LA TV stations KLCS and KJLA have concluded their channel sharing trials, and the results are good news for the Federal Communications Commission, which hopes to auction off a large chunk of the broadcast airwaves to mobile carriers next year. Their report, released to the public on Friday, found there are few technical barriers to two broadcasters sharing the same 6 MHz channel.
In 2015, the FCC is trying to pull off an enormously complex incentive auction. The key to that plan is convincing broadcasters that they can consolidate onto fewer TV channels, selling off their vacated spectrum in a reverse auction. The FCC would then reconfigure the 600 MHz bands, repackaging those TV airwaves into licenses carriers could use. Mobile operators would then bid on those licenses in a regular auction.
Working with mobile carrier industry group CTIA, KLCS and KJLA found that it was not only feasible for two TV stations to run two separate 720p HD video feeds over the same 6 MHz channel, but they also could include two standard definition streams in the same bandwidth without having any major impact on video quality. That’s a key finding because many broadcasters already transmit the HD and SD versions of their programming on the same channel. This shows it’s possible to continue the same practice through channel sharing.
The stations went further, testing 3 HD streams and many more combinations of SD and HD programming. While they were successful in many cases, the reports’ authors warned that there were quality trade-offs. The more complex the digital content, the more a video feed would suffer from a constrained bandwidth – sporting events need more capacity than talking head programs.
The trial also found that the TVs and digital tuners it tested had no problems receiving and parsing the different feeds, allocating each station’s programming into the correct virtual channel on the TV dial.
Though trials like these could convince broadcasters of the technical feasibility of channel sharing, there are still a lot of issues on the table. National Association of Broadcasters EVP for strategic planning Rick Kaplan this week said broadcasters are still mistrustful of carriers and the FCC, fearing they’ll change the rules in the middle of the auction of after it closes, FierceWireless reported.
Right now the FCC is engaged in a marathon rule-making process, determining everything from how the spectrum would be split up by different geographies and whether carriers like T-Mobile(s tmus), Sprint(s s) and rural carriers would be given competitive advantages in the auction. The FCC is also weighing how much of the freed-up spectrum to allocate for unlicensed use, which could fuel white space broadband. Right now, Telecompetitor reported, it doesn’t look like the FCC plans to open up any major chunks of frequencies for unlicensed use.