The same day that SpaceX scored a big win about proper use of spectrum, it became embroiled in a new fight over appropriate spectrum use. The new fight is with AT&T over SpaceX’s plans to enable calls from T-Mobile cellphones via SpaceX satellites.
That type of service is called supplemental coverage from space (SCS) and is a market AT&T also is pursuing via a deal with satellite operator AST. In a filing with the FCC, AT&T expresses concern that the planned T-Mobile/SpaceX service, which will use spectrum in the PCS G-block, could interfere with AT&T cellphone operations in the adjacent PCS C-block.
AT&T’s filing was made the same day that the FCC declined to allow two-way mobile operations between 12.2 GHz and 12.7 GHz out of concerns that doing so would interfere with SpaceX Starlink satellite broadband service that also operates in the band.
Supplemental Coverage from Space (SCS)
As previously reported by Ars Technica, AT&T’s filing last week was made in response to SpaceX’s request to modify its license to add direct-to-cellular communications on Starlink satellites. The FCC sought comment on that request, and AT&T is one of several entities that have filed comments expressing concerns about those plans.
The FCC is still in the process of determining how to regulate SCS service.
AT&T’s recommendation, as noted in its filing on Thursday, is that “the best path forward for SCS is a waiver-based approach that vests the [FCC] with sole authority to permit SCS operations in terrestrial mobile frequencies. Such an approach allows the FCC to ensure that applicants meet the high standard required for waiver and that SCS operations will not present any risk to terrestrial wireless operations of all licensees, including collaborating carriers.”
In keeping with this recommendation, AT&T earlier this month made a filing with the FCC indicating its intent to lease spectrum to AST and requesting several waivers. For example, the carrier asked for a waiver of cellsite height restrictions, which would not be pertinent to a space-based cellsite.
In the newer filing expressing concerns about SpaceX and T-Mobile plans, AT&T said that SpaceX and T-Mobile had not requested these waivers, and therefore the FCC should reject the SpaceX/T-Mobile waiver requests that the partners did make.
AT&T and AST “intend to provide the demonstrations necessary to show that they will not cause interference to any authorized terrestrial systems,” AT&T added.
The carrier also noted that AST already has made progress on this front, recently completing a call from an unmodified cellphone in the U.S. to Japan via an AST satellite.
T-Mobile and SpaceX technical showings are “woefully insufficient regarding the risk of harmful interference posed by their planned SCS deployments,” AT&T said.
AT&T urged the commission to require T-Mobile and SpaceX to demonstrate, not only that their planned service would not interfere with other carriers’ terrestrial services but that it also would not interfere with T-Mobile’s own terrestrial offering.
T-Mobile did not immediately reply to an inquiry from Telecompetitor requesting comment on AT&T’s filing.