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DVB-SH Technology

The DVB-SH standard EN 302 583 specifies a transmission system for hybrid satellite and terrestrial digital television broadcasting to mobile terminals. It is derived from the DVB-T, DVB-H, and DVB-S2 system specifications. The purpose of the DVB-SH standard is to provide an efficient transmission system using frequencies below 3 GHz suitable for satellite services to handheld devices with a focus on reception threshold and resistance to mobile satellite channel impairments.

The system relies on a hybrid satellite/terrestrial infrastructure. The signals are broadcast to mobile terminals on two paths:

  • A direct path from a broadcast station to the terminals via the satellite.
  • An indirect path from a broadcast station to terminals via terrestrial repeaters that form the complementary ground component (CGC) to the satellite. The CGC can be fed through satellite and/or terrestrial distribution networks.

The system includes two transmission modes:

  • An OFDM mode (SH-A) based on the DVB-T standard with specific enhancements. This mode can be used on both the direct and indirect paths; the two signals are combined in the receiver to strengthen the reception in an SFN configuration.
  • A TDM mode (SH-B) partly derived from the DVB-S2 standard in order to optimize transmission through a satellite toward mobile terminals. This mode is used on the direct path only.

The system supports code diversity recombination between satellite TDM and terrestrial OFDM modes so as to increase the robustness of the transmission in relevant areas. The DVB-SH standard specifies the digital signal format and the digital signal modulation and coding in order to allow compatibility between pieces of equipment developed by different manufacturers. Signal processing on the modulator end is described in detail, while processing on the receiver end is left open to individual implementation.

DVB-SH Deployment Scenario

Initial field trials were conducted in 2008. No satellites were available at the time of the trials. In 2009, one satellite initiated service for this technology and provide Europe with coverage.

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