scope:

The present document specifies a transmission system for hybrid satellite and terrestrial digital television broadcasting to mobile terminals. It is derived from the DVB-T [1] and DVB-H [6] system specification, respectively designed for digital television terrestrial broadcasting towards fixed and mobile terminals and DVB-S2, [2] designed for digital satellite broadcasting towards fixed terminals. 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, in terms of 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 based on DVB-T standard [1] with 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 a SFN configuration.

• A TDM mode partly derived from DVB-S2 standard [2], in order to optimize transmission through satellite towards 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 (mainly suburban).

The present document 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 at the modulator side is described in details, while processing at receiver side is left open to a particular implementation (as far as it complies with the present document).