May 11, 2023 | By Donny Jackson | IWCE Urgent Communications |
AT&T told the FCC that it has agreed to have satellite-direct-to-phone company AST SpaceMobile provide supplemental-coverage-from-space (SCS) services to its subscribers and asked the FCC to approve waivers that allow AST to operate on leased spectrum from AT&T in the 700 MHz and 850 MHz bands.
In a filing to the FCC made public today, AT&T stated that the spectrum-lease agreement will become effective in 21 days—the end of this month—but the carrier giant stipulated that AST “would not commence using the leased spectrum without obtaining all necessary Commission approvals.”
AT&T has been testing AST’s satellite-direct-to-phone technology—dubbed SCS by the FCC and known as “direct to device” (D2D) by many in the telecom industry—for several months, but today’s filing represents the first public statement of a major U.S. carrier committing to adopt such a service. Last month, AST announced that it completed the first satellite-direct-to-phone voice call from a user in Texas over AT&T spectrum to a Rakuten subscriber in Japan.
Ultimately, AST plans to deliver satellite-direct-to-phone connectivity via its constellation of 168 massive low-earth-orbit (LEO) satellites will act as “cell towers in space,” so they work with unmodified smart devices in the same way as a roaming partner’s terrestrial cell towers do. Providing wireless coverage to subscribers located outside the working footprint of AT&T’s terrestrial network is a priority for the carrier in this deal, according to the carrier’s filing with the FCC.
“AT&T’s terrestrial network already covers over 290 million Americans and more than 2.91 million square miles,” AT&T’s filing states. “ In collaboration with AST, it expects to provide mobile broadband to unserved and underserved areas covered by the leased spectrum. Moreover, with AST’s advanced satellite technology, this SCS will be provided without harmful interference to adjacent or co-channel networks.
“In other words, the AT&T/AST collaboration will use spectrum efficiently. Because AST’s technology can focus satellite coverage in discrete portions of licensed areas, it does not need a nationwide swath of terrestrial mobile spectrum that a mobile network operator licensee has left fallow. Rather than displacing terrestrial network facilities nationwide, AST’s coverage will be complementary to AT&T’s extensive terrestrial network coverage.”
In March, FCC commissioners voted to launch a proceeding that would establish a regulatory framework for SCS operations—communications that differ from both traditional satellite and traditional terrestrial wireless offerings—but noted that agency still would consider “requests for rule waiver” prior to the SCS framework being completed. AT&T’s filing seeks such waivers.
AT&T’s waiver requests would let AST provide satellite-direct-to-phone services on 850 MHz and lower 700 MHz spectrum licensed to “seven indirect subsidiaries of AT&T,” according to the filing.
AT&T has been conducting tests with AST SpaceMobile that include utilization of the 700 MHz Band 14 airwaves licensed to the FirstNet Authority, which contracted AT&T to build and maintain a nationwide public-safety broadband network (NPSBN) as part of a 25-year deal signed in March 2017. That Band 14 spectrum is not part of the AT&T-AST leasing agreement outlined in today’s waiver request. Indeed, such a waiver request would have to be initiated by the Band 14 licensee—the FirstNet Authority—according to industry sources.
FirstNet subscribers have been able to access AT&T’s commercial spectrum—such as the bands included in the deal with AST—with priority and preemption rights on the carrier’s terrestrial network for years. A similar FirstNet arrangement eventually is intended when connecting to AST’s satellite constellation, but many technical and operational details must be resolved first.
Indeed, AST is still very early in the deployment of its LEO satellites. The BlueWalker 3 test satellite (pictured above) that is being used during the testing with AT&T and other carriers is large, but the first five BlueBird satellites—with greater RF capabilities than the BlueWalker 3—are scheduled to be launched during the first quarter of 2024 and will be the first of AST’s commercial satellites.
Scott Wisniewski, AST SpaceMobile chief strategy officer, described the significance of the AT&T filing in a May 12 statement provided to IWCE’s Urgent Communications.
“Today marks a significant milestone in our company history, with AT&T filing with the FCC a lease with AST SpaceMobile for substantially all of its low-band spectrum in the United States,” according to Wisniewski’s statement. “This agreement brings AST SpaceMobile one step closer to offering cellular broadband from space directly to everyday smartphones. Together with AT&T, we are making strides to eliminate mobile connectivity gaps and bring broadband to those in remote and underserved areas around the world. We’ve already seen initial technical success with our network in April, completing voice calls from space to many different off-the-shelf smartphones, using the BlueWalker 3 test satellite.”
Previously, Wisniewski offered some details about the company’s LEO satellites in the aftermath of its successful Texas-to-Japan voice call last month.
“The BlueWalker 3, the test satellite, which is in orbit now, provides five to 10 minutes of coverage as it passes directly over a given area,” Wisniewski stated in a e-mail to IWCE’s Urgent Communications. “The five Block 1 BlueBird satellites are based on a substantially similar design but with a significant upgrade in RF capabilities. The Block 2 BlueBirds are larger in size and will provide a coverage area of over 2x the size, and thus coverage for 2x the time.
“When the full network constellation is deployed, it will offer continuous coverage globally.”
Even with the BlueWalker 3 tests, the audio quality “was akin to any call you might make over a rural cell phone tower,” according to Wisniewski. “The latency is minimally higher, but not high enough that the human ear can detect the difference.”
Wisniewski also stated that AST SpaceMobile’s engineers found “only a negligible difference in battery life” when connecting to a LEO satellite when compared to connecting to a terrestrial tower.
FCC representatives and other federal officials have expressed excitement about the quickly evolving satellite-direct-to-phone industry, which promises to provide connectivity to outdoor locations where that are uneconomical for commercial carriers to cover with terrestrial infrastructure.
In addition, the public-safety implications of satellite-direct-to-phone technology promise to be significant, allowing people to communicate with 911 from even very remote locations during an emergency. An emergency text service offered to Apple iPhone 14 users via the Globalstar satellite network already has been used to save people in dire circumstances, according to multiple media reports.
Meanwhile, SCS service potentially could address two key issues associated with IP-based first-responder communications. Satellite-direct-to-phone services would expand the coverage footprint and offer a much-desired level of resiliency to LTE and/or 5G networks. It also could be used to meet the need for a seamless alternative when a user is outside of the terrestrial-network coverage that provides much greater range outdoors than direct-mode connectivity provided by LMR devices.
Of course, AST SpaceMobile is not the only company attempting to provide satellite-direct-to-cell-phone services.
Lynk Global, which recently had its agreement with Canadian carrier Rogers Communications announced publicly, has a similar business model but a very different system architecture. While AST SpaceMobile plans to provide cellular broadband service globally with 168 LEO satellites, Lynk plans to deploy thousands of smaller LEO satellites to support eventual broadband connectivity, although its initial offerings will be text-only services.
Lynk also is the first satellite-direct-to-cell-phone company to receive an FCC license for commercial operations, although the license only applies to 10 satellites.
Both Lynk and AST SpaceMobile eventually plan to offer broadband services to users, while many other satellite-direct-to-phone providers are focused on lower-bandwidth applications.
Other significant developments in the satellite-direct-to-cell-phone arena include T-Mobile and SpaceX announcing plans last August to provide connectivity leveraging 1.9 GHz spectrum. Last September, Apple announced that it has teamed with Globalstar to provide an emergency text service—known as Emergency SOS—via satellite that launch in November on 2.4 GHz spectrum for iPhone 14 users.
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