D2D

Key Takeaways

• Iridium's $5 billion failure highlighted regulatory resistance to satellite phones
• Launch costs and DSP advances now enable viable LEO mobile constellations
• Starlink plans 840 satellites for D2D, targeting up to 17 Mbps downlink
• Amazon LEO will use Globalstar assets to launch D2D services after acquisition
• AST SpaceMobile proposes wholesale 4G/5G D2D with 223 m² antennae on 95 satellites

Pulse Analysis

The legacy of Iridium serves as a cautionary tale for today’s satellite mobile ambitions. In the late 1990s, the $5 billion constellation faltered because terrestrial carriers lobbied regulators and handset prices were prohibitive. Modern economics, however, have shifted dramatically: reusable rockets have slashed launch costs to under $2,000 per kilogram, and advances in digital signal processing enable higher throughput with smaller, power‑efficient hardware. These factors lower the barrier to entry for new constellations seeking to serve mobile handsets directly from space.

Starlink and Amazon LEO illustrate two parallel strategies. Starlink’s upcoming 840‑satellite D2D tranche promises up to 17 Mbps downlink and 7 Mbps uplink for phones, yet the service remains constrained by handset antenna size and power limits, relegating most mobile use to low‑bandwidth functions like SMS and location. Amazon’s acquisition of Globalstar adds an existing LEO fleet to its portfolio, allowing rapid rollout of D2D services that complement its broadband focus. Both firms treat mobile connectivity as a secondary offering, leveraging their massive broadband constellations to capture niche markets where terrestrial coverage is absent.

AST SpaceMobile takes a wholesale‑first approach, deploying 95 satellites equipped with 223 m² phased‑array antennas to act as space‑based 4G/5G base stations. By operating on the 900 MHz Band 8 LTE and a modest 5 MHz bandwidth, AST aims to deliver conventional voice and data services directly to standard handsets, partnering with local carriers for backhaul. This model sidesteps the retail complexities faced by Starlink and Amazon, but it also inherits the risk that the mobile market may not generate sufficient volume to offset the high capital expense. The ultimate success of D2D will hinge on spectrum access, regulatory alignment, and the ability to price services competitively against entrenched terrestrial networks.