12 GHz spectrum is key to several broadband technologies. First, this is the spectrum that is best suited for transmitting data between the earth and satellite constellations. The only way Starlink is going to be able to grow to serve millions of remote customers in the U.S. is by having enough backhaul to fuel the huge amounts of data that will be passed to serve that many customers. Lack of backhaul bandwidth will significantly limit the total number of customers that can be served and is an obvious major concern of the satellite companies.
It turns out that 12 GHz is also the best spectrum for transmitting large amounts of data with 5G. The carriers have been dabbling with the higher millimeter-wave spectrum, but it’s turning out that there are squirrelly aspects of millimeter-wave spectrum that make it less than ideal in real-world wireless deployments. The 12 GHz spectrum might be the best hope for carriers to be able to deliver gigabit+ wireless drops to homes. Verizon has been deploying fiber-to-the-curb technology using mid-range spectrum and seeing speeds in the range of 300 Mbps. Using the 12 GHz spectrum could provide a reliable path to multi-gigabit wireless drops.
The big question facing the FCC is if 12 GHz can somehow be used to satisfy both needs, pitting the 5G carriers against the satellite carriers. As an aside, before talking more about the issue, I must observe that the satellite companies bring a new tone into FCC proceedings. Their FCC filings do everything except call the other side a bunch of dirty scoundrels. Probably only those who read a lot of FCC documents would notice this, but it’s something new and refreshing.
The current argument before the FCC comes from filings between Starlink and RS Access, which is associated with Michael Dell, who owns a lot of the spectrum in question. But this is part of the larger ongoing battle, and there have been skirmishes that also involved Dish Networks, which is the largest owner of this spectrum.
The FCC will have to somehow untie the Gordian knot on a tough issue. As is to be expected with any use of spectrum, interference is always a major concern. The usefulness of any band of spectrum can be negated by interference, so carriers only want to deploy wireless technologies that have minimal and controllable interference issues. Both sides in the 12 GHz fight have trotted out wireless engineers who support their positions. RS Access says that spectrum can be shared between satellite and terrestrial usage, supporting the idea of not giving more spectrum solely to Starlink. Starlink says the RS Access engineers are lying and wants dedicated spectrum for satellite backhaul. I don’t know how the FCC can sort this out because the only way to really know if spectrum can be shared is to try it.
What I find most unusual about the fight is that the FCC is being dragged into a broadband issue. The last FCC Commission, Ajit Pai, did his best to wash broadband out of the vocabulary at the FCC. But in today’s world, almost everything the FCC does, other than perhaps chasing robocallers, is ultimately about broadband. While this current 12 GHz fight might look like a spectrum battle to an outsider, it’s all about broadband.