Coalition seeks to share federal frequencies for mobile broadband backhaul

The Fixed Wireless Communications Coalition (FWCC), on the same day that the FCC released its new National Broadband Plan, offers to solve one of the problems identified in the Plan.

We all know about the growth in mobile broadband, driven largely by people watching Internet TV and videos on their phones and laptops. The FCC’s efforts to find more spectrum for these applications – efforts that might involve even auctioning off TV channels – are getting a lot of attention. Less conspicuous is the parallel problem of “backhaul”: moving data back and forth between the network and the cell towers that communicate with all those mobile devices. Today most cell towers connect with copper wire that Alexander Graham Bell would recognize. It works fine for voice calls, but lacks sufficient capacity for broadband. At some locations optic fibers are an option. Other cell towers, though, especially at remote locations or in rugged terrain, are best reached by microwave radio links. And that requires . . . Raise your hands, class . . . anyone? Yes! More spectrum!

Fortunately backhaul signals ride best on higher frequencies than mobile broadband, so the two need not compete. The 4-10 GHz range is the backhaul sweet spot. Below that the antennas are too big; above, radio waves are impeded by rain.

The “fixed service” – an FCC category that includes backhaul – has allocations at 4 and 6 GHz. But their use is severely limited by satellite operations in the same bands, except for a satellite-free slice at 6 GHz. The only other “fixed” allocation below 10 GHz is a huge Government-only swath at 7125-8500 MHz.

With nowhere else to go, the FWCC has now asked the FCC to let non-Government users, including backhaul providers, share the 7125-8500 MHz band with the Government. Also involved in the decision will be the National Telecommunications and Information Administration (NTIA), a part of the Department of Commerce that manages spectrum for all U.S. Government agencies.

There is precedent for the idea. The fixed service band at 21.2-23.6 GHz has been shared between Government and private users for many years, with great success. The one problem, from the private users’ standpoint, is the delay in licensing on most frequencies due to the need for coordination with NTIA. To avert that delay in the 7125-8500 MHz band, the FWCC proposes a database of both Government and private usage so that private frequency coordinators can determine quickly whether a given link can be safely constructed.

It remains to be seen whether NTIA will go along. We all share so much with the Government, it seems only fair to ask the Government to share a little back. Except, of course, for the frequencies that control the Black Helicopters. They can keep those.