Sign in Subscribe

DVB (digital video broadcasting)

Last updated on 

Digital Video Broadcasting (DVB) is a set of international standards that governs the digital transmission of audio and video signals over a variety of platforms, including terrestrial, cable, and satellite networks. The DVB specifications are designed to enable efficient use of bandwidth, improved video and audio quality, and support for a wide range of interactive services.

History of DVB

The development of digital video broadcasting technology began in the early 1990s. The initial aim was to create a digital replacement for the existing analog television systems, which were limited in terms of image and sound quality and were subject to interference from other electronic devices. The European Telecommunications Standards Institute (ETSI) took the lead in defining the DVB standards, and the first version of the DVB standard was published in 1994.

The first DVB services were launched in Europe in the mid-1990s, primarily as satellite broadcasts. In 1997, the DVB project became a formal organization, with the participation of broadcasters, manufacturers, and other interested parties from around the world. Since then, the DVB specifications have been updated and extended to cover new technologies and applications.

DVB Standards

The DVB standards cover a range of different technologies and applications, including:

  1. DVB-S (Digital Video Broadcasting - Satellite) DVB-S is a standard for digital satellite television broadcasting. It defines the modulation and error correction schemes used for transmission, as well as the format of the transport stream that carries the audio and video signals. DVB-S is widely used in Europe, Africa, and parts of Asia for both free-to-air and pay television services.
  2. DVB-C (Digital Video Broadcasting - Cable) DVB-C is a standard for digital cable television broadcasting. It defines the modulation and error correction schemes used for transmission, as well as the format of the transport stream that carries the audio and video signals. DVB-C is widely used in Europe and other parts of the world for both free-to-air and pay television services.
  3. DVB-T (Digital Video Broadcasting - Terrestrial) DVB-T is a standard for digital terrestrial television broadcasting. It defines the modulation and error correction schemes used for transmission, as well as the format of the transport stream that carries the audio and video signals. DVB-T is widely used in Europe, Asia, Africa, and Australia for both free-to-air and pay television services.
  4. DVB-H (Digital Video Broadcasting - Handheld) DVB-H is a standard for mobile television broadcasting. It is designed to allow the delivery of television content to handheld devices such as mobile phones and personal digital assistants (PDAs). DVB-H uses a different modulation scheme and transport stream format than other DVB standards, in order to optimize the delivery of video to small screens.
  5. DVB-T2 (Digital Video Broadcasting - Second Generation Terrestrial) DVB-T2 is an updated version of the DVB-T standard, designed to provide improved performance and support for new features such as high-definition television (HDTV) and 3D television. DVB-T2 uses more advanced modulation and error correction schemes than DVB-T, which allows for higher data rates and better reception in difficult signal environments.
  6. DVB-S2 (Digital Video Broadcasting - Second Generation Satellite) DVB-S2 is an updated version of the DVB-S standard, designed to provide improved performance and support for new features such as HDTV and interactive services. DVB-S2 uses more advanced modulation and error correction schemes than DVB-S, which allows for higher data rates and better reception in difficult signal environments.
  7. DVB-C2 (Digital Video Broadcasting - Second Generation Cable) DVB-C2 is an updated version of the DVB-C standard, designed to provide improved performance and support for new features such as HDTV and interactive services. DVB-C2 uses more advanced modulation and error correction schemes than DVB-C, which allows for higher data rates and better reception in difficult signal environments.

Transport Stream and MPEG

One of the key features of the DVB standards is the use of a transport stream to carry audio and video data. The transport stream is a multiplexed stream of data that includes the audio and video data, as well as other information such as program guides and service information. The transport stream is divided into packets of fixed length, and each packet includes a header and a payload. The header contains information about the packet, such as its type and the source of the data, while the payload contains the actual audio and video data.

The audio and video data carried in the transport stream is encoded using the MPEG (Moving Picture Experts Group) standards. MPEG is a set of compression standards that allow for efficient encoding and decoding of audio and video data. The MPEG standards define different compression schemes, known as codecs, that are used to encode and decode audio and video data. The most commonly used codecs in DVB systems are MPEG-2 and MPEG-4.

Interactive Services

Another important feature of the DVB standards is support for interactive services. Interactive services allow viewers to interact with television content in real-time, providing features such as program guides, electronic program guides (EPGs), and video-on-demand (VOD) services. Interactive services are delivered using a separate data stream, known as the data carousel, which is transmitted alongside the audio and video data.

EPGs provide viewers with information about upcoming programs, as well as program summaries and scheduling information. VOD services allow viewers to select and view specific programs on-demand, rather than having to watch programs at a fixed time. Other interactive services supported by DVB systems include interactive advertising, interactive quizzes and games, and social media integration.

Conclusion

In conclusion, DVB is a set of international standards that governs the digital transmission of audio and video signals over a variety of platforms. The DVB standards are designed to enable efficient use of bandwidth, improved video and audio quality, and support for a wide range of interactive services. The DVB standards cover a range of different technologies and applications, including satellite, cable, terrestrial, and mobile broadcasting. The use of transport streams and MPEG encoding allows for efficient transmission and decoding of audio and video data, while support for interactive services allows for a more engaging and personalized viewing experience.