We may no longer be sure what is being referred to when we say “TV,” but whatever it is, we watch a lot of it. Depending upon the poll and the region, data indicate that adults spend, on average, anywhere from 3 to 9 hours a day watching “It” on screens of all types.
Along with TV viewing, content fidelity is also increasing. Service providers are now challenged with distributing UHD video (up to 8K) and next-generation immersive audio, among other bandwidth-thirsty enhancements over all types of networks. More devices, content and viewing, along with bigger pictures and sound, bring us to one of our favorite topics—bandwidth and efficient radio spectrum use.
Radio spectrum is finite and, given the current trends, we may need almost all of it soon just to deliver all this “TV.” Incremental technical improvements are keeping our heads above the “full capacity” water, but it may be time for more radical measures. One of those measures might be sharing. Sharing may not seem all that radical, but in the context of how spectrum is used today, it is. For the most part, individual entities are granted the use of a single spectrum slice. And, for the most part, they don’t share their slice with their neighbors.
We wrote recently about the beginnings of U.S. terrestrial broadcasters building new networks where they share infrastructure and transmission equipment to deploy next-generation TV services. European broadcasters have been using this multiplex operation system for many years and now they are considering taking sharing to a new level with an emerging technology called Wideband Re-Use 1, or WiB.
WiB is currently being studied by the standards-setting group the DVB Project as a potential next-generation digital terrestrial TV (DTT) standard—both from a technical and a commercial perspective. No adoption decisions have been made but the idea of adopting a standard that could fundamentally change how spectrum is used by TV broadcasters is intriguing. Like many other technologies, there are a variety of ways it can be implemented and “the sharing” concept is only one possible implementation. The technology comes with another extremely attractive attribute—ultimately, the system would require significantly less power and could produce big operational cost-savings.
If the sharing capability were implemented, it might enable the building of a “supermux,” which could create, in any given coverage area, a network that radiates from a single transmitter (a wide signal that occupies all available channels in the UHF band). In theory, that “supermux” of over 200 mb/s could contain all the program content over the entire area. That would mean one transmitter and one multiplex shared by all area spectrum licensees in the UHF band.
Apparently WiB’s secret sauce is how it could minimize the interference that occurs when the same RF channels are used in adjacent service areas. In theory, WiB networks would get rid of the need for “guard bands” that aren’t used for transmitting signals, but for creating space between channels to avoid interference.
If broadcasters wouldn’t need those buffer channels for combatting interference, those channels could be used for transmitting signals. But first broadcasters would have to agree to some sharing. That should be OK. After all, our mothers told us it’s something we should do. Perhaps, it would set a good example for others in the radio spectrum-use sandbox.