Sponsored by TCI Business Capital
Broadcasters, the wireless and tower industries and the companies who supply them have been planning for a big tower trend — the television spectrum re-pack.
Inside Towers has been covering the FCC’s spectrum auction, the so-called “reverse” sell-off of wireless bidders for spectrum given up by broadcasters. The Commission is now hoping to clear out the 114 MHz spectrum. Reclaiming two fewer UHF channels will give television owners somewhat more room to be repacked.
The FCC has estimated the TV spectrum repack will take 39 months. Generally, wireless carriers agree with that timeline though broadcasters believe it will take much longer. If that estimate holds, it would mean re-pack activities would end sometime in 2019.
But given issues like the limited availability of tower crews that can work on really tall structures, equipment and weather variabilities, the re-pack could take much longer — up to five or six years, by some industry estimates.
During this time, TV broadcasters that typically command the top-mounted position on the towers now need to establish a temporary antenna to accommodate their new channel. That means installing a side-mount antenna that best replicates, as closely as possible, the coverage they had in the top-mounted position.
One difference between now and when TV transitioned to digital: back then television owners didn’t need to completely remove old antennas from the tower, saving them some money; now they do need to remove all the old gear to prevent overloading.
The upcoming re-pack affects more than television stations. What happens with their towers affects co-located FMs as well. Some 1,200 shared TV/radio tower sites house more than 2,350 FM stations; they all face potential disruption of over-the-air service as DTV stations move to lower UHF channels.
One supplier that has been planning to help make the re-pack process easier on customers is Dielectric. The Raymond, Maine-based manufacturer has introduced the DCR-U series of side-mounted, circularly polarized broadband ring antennas that can be quickly deployed to provide reliable, uninterrupted FM radio transmission.
“Depending upon what their TV broadcast neighbors decide to do, the FM radio tenant sharing the tower may need to move its side-mounted FM radio antenna to a lower elevation on the tower, or in the case of significant tower work, relocate its entire RF transmission operation to a different tower altogether,” says Dielectric VP/GM Keith Pelletier. “They may also need to install other RF components, such as mask filters or a combiner, to prevent undue signal interference in situations where multiple stations now operate on a temporary site.” The company says it can save FM and HD Radio broadcasters up to 60 percent in costs using its ring-style antennas and new filters.
All suppliers connected with the re-pack are recommending radio owners discuss tower strategy with their TV brethren, as well as the tower companies themselves to get a good understanding of their RF plans. “They should also consider conducting a coverage study to understand how their coverage patterns may shift relative to changes in tower position,” says Pelletier. Our Dielectric Antenna Systems Planning (DASP) software can help broadcasters and their RF consultants build a model to simulate how a shift in azimuth pattern could impact their overall coverage, saving them valuable time in the ramp-up to the TV spectrum re-pack.”
Dielectric is displaying its new products at the upcoming NAB/RAB Radio Show in Nashville, Tennessee, September 21 to 23. The company also plans to have members of its engineering team on hand in booth 11 to discuss viable strategies with radio broadcasters to help them handle the unfolding challenges posed by the re-pack.