Digital television for SA


The test signal familiar to viewers who
remember the early days of South African
television. This analogue technology will
soon be replaced by digital television.

Janine Erasmus

South Africa is awaiting the advent of digital terrestrial television (DTT), which will see a migration from the current analogue system to digital broadcasting. The changeover, estimated at R7-billion ($887 232), is being driven by the Policy Development Branch of the national Department of Communications in collaboration with state-owned broadcast network operator Sentech.

The migration is steered by the Digital Broadcasting Migration working group, which comprises four committees dealing with content, technical matters, economics and policy. It was established in August 2005 by Minister of Communications Ivy Matsepe-Casaburri with the mandate to develop a national strategy for the analogue to digital migration.

The working group consists of representatives from the broadcasting industry, the Independent Communications Authority of South Africa, government, civil society, organised labour, and relevant consumer groups. The group presented its recommendations in a report to the minister in November 2006.

“Digital migration was mooted as early as the late 1990s in South Africa,” said Matsepe-Casaburri at the handover. “Through technological transformation, digital broadcasting can deliver more benefits for the industry and the public, with reduced transmission costs in the long term. As government, we have an obligation to ensure that services reach every citizen of this country at an even more affordable rate.”

Since then the Department of Communications has been working on a national migration policy to ensure that the roll-out progresses smoothly across the country and that all stakeholders are fully informed about what is required for a successful implementation.

Upgrading existing infrastructure

Sentech is overseeing the necessary infrastructure requirements. The upgrade process entails the conversion of 184 existing analogue sites to digital capability.

The bulk of the service will be rolled out over two years from the first switch-on which is scheduled for November 2008, while broadcasts of analogue signal are expected to cease completely around 2015. With a number of delays in the finalisation of the digital migration policy, however, it is unclear if this deadline will be met.

Sentech has been conducting limited DTT broadcasts in advance of the anticipated switch-on, commencing test transmissions from its main broadcast site in Johannesburg in March 2006. The company plans to have most of South Africa ready for digital broadcasts of the 2010 Fifa World Cup, and also plans to transmit key games and the tournament final via a High Definition signal.

According to Sentech, “The first phase of DTT switch-on will entail the country’s main metropolitan areas with the second phase earmarked for completion before 2010. By that time at least 78% of the country’s population will have access to DTT services.”

During the initial phase, viewers who do not own digital televisions will have time to purchase the necessary DTT receiving equipment as analogue and digital broadcasting will run side by side for three years.

Making the move to digital

Television in South Africa was introduced only in 1976, with no major upgrade of infrastructure since that time. The country was one of the last on the continent to introduce television, despite being one of the most technologically advanced. The reason for this is that the apartheid government of the time considered television to be a threat to its regime and to the Afrikaans language.

Initially there was only one channel which broadcast equally in English and Afrikaans, with a second introduced in 1981, broadcasting in African languages such as isiZulu, isiXhosa and seSotho.

The pay channel M-Net, backed by a consortium of newspaper publishers, came online in 1986 but was not allowed to air any news programmes as these were the domain of the state-owned South African Broadcasting Corporation. In 1998 privately-owned free-to-air channel commenced operations, offering viewers the first independent local televised news service.

All these broadcasters utilise analogue technology. The Department of Communications has named a number of reasons for the change to digital technology. One pressing reason is that South Africa is affiliated with international bodies such as the International Telecommunications Union, which has decreed a deadline of June 2015 for the Africa and Europe regions to have made the transition to digital broadcasting.

As part of the global community, the country also needs to keep up with technology standards. Analogue broadcasting technology is close to being considered obsolete, says the Department of Communications, with no new technology being developed and maintenance parts becoming scarcer. Such systems will eventually become prohibitively expensive to maintain.

The majority of South Africans use analogue televisions, so a set top box decoder is required for them to receive a digital signal. Viewers must purchase this device themselves although it is expected that government will subsidise the cost of an entry-level box to help viewers accept the change in technology.

The benefits of digital

In South Africa, Digital Terrestrial Television is the technology of choice, which means that viewers will use an antenna to receive their signal. Other countries use different methods of reception such as digital cable or digital satellite. Additionally, alternative technologies such as microwave transmission, the open internet using peer-to-peer software, or Internet Protocol Television, are all employed in various parts of the world.

Switching to digital technology will result in more efficient use of the radio frequency spectrum. For DTT technology, the main advantages are a greater number of channels; better audio and video quality; possibility of broadcasting via a variety of platforms including mobile phones and internet; and simultaneous transmission of different streams such as video, audio, data and voice.

Digital television enables broadcasters to transmit multiple channels of programming at the same time – this is called multicasting – whereas analogue technology only permits the transmission of one channel at a time, which is also more susceptible to interference and degradation of the signal.

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