Digital Video Broadcasting (DVB) is a set of standards that define digital broadcasting using existing satellite, cable, and terrestrial infrastructures.

More broadcasting services can be accommodated

With the analogue broadcasting technology, only one television service could be delivered on a single frequency or a single network of transmitters (for national coverage of the television service).

If we take the example of the UHF television band which has four frequencies per site and therefore can support four national coverage networks, this means only four analogue television services of national coverage could be provided.

However, the digital technology can carry, on average, twenty television services on a single frequency or on a single transmitter network (for national coverage of the services). The four UHF digital networks would therefore be capable of delivering eighty television services of national coverage.

Savings in infrastructure cost

Continuing with the UHF band example, with the analogue technology the four analogue television services would require a transmitter network each for national coverage of the services. In the digital domain, these four services can easily be carried by one digital transmitter network without even filling the full capacity of that one network alone.

The four analogue services would require four transmitters per site for forty-eight sites whereas the digital network would require only one transmitter per site. This points at significant savings in transmission infrastructure costs.

New broadcasting business models

The service capacity generated by the digital broadcasting technology creates an opportunity for new broadcasting business models to be realized. Whereas the analogue broadcasting technology was mainly associated with free-to-air broadcasting services, the capacity generated by the digital technology allows for the packaging of services (channels) which can be accessed on a subscription basis.

A subscription based service is a reality with the terrestrial digital technology, in the same way that such services have, hitherto, been provided via satellite transmission.

Improved coverage quality

Analogue television services degrade in picture quality the further away the television set is located from the transmitter. This progressive degradation results in showers, loss of color, poor sound quality and ghosting, the further the television set is located from the transmitter.

With the digital technology, picture and sound quality is the same throughout the transmitter’s coverage area, whether the receiver is sitting right next to the transmitter or right at the last point where an appropriate signal level is received.

This allows viewers to receive the best and the same picture quality throughout the coverage area of the transmitter, without any variation in terms of the quality. The only drawback is that picture failure is rapid beyond the threshold of reception.

Better picture and sound quality

The digital technology supports picture resolutions much higher than those of its analogue counter part. This, coupled with what is called progressive scanning, results in much better picture definition and, therefore, picture quality. High Definition and Three Dimension Television (3D TV) are supported by this platform.

Work has already started on standardizing even higher picture definition formats (Ultra High Definition) such as 4K and 8K, which provide even better picture resolution through the digital platform. Excellent sound quality, surround sound and the use of multiple languages on a programme are all possible features of the digital broadcasting technology.

Mobile broadcasting can be introduced

Apart from delivering television services to fixed receivers, mainly to television sets in the home, the digital technology allows for delivery of service to receivers in motion (in a car, bus, or train) and to portable devices such as cell-phones, tablets and laptops.

The analogue technology had difficulty in addressing these reception environments due to its failure to cope with motion, signal reflections and electrical noise.

Provision of value added services

Unlike the analogue broadcasting technology, the digital broadcasting technology is not limited to the delivery of television programmes only. Value added and interactive services such as Electronic Programme Guides, television shopping, weather forecasts, electronic newspapers etc can also be accessed on the television set by the viewer, ushering in a new television viewing experience.

Consumer benefits

The consumer benefits from digital switchover are widely recognized. Compared to analogue broadcasting, Digital Broadcasting delivers a variety of benefits including:

• Wider choice of programming and services (including additional channels, HD offerings, radio, data services, pay programmes)
• Better quality – less likely to experience signal interference and picture quality issues.