Direct-to-device (D2D) satellite communications present significant challenges, both financial and technological, that are closely interconnected. Addressing one set of challenges often increases the risk in the other. Different D2D constellations have adopted various strategies to balance commercial and technological risks. In our latest Insight Note, which you can download below, we highlight some of the key technological risks and examine how two leading satellite constellations are currently working to mitigate them.
Download our latest Insight Note: Understanding the Risks in Direct-to-Device Satellite Communications: Insights from SpaceX and Globalstar
Key Takeaways
- Addressing the range and interference challenges requires engineering trade-offs the significantly impact performance and profitability.
- D2D communications face several challenges, with range (distance between the satellite and mobile device) and interference management being critical.
- The two leading direct-to-device constellations today are SpaceX, set to begin offering services in fall 2024, and Globalstar, which already provides D2D services through a partnership with Apple.
- SpaceX and Globalstar differ in their business models and technology strategies, influenced by spectrum regulations and legacy licenses, which significantly impact performance and profitability.
- Globalstar operates at an altitude of 1,414 km, much higher than SpaceX’s 340 km, leading to greater propagation losses that require higher system gain to overcome for the same grade of service.
- SpaceX uses terrestrial mobile spectrum under new regulatory frameworks like SCS, necessitating licenses across large areas (the entire continental U.S. in SCS) to avoid co-channel interference. In contrast, Globalstar leverages its existing MSS spectrum, already licensed globally, enabling operation independent of new frameworks like SCS.
- Frameworks like SCS impose additional requirements on D2D satellite constellations to minimize interference with terrestrial mobile networks. These requirements include out-of-band emission limits and geographic licensing coverage.
- Addressing the range and interference challenges requires engineering trade-offs that have significant impacts on both performance and profitability of the D2D satellite constellation.