DVB-H

REMORA Category: D


Digital Video Broadcasting-Handheld (DVB-H) is an open standard developed by the DVB Project with the aim of delivering television and multimedia content to mobile handheld devices, such as mobile phones and PDAs. DVB-H is derived from the DVB-T standard, which is used for terrestrial broadcasting. To optimize power consumption for mobile reception, DVB-H employs a technique called time slicing. This means that specific content is transmitted at scheduled time intervals. This approach allows handheld devices to be activated only during these transmission bursts, conserving power and improving error correction and mobility. However, it can introduce noticeable delays when users switch between channels.

Key features and considerations of DVB-H include:

  1. Time Slicing: DVB-H uses time slicing to reduce power consumption, enabling devices to operate only during specific transmission intervals. This approach enhances power efficiency and mobility.
  2. Derived from DVB-T: DVB-H is based on the DVB-T standard, making it compatible with existing DVB-T networks. This compatibility simplifies the implementation of DVB-H within established broadcasting infrastructures.
  3. COFDM Mode: DVB-H introduces a new COFDM (Coded Orthogonal Frequency Division Multiplexing) mode known as 4k mode, which uses 3409 carriers. While this mode offers improved error correction, the net bit rate is lower than DVB-T due to the additional error correction overhead. The maximum bit rate for DVB-H is approximately 15 Mbit/s.
  4. IP Datacast: Content delivery in DVB-H is based on IP datacast, which facilitates integration with mobile networks. This integration allows for seamless content delivery and interaction with mobile services.
  5. Spectrum Usage: DVB-H can theoretically be used within existing broadcasting bands, including VHF Band III (174 – 230 MHz) and UHF Band IV/Band V (470 – 862 MHz), using standard 5, 6, 7, or 8 MHz channel bandwidths. However, there are certain constraints to consider:
    • Band III offers good signal propagation but requires longer receiving antennas, which may not be suitable for handheld devices.
    • Band IV and V have acceptable coverage characteristics, and antenna size is suitable for integration. However, interference from GSM900 transmission in the upper part of Band V could be a concern.
    • An alternative is to use L-band spectrum (around 1.5 GHz), but this may pose challenges related to indoor reception and potential interference from GSM1800 transmission.

Overall, DVB-H is designed to provide a platform for efficient and mobile-centric broadcasting of television and multimedia content, making it suitable for handheld devices. Its use of time slicing and integration with IP datacast contribute to its power efficiency and compatibility with mobile networks. However, considerations regarding spectrum usage and potential interference must be taken into account when implementing DVB-H.