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DVB-H Technology

The DVB-H standard EN 302 304 specifies a transmission system that provides an efficient way of carrying multimedia services over digital terrestrial broadcasting networks to handheld terminals. It uses various ETSI digital video broadcasting standards, identifying functionalities and parameters to be implemented in order to deliver DVB-H-compliant services.

Specific requirements for the DVB-H system are:

  • As a battery-powered system, the transmission system must make it possible to repeatedly power off some parts of the reception chain to increase the battery duration.
  • By targeting nomadic users, the transmission system must ease access to the DVB-H services when receivers leave a given transmission cell and enter a new one.
  • Since it is expected to serve various situations of use (indoor and outdoor use, pedestrian use, and use inside moving vehicles), the transmission system must offer enough flexibility/scalability to allow the reception of DVB-H services at various speeds, while optimizing transmitter coverage.
  • As services are expected to be delivered in an environment suffering high levels of man-made noise, the transmission system must offer the means to mitigate their effects on the receiving capabilities.
  • Since DVB-H aims to provide a generic way to serve handheld terminals in various part of the world, the transmission system must offer the flexibility to be used in various transmission bands and channel bandwidths.

A full DVB-H system is defined by combining elements in the physical and link layers as well as service information. It makes use of the following technology elements for the link layer and the physical layer:

Link Layer:

  • Time-slicing in order to reduce the average power consumption of the terminal and to enable smooth and seamless frequency handover.
  • Time-slicing in order to reduce the average power consumption of the terminal and to enable smooth and seamless frequency handover.
  • Forward error correction for multiprotocol encapsulated data (MPE-FEC) for an improvement in C/N performance and Doppler performance in mobile channels, also improving tolerance to impulse interference.

Physical layer (included in the DVB-T standard EN 300 744):

  • DVB-H signaling in the TPS bits to enhance and speed up service discovery; cell identifier is also carried on TPS bits to support quicker signal scan and frequency handover on mobile receivers.
  • 4K mode for trading off mobility and SFN cell size, allowing single antenna reception in medium SFNs at very high speed, thus adding flexibility in the network design.
  • In-depth symbol interleaver for the 2K and 4K modes for further improving their robustness in mobile environment and impulse noise conditions.

It is also important to note that the payload of DVB-H consists of IP datagrams or other network layer datagrams encapsulated into MPE sections.

See also EN 300 744 (DVB-T standard) for DVB-H-related amendments.

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