2k mode and 896 μs for the 8k mode. The carrier spacing is${\displaystyle \mathrm{<span\; class="mwe-math-element"><span\; class="mwe-math-mathml-inline\; mwe-math-mathml-a11y"\; style="display:\; none;">△</span></span>}\mathrm{<span\; class="mwe-math-element"><span\; class="mwe-math-mathml-inline\; mwe-math-mathml-a11y"\; style="display:\; none;">f</span></span>}<span\; class="mwe-math-element"><span\; class="mwe-math-mathml-inline\; mwe-math-mathml-a11y"\; style="display:\; none;">=</span></span>\mathrm{<span\; class="mwe-math-element"><span\; class="mwe-math-mathml-inline\; mwe-math-mathml-a11y"\; style="display:\; none;">one</span></span>}<span\; class="mwe-math-element"><span\; class="mwe-math-mathml-inline\; mwe-math-mathml-a11y"\; style="display:\; none;">/</span></span>\mathrm{<span\; class="mwe-math-element"><span\; class="mwe-math-mathml-inline\; mwe-math-mathml-a11y"\; style="display:\; none;">T</span></span>}}$ {\ displaystyle \ triangle f = 1 / T}  

4464 Hz and 1116 Hz, the number of carriers (N) 1705 and 6817, respectively.

The DVB-T standard uses QPSK , 16- QAM, or 64-QAM modulation modes.

DVB-T allows you to provide various digital services and services:

• Multi-channel multiplexing ;
• Standard definition television SDTV in aspect ratio 4: 3 and 16: 9 ;
• High Definition Television HDTV ;
• Ultra High Definition Television UHDTV ;
• 3D TV in DVB 3D-TV standard;
• Interactive hybrid television standard Hbb TV ;
• Video on demand ;
• TV guide ;
• Teletext
• Subtitles
• Stereo sound ;
• Surround sound ;
• Dolby Digital Sound;
• Multisound (choice of broadcasting language);
• Digital radio ;
• Synchronization of time and date with digital broadcasting;
• Data transmission in the DVB-DATA standard;
• Direct and reverse communication channels for interactive services in DVB-RCS and DVB-RCT standards ;
• Broadband internet access .

All digital services and DVB-T services are listed. Many digital services and services are interactive .

A digital DVB-T signal is received by an on-air collective, individual or indoor antenna connected to a TV with a built-in DVB-T decoder or to a DVB-T receiver (set-top box).

Also, the DVB-T digital signal can be received on any computer with a built-in DVB-T decoder.

Digital television in Russia began with the adoption in December 1999 of the document “The Strategy for the Transition from Analog to Digital Television Broadcasting in Russia”, and in May 2004, the Government of the Russian Federation signed an order to switch to digital broadcasting in DVB-T standard by 2015. Since 2010, the Russian Television and Radio Broadcasting Network (RTRS) began in Russia the construction of a terrestrial digital television network in the DVB-T standard, the first digital transmitters were launched in the Far East . ^[1] Now in Russia there are several private companies that provide paid services of digital terrestrial television in the DVB-T standard. On March 19, 2012, test digital broadcasting in Russia was transferred to the new DVB-T2 standard.

Terrestrial digital broadcasting in Ukraine began (in Odessa region) in test mode since September 2008; at the beginning of 2009, constant broadcasting was already provided. Since April 1, 2009 broadcasting has been carried out in Kiev, Zhytomyr, Kiev and Odessa regions. As of 05/01/2015, broadcasting in Kiev is carried out by three digital multiplexes of the DVB-T / MPEG-2 standard (eleven TV channels, transmitter power - 0.5, 1.2 and 1.5 kW, respectively).

Starting from July 1, 2005, a permanent broadcasting of a package of television and broadcasting programs in DVB-T format was started in Belarus . As of January 1, 2016, the coverage of the population of the republic with digital broadcasting of the DVB-T standard was 99.45%. On May 15, 2015, analog broadcast television in the decimeter wavelength range was completely discontinued, and on January 4, 2016 in the meter. However, the analogue television signal was retained in the cable television networks of Belarus.

In Latvia (since June 1, 2010 ) and Lithuania (since October 30, 2012 ), broadcasting is conducted only in MPEG-4 digital format.

In 2010, Uzbekistan launched digital terrestrial television using the DVB-T standard, broadcasting using the MPEG-4 AVC compression format. Broadcasting is carried out by UZDIGITAL TV , the free software package (“Basic”) includes 12 television channels.

In Germany, broadcasting in the DVB-T standard has ceased since March 30, 2017 due to the transition to the DVB-T2 HD standard ^[2] .

In Israel, a DVB-T broadcast called Digital Terrestrial Television (DTT) was launched on August 2, 2009. Currently, 5 channels can be received. Broadcasting is in MPEG-4 format. ^[3]

• DVB-T2

• B.A. Lokshin. Digital broadcasting: from studio to viewer. - M., 2000 .-- ISBN 5-88230-049-5 .
• V.A. Serov. Broadcast digital television DVB-T / H. - SPb .: BHV-Petersburg, 2010 .-- ISBN 978-5-9775-0538-3 .

• DVB-T Standard Information at ROHDE & SCHWARZ