Отчет мсэ-r bt. 2140-1 (05/2009)



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12 Republic of Korea


The Republic of Korea decided digital transition from analogue broadcasting services to provide spectrum efficient and high quality services. With careful studies and field test, standards to achieve effectively the digital transition of each analogue media were chosen. For fixed reception at home, high quality services on large screen display will be major service models but low or intermediate quality acceptable on small and handheld receivers for mobile reception.

In the Republic of Korea, digital terrestrial television broadcasting was started in 2001, digital satellite broadcasting in 2002, and terrestrial multimedia broadcasting in 2005. Cable TV is also in service of digital programs since 2002.


12.1 Digital TV for fixed reception


Terrestrial television sets may be appropriate receivers to enjoy high definition video and multi-channel audio with a large screen at home. The Republic of Korea adopted ATSC system in 1997 for digital transition of analogue television broadcasting in the UHF band according to the policy to obtain high definition quality within 6 MHz raster and conducted field tests in 1999 and 2000.

There are 160 ATSC transmitters currently installed around the country covering about 92% of territory as of 2006. Several principles were given to digital terrestrial television broadcasters to follow government policies on digital transition as follows:

Simulcast of analogue and digital broadcasting until analogue switchover

Requirement of minimum time for HDTV programs (annually increasing)

Return of frequencies allocated to analogue television stations

It was not an easy job to find frequencies for digital television stations, because the UHF band from 470


752 MHz is already occupied with analogue television broadcasting. Hence, the band of 752806, currently allocated to fixed and mobile services in Korea, was decided to use for broadcasting services during the transition time only, but these bands will be returned after analogue switchover. In order to facilitate frequency assignments, Equalization Digital On-Channel Repeater and Distributed Translator are devised for ATSC system to use same frequencies.

More than 4 million Set-Top-Boxes, about 23% of households, were sold as of 2006. It is expected to increase penetration rates of Set-Top-Boxes, since data broadcasting was started in 2005. Data services provide information on dramas or records of sports games as well as EPG.


12.2 T-DMB for mobile reception


For mobile multimedia broadcasting service, the Republic of Korea developed the video standard, which is fully backward compatible with the T-DAB, and named as Terrestrial Digital Multimedia Broadcasting
(T-DMB). The specification of T-DMB was standardized as ETSI TS102 427 and ETSI TS 102 428 and submitted to WP 6M for a new recommendation of mobile multimedia broadcasting by handheld receivers.

T-DMB pilot services were conducted in Band III in Seoul metropolitan area and its vicinity and field test results showed good mobile reception quality. Field test results were submitted to 6M meeting held in April 2004 and included in the Report ITU-R BT.2049 (see also Doc. 6E/186).

In December 2005, the Republic of Korea launched commercial service of T-DMB in Seoul Metropolitan area and expanded to the nationwide services in March 2007. Each broadcaster provides two video services or one video with three audio services within an ensemble and optionally with data services.

The whole territory was divided into seven regions including Jeju Island for business. One national broadcaster and seventeen regional broadcasters were licensed to serve T-DMB nationIIde. It was intInded to serve each region with the same frequency and most transmitters are linked with Single Frequency Networks to cover the wanted regional area. Fortunately, Seoul Metropolitan area is assigned two TV channels, 8 and 12, and served by six broadcasters. In order to allocate frequencies to T-DMB stations, frequencies of 44 analogue TVR in the band III were changed after simulation of mutual interference and analysis. The channel assignment plan in the Band III for the services is shown in Fig. 64.

FIGURE 64

Channel Assignments for T-DMB in Korea



채널현황_24비트
However some transmitters in southern part do not have same frequencies due to pre-occupied frequencies for analogue TV stations and some regions consist of Multi Frequency Networks; Channel 7 and Channel 8 of the south-western region, Channel 7 and Channel 9 of the middle of eastern region, Channel 9 and Channel 12 of south-eastern region and Channel 8 and Channel 12 of Jeju Island. Hand-over technology was implemented on receivers for continued reception of a wanted service, even in other ensembles or different RF channels, while moving into other network.

In order to enjoy T-DMB services even underground, low powered T-DMB gap-fillers, which receive outdoor T-DMB signals and retransmit, were installed at 294 points to cover the whole lines of Metros in Seoul.

A variety of commercial receivers for portable or handheld reception are introduced in the market. Since the launch of T-DMB service in December 2005, 3.14 million receivers are sold in Korea as of 31 January 2007.

Data services such as EPG, TPEG and BWS are in services and interactive services using return channel will be appeared soon with the cooperation of telecommunication operators. These data services are expected to produce pay services for business by providing information on traffic jam, stock and even Internet access.


13 Venezuela


Adoption of standards for digital sound and digital television in Venezuela

Introduction

In order to assist in the selection of Digital Radio and Television systems in Venezuela, the National Commission of Telecommunications (CONATEL) has created a Digital Radio and Television project, supported by constant research. Its ultimate goal is advancing the tasks for the introduction of this service, and thus, making Digital Radio and Television systems in Venezuela a medium-term reality.

Digital Radio and Television project – Development stages

The development of the Digital Radio and Television project involves four (4) stages, as described below:

Stage 1: Feasibility study (technical, economic and legal aspects)

The tasks that comprised the feasibility study –still under development- are the following:

Review of national television and radio stations regarding location, frequency, service quality, technology and regulatory aspects.

Review of digital radio and television technology development, equipment suppliers, costs, comparison and selection of the most suitable technology.

Detailed study of the band frequencies that are to be assigned to analog and digital radio and television stations, with the purpose of optimizing the use of spectrum.

Study of the required investments, economic impact and investment recuperation involved in the switching from analogical to digital radio and television systems.

Evaluation of foreign experiences regarding this matter, and possible variables for the acceptance of this technology in Venezuela.

Documental analysis of digital radio and television regulations.



Stage 2: Forum and operating tables

During this stage, contacts are made with companies in charged of the development of digital radio and television standards, as well as with equipment suppliers and regulation departments, with the cooperation of domestic radio and television operators.



Stage 3: Trials

Trials help to adopt suitable policies to benefit Venezuela’s technological smooth switch to digital radio and television. This stage will produce both experimental and regulating experiences:



Trials

Switch to the digital system.

Setting of regulation framework.

In general, domestic and foreign investments for the development of new technologies require a regulation framework, which will settle the rules for their evolution and put into practice.

The efficient performance of the above-mentioned functions will be a key aspect to plan legally sustained trials for digital radio and television systems, which can prove trustful and safe for both domestic and foreign investors. Besides, this option will facilitate the study of spectrum shares, not assigned to digital radio and television.

Other important legal aspects relate to the obligation to mention the specific spectrum share to be used by the incumbent. This share can only be used and exploited within the specific cover indicated on a special permission.

Besides, getting a special permission will not grant expectations of rights to incumbents or preferential rights whatsoever in getting of a grant for the use and exploitation of the spectrum share necessary for developing all the activities foreseen by the regulations. Once a special permission has expired, its incumbent will not be able to continue using the spectrum shares assigned, unless they update their permission.

Incumbents with special permission will not obtain any counter-payment from users because of service rendering during trials. Once the trial is over, they should present a detailed report about the activities carried out and the results obtained. At any given moment, CONATEL can inspect or supervise the trials.

For the special permission, the interested incumbents will have to indicate the accurate date for the beginning of trials and the length the trials (up to three months).

If there are justifiable reasons, the beginning of trials can be adjourned unless decided otherwise by CONATEL. The trials can only be adjourned once.

During the deliberation period, CONATEL can require any concerning information from the incumbents, in order to evaluate the application. In this case, CONATEL will notify the titular that they have 10 days to submit their requirements. From the date of the application, CONATEL can interrupt the deliberation period for ten days. Due to the complexity of the matter, this period can be extended up to fifteen continuous days.

Stage 4: Standards adoption

This stage is the milestone for the digital radio and television adoption process. The fitting of the legislation in force to the characteristics of the chosen system will provide strength and trust to the process of putting digital radio and television services into practice in Venezuela.




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