Our country fully switched to digital television in 2019. It has a number of advantages over analogue television. For consumers it is a wider choice of programs and services, better quality, interactivity, the possibility of delayed viewing and parental control. For operators and broadcasters - increased spectral and energy efficiency of terrestrial broadcasting networks, reduced operating costs and convenience in organizing digital archives.
This year two national standards for digital broadcasting television were accepted.
GOST R 58912-2020, Digital video broadcasting. Second generation of digital terrestrial television broadcasting system DVB-T2. General technical requirements, is going to be introduced for the first time in January 2021.
The system, which is covered by the standard, is a set of equipment that provides delivery of television programs to the consumer via radio channels of distribution networks by using ground transmission centers.
The document establishes the general description, structure and main parameters of this system; requirements to interfaces and screen elements; parameters of through transmission of digital television signal over terrestrial network of terrestrial digital television broadcasting and over transmission trunk lines, including broadcast objects and methods of measuring characteristics and parameters of initial and delivered digital television signal to broadcast objects.
According to the standard, the DVB-T2 system must be able to encode, multiplex, transmit and receive video signals, audio signals, multimedia programs, additional and auxiliary data, service information in the broadcast multiplexes.
GOST R 58798-2020, Digital video broadcasting. The receivers for terrestrial digital TV broadcasting DVB-T2 with the support of the HEVC video compression standard. The basic parameters, was put into into force for the first time in August 2020.
According to I.N. Krasnoselsky, the Head of Laboratory of Federal State Unitary Enterprise Radio Research and Development Institute "NIIR" - "receivers, which are covered by the document, are the most important elements of the digital broadcasting network". The complexity and quality of the underlying circuitry, demodulation, decoding, formation (rendering) of reproduced images and sound signals depend on the visual and sound picture that will be available to the user.
"Modern and especially promising encoding algorithms are capable of providing the user with the highest quality programs, including UHD images with a large dynamic range and extended color gamut, with multi-channel immersive sound. The variety of image and sound compression algorithms dictates the use of multi-standard decoders in receivers. The most advanced television receivers are able to display the created programs in their full quality. On the other hand, not all viewers have advanced equipment, or not all viewers want to receive programs with maximum quality. Therefore, a digital receiver must be able to output programs with the quality specified by the user or according to the technical capabilities of the equipment available to the user. For example, convert the signal of high definition images into images of standard definition or vice versa (there are such algorithms), convert multi-channel sound into stereo sound.
National Standard GOST R 58798-2020 just sets possible options for encoding/decoding algorithms of digital streams transmitted to the consumer, and those methods of processing them in the receiver and signaling about the presentation formats, as well as the possibilities of their transformation, which will allow to reproduce programs in any case, but with the quality that takes into account existing or given restrictions, "- explained I.N. Krasnoselsky.
The specificity of the national standards GOST R 58798-2020 and GOST R 58912-2020 is that they introduce technical requirements corresponding to the most advanced to date European system of digital terrestrial television broadcasting DVB-T2 and the whole range of international compression standards (MPEG-2, H.264/AVC, H.265/HEVC) with support of standard, high and ultra-high definition images. Including UHD image options with high dynamic range (HDR) and high frame rate (HFR).
"GOST R 58798-2020 and GOST R 58912-2020 establish the technological leadership of Russia in the field of telecommunications and information technologies as applied to the digital broadcasting industry. This promotes the integration of our country into the world economy and international systems of standardization of digital television as an equal partner and sets standards for the development of the television industry for the future", - concluded the Expert.
For reference:
DVB-T2 is a European system of second generation digital terrestrial (terrestrial) television broadcasting (i.e. with improved characteristics). This system is put into operation in the Russian Federation, and it is used to broadcast two publicly available multiplexes of 10 digital television programs each.
HEVC or H.265 is a new standard for reducing the redundancy (compression) of the original digital signals of television programs. It is particularly effective for encoding high definition and ultra-high definition images.