Television plays an important role in society and is still a key tool to access information for French audiences: in 2015 they devoted an average of 3 hours and 44 minutes per day to watching it and 92% of the population had at least one weekly contact with TV (see Enquête Médiamétrie 2015).
Originally, television was exclusively broadcast via terrestrial technology, but its means of access have diversified over the past thirty years. Some are now based on wired infrastructure (cable, ADSL or fibre) while others are still using spectrum in various wavelengths: DTT, satellite, mobile data networks or Wi-Fi. This diversity of access is reflected in the no less diverse variety of terminals on which to watch programmes: TV sets, tablets, computers and smartphones. Simultaneously, consumption of audiovisual content, which used to be entirely linear, now includes video-on-demand and interactive audiovisual services. Finally, digitisation of the signal has paved the way for general access to high-definition (HD) and the birth of ultra-high-definition (UHD) or 4K, capable of broadcasting cinema-quality pictures in a format suitable for the ever increasing dimensions of home TV screens.
These developments have contributed to modifying the space occupied by broadcast television, either via satellites (22.1% of households) or DTT (55.9% of households in the second quarter of 2016).
Two frequency bands in succession were released by the terrestrial platform, one in 2010 and 2011 (the 800 MHz band, transferred to mobile communications), and the other is expected for clearance between April 2016 and mid 2019 (the 700 MHz band, given over in part to mobile communications and the rest to security networks). This repurposing became possible because of the move to digital broadcasting which greatly improved the platform’s spectrum efficiency so that, with fewer resources, the number of terrestrial channels could be increased thanks to DTT, and HD broadcasting could be rolled out widely. In keeping with the proposals contained in P. Lamy’s report to the European Commission, regulatory authorities were keen to guarantee that the UHF band currently used by DTT (470-694 MHz) would continue to be allocated to the audiovisual sector until 2030. This decision was ratified by law.
In coming years, television transmission will no doubt be witness to the appearance of new standards enhancing spectrum efficiency, in the wake of the second-generation Digital Video Broadcasting-Terrestrial Transmission standard (DVB-T2) or the High Efficiency Video Coding Compression standard (HEVC). These standards are due for deployment by 2020 in some European countries, Germany among them. In France, CSA has begun working on the future of standards and usage on the DTT platform.
Since programmes for terrestrial broadcasting tend to vary in richness of content from one country to another, the 470-694 MHz band, which is entirely occupied by DTT in France, features some available capacity in other countries. Some countries, like Finland, are thinking of using this resource to extend the mobile network although they are committed to making sure that in doing so they do not interfere with audiovisual broadcasting in neighbouring countries. In the United States, because of the preponderance of cable and satellite broadcasting, the space reserved for terrestrial television is already smaller than in Europe. As a result, the 600 MHz band in the United States is currently being allocated to other services.
Turning to satellites, the vast areas covered by geostationary satellites qualify them as excellent broadcasting platforms. Thousands of television channels and radio stations use satellites to broadcast programme content in Europe and their numbers are constantly growing. In France, all of the DTT channels are broadcast in HD via two satellite platforms. Satellite technology pioneered improvements to TV broadcasting formats: digital broadcasting was introduced in the 1990s, then high definition arrived in 2005 (and it is expected that by 2020, HD channels will be generating 20% of the satellite broadcasting market) and finally, today, UHD has just arrived on the scene. As with the terrestrial platform, this new format will be facilitated by the HEVC video compression standard. One of the advantages of the satellite platform for UHD broadcasting is its immediate availability: satellites already in orbit are technically capable of broadcasting a large number of extra UHD channels without delay.
Although, strictly speaking, it cannot be classified as a broadcasting application, satellite broadcasting also plays a crucial role in the distribution of DTT channels by feeding content to terrestrial transmitters. Most of these transmitters are not fed by cable or fibre, but by radio relay either from a nearby terrestrial relay or a satellite. In France, therefore, satellite broadcasting contributes indirectly to the transmission of DTT throughout the country.
As for the frequency bands in use for satellite broadcasting, almost all the satellites currently transmitting to Europe do so via the 13-14 GHz/10-11-12 GHz frequency range. This being the core range for satellite broadcasting in Europe, it seems clearly earmarked for hosting today’s channels well into the future and providing room for expansion to house the new channels constantly being created.