Single Frequency Network: the same signal is radiated from multiple locations simultaneously and on the same frequency. This technique is particularly suited to digital transmissions. The standard for DVB-T digital terrestrial television allows you to exploit this opportunity.
Projects with this TAG (3)
New DVB technology to serve satellite customers and to feed terrestrial transmitters
Today, the satellite distribution of DVB-T2 multiplexes to terrestrial transmitters located throughout the territory requires dedicated transponders for the transport of the relevant T2-MI (Modulator Interface) streams, which are not directly accessible also for direct-to-home reception by standard satellite receivers. This causes duplication of the needed satellite bandwidth, with the associated costs. To overcome this problem, DVB (Digital Video Broadcasting) has activated a new ad-hoc group, named TM-T-JSI, with the purpose of defining an optimized way to transport DVB-T/T2 multiplexes from a national head-end to the terrestrial transmitters, while allowing at the same time direct reception via DVB-S/S2 commercial satellite receivers.
SFN Scope: an innovative analysis system for DVB-T SFN signals
Created and patented by Rai-CRIT, SFN-Scope can analyze SFN DVB-T signal received in the service area, and identify the individual components of the signals emitted from transmitters in service to the area, with their levels and delays. SFN-Scope thus makes now possible to simplify the signal quality control operated by RaiWay teams, and get actual feedback for level/delay measurment that until now were only available in a “aggregate” form by ordinary instruments.
Laboratory evaluation of the Demetra system for the distribution of time / frequency references via geostationary satellite
In October 2016, at the Laboratory of Rai CRIT, it was carried out a series of tests on the demonstrator for time synchronization and frequency alternative to GNSS (Global Navigation Satellite System), developed by Antares S.c.ar.l under the European Demeter project, in collaboration with INRIM.
The tests have allowed us to evaluate the behavior of the developed system, especially in reference to the specific needs for synchronization of a network of DTT transmitters in single frequency (SFN).