The NTN Spectrum Wars: Is MSS Becoming the Only Viable Path Forward?

Are terrestrial spectrum-sharing frameworks like the FCC’s SCS and ISED’s SMCS failing to provide viable bandwidth, pushing Non-Terrestrial Network (NTN) operators to aggressively pursue Mobile Satellite Service (MSS) spectrum for greater independence and scalability? Recent developments suggest that the spectrum battle is shifting from terrestrial networks to orbital assets. There are growing indications that terrestrial mobile spectrum designated for satellite applications under these frameworks may not produce the outcomes satellite network operators need. Recent moves by companies like SpaceX and AST SpaceMobile underscore this trend. The drive to secure MSS spectrum reflects a broader strategy among NTN operators to escape regulatory constraints and safeguard their financial future through bold and increasingly aggressive measures.

Two Operational Models for NTN Services

There are two models for operating NTN services. The first relies on MSS spectrum, which enables independence from mobile network operators. Globalstar best represents this model, offering services in partnership with Apple that benefit from its priority rights to MSS spectrum in the following bands:

• User links: MSS band
  • Uplink (mobile to satellite): L-band 1610–1618.725 MHz (8.725 MHz)
  • Downlink (satellite to mobile): S-band 2483.5–2500 MHz (16.5 MHz). Regulators have also licensed this band for terrestrial use, including 11.5 MHz in the U.S.
• Feeder links: C-band
  • Uplink (gateway to satellite): 5091–5250 MHz (159 MHz)
  • Downlink (satellite to gateway): 6875–7055 MHz (180 MHz)

In contrast, operators such as SpaceX, AST SpaceMobile, and Lynk rely on frameworks such as the FCC’s SCS (Supplementary Coverage from Space) to operate direct-to-device services using terrestrial mobile spectrum. For instance:

• SpaceX: Provides services in partnership with T-Mobile over the PCS Block G (2×5 MHz) (Band 25):
  • Uplink: 1910–1915 MHz
  • Downlink: 1990–1995 MHz
• AST SpaceMobile: Conducted trials with AT&T and Verizon over the Cellular 850 MHz band (Band 5), which for the AT&T trial in Midland, TX used:
  • Uplink: 846.5–849.0 MHz
  • Downlink: 891.5–894.0 MHz

Critical access to spectrum

In both examples, operators have allocated only a limited amount of spectrum to NTN that is sufficient for text messaging services, but commercially impractical for voice and data applications. In effect, viable NTN businesses will require significantly more spectrum for voice and data than what is currently allocated by mobile network operators (MNOs). Frameworks such as SCS are practical when terrestrial operators possess surplus spectrum assets that can be dedicated to NTN applications without impacting mobile services. For instance, T-Mobile does not heavily utilize PCS Block G. By contrast, AT&T and Verizon make extensive use of the 850 MHz band, particularly in rural areas, and have only allocated a narrow slice of spectrum that far below what AST would need to meet its advertised 30 Mbps data throughput target.

The fight over MSS spectrum

NTN service providers have come to fully recognize the need to access spectrum that is independent of terrestrial allocations. SpaceX took steps to pursue Echostar’s MSS spectrum (2000–2020 MHz and 2180–2200 MHz) when, in March of this year, it filed a letter with the FCC challenging Echostar’s use of the AWS-4/MSS band (see here). The FCC subsequently opened an inquiry into how Echostar utilizes this band and plans to issue a ruling in the coming weeks or months.

On the other hand, AST initiated two major spectrum acquisition efforts:

• It acquired rights to 40 MHz of Ligado’s L-band spectrum for over 80 years in the United States and Canada, along with an additional 5 MHz of L-band spectrum in the 1670–1675 MHz range in the United States. AST will pay $550 million for the spectrum, with $535 million going to Inmarsat/Viasat to settle Ligado’s outstanding debts. Ligado’s L-band rights span 1626.5–1660.5 MHz for uplink and 1525–1559 MHz for downlink.
• On August 6, AST announced that it had acquired priority rights to 2×30 MHz of global S-band MSS spectrum in the 1980–2010 MHz and 2170–2200 MHz bands for $64.5 million. This transaction is currently awaiting national regulatory approvals.

MSS as a differentiation

Access to MSS spectrum is becoming increasingly important for NTN constellation operators. It provides a path to independence from MNOs and offers the bandwidth needed to deliver differentiated services. It also helps reduce the impact of limitations imposed by frameworks such as SCS, particularly those related to out-of-band emission restrictions and interference mitigation (see here).

AST has stated that its MSS spectrum strategy, combined with operator spectrum, will enable it to deliver speeds of up to 120 Mbps (30 Mbps per 10 MHz). This is a highly ambitious goal for NTN services and would require substantial spectrum resources.

Concluding thought

The aggressive pursuit of MSS spectrum through acquisition, regulatory challenges, or long-term leasing marks a decisive shift toward strategic independence for NTN operators. In the race for dominance, spectrum is the ultimate currency, and the rules of the game are still being written. The value of MSS spectrum will continue to rise as it becomes a focal point of competition among NTN operators. What was once a niche asset is now a battleground for strategic positioning, long-term viability, and control over the future of direct-to-device satellite connectivity.

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Update – August 14, 2025

LightReading published an update on AST SpaceMobile acquisition of S-band spectrum (link). Some of the highlights that add to the context:

• AST SpaceMobile is acquiring the S-band spectrum from CCUR Holdings, Inc. and EllioSat Ltd. according to a SEC filing (link).
• The spectrum is not valuable because it has lower priority than rights held by Echostar and Omnispace.