San Diego State University — FIGARO-FT (5G Lunar Relay)¶
Lead PI: Satish Sharma, San Diego State University
FO Project: 106617 · TRL 4→5 · Completed Dec 2024
TL;DR¶
SDSU demonstrated a 5G phased-array antenna for LunaNet lunar relay operations in a high-altitude balloon flight test (September 2024). The technology uses commercial off-the-shelf 5G beamformer chips (cost reduction via volume manufacturing) to provide Ka-band BLOS (beyond line-of-sight) communications for lunar surface assets. Outcome: TRL 4→5, SmallSat conference paper published (NTRS 2025), LunaNet compatibility verified. One of the only FO projects explicitly targeting NASA's LunaNet lunar communications architecture.
FO Project¶
| Field | Value |
|---|---|
| Project | 106617 FIGARO-FT |
| Lead Org | San Diego State University |
| Period | Dec 2021 – Dec 2024 |
| TRL | 4 → 5 |
| Views | 3264 |
| Prior work | NASA SmallSat Technology Partnership (STP) initiative |
Technology¶
FIGARO = 5G Array for Lunar Relay Operations
Architecture: Ka-band flat-panel phased array with electronic beam steering, supporting full-duplex communications and simultaneous multi-point contacts. Based on commercial 5G RFIC beamformer technology.
Why commercial 5G chips? The high-volume production of terrestrial 5G hardware has driven unit costs down dramatically. FIGARO exploits this by adapting commercial beamformer ICs for space use — rather than developing custom space-qualified ASICs at 10-100× the cost. Same principle as when SpaceX/Starlink democratized phased arrays.
LunaNet problem being solved: Lunar surface missions often lack line-of-sight (LOS) to Earth, especially in the polar regions targeted by Artemis/CLPS landers. LunaNet requires lunar orbit relay satellites to provide BLOS coverage. FIGARO is a candidate architecture for those relay nodes.
Flight Test¶
Date: September 26, 2024
Location: Hurley, South Dakota
Platform: High-altitude balloon
Altitude: ~98,000 ft (stratosphere, simulating orbital conditions)
What was demonstrated:
- Full-duplex Ka-band communications from altitude
- Both stationary and dynamically moving ground stations
- BLOS relay simulation (Earth ↔ balloon ↔ ground station, no direct LOS)
Result: Architecture validated as viable for LunaNet lunar relay requirements. TRL advanced 4→5.
Publications¶
- NTRS report 20250004153: "FIGARO (5G Phased Array Antenna for Lunar Relay Operations) High-Altitude Balloon Flight Test" — SmallSat conference 2025 paper
- Earlier publication: "5G Arrays for Lunar Relay Operations (FIGARO)" — NTRS 20220006554 (NASA Expo presentation with GRC co-authors)
Co-investigators: Philip Mauskopf, Christopher Groppi, Daniel Bliss (all SDSU/ASU)
Downstream Trajectory¶
Active LunaNet context: NASA SCaN's LunaNet architecture is actively being defined for Artemis. Commercial providers (Nokia, Intuitive Machines, others) are competing for lunar communications contracts. FIGARO positions SDSU as a technology contributor to that market.
Gap to mission: TRL 5 → ready for small satellite demo. No confirmed mission host identified yet. Next step would be a CubeSat or CLPS secondary payload demonstration.
Commercial angle: The COTS 5G beamformer approach reduces cost barriers for small satellite operators providing lunar communications relay services.
Assessment¶
Outcome category: Active Maturation (LunaNet compatibility verified)
Confidence: Suggestive — balloon test confirmed architecture viability; no mission contract
Archetype: Research Tool for Future Architecture — technology validated but awaiting mission host
Dollar amounts: Not tracked in USASpending; university research grant
Surprise level: MEDIUM — the use of commercial 5G COTS chips for lunar communications relay is a non-obvious insight. The connection to LunaNet architecture is clear and well-documented.
Session 16 · 2026-04-06
Session 50 Update: LCRNS Context + SmallSat Presentation¶
LunaNet/LCRNS Progress (Significant Context)¶
NASA's Lunar Communications Relay and Navigation Systems (LCRNS) project has advanced substantially since Session 16:
- Intuitive Machines holds a contract to provide commercial lunar relay services under NASA's Near Space Network (NSN). FIGARO's technology is directly relevant to the relay architecture IM is implementing.
- LCRNS Initial Operating Capability (IOC) targets 2025–2028 — a few relays in lunar orbit matched to provider ground stations.
- NASA published a Lunar Relay Services Requirements Document (SRD) in 2025 (NTRS 20250003321) and a Reference Constellation 3.1 document (NTRS 20250002698).
- A 2025 IEEE Communications Magazine paper ("6G at 1/6g") from University of Maryland frames cislunar communications as a growth area for 6G research.
Implication for FIGARO: The LunaNet market is becoming real, not just a paper architecture. IM's contract means there's a funded buyer for relay technology. FIGARO's COTS 5G approach could be cost-competitive for relay payloads on commercial orbiters.
SmallSat Conference 2025¶
Sharma presented FIGARO results at the 39th Annual Small Satellite Conference (Salt Lake City, August 10–13, 2025). The flight demo achieved: - Successful tracking of each terminal position - Communications links established between ground users via HAB relay - High-resolution video streaming through balloon relay - >100 MB data transfer between ground users
This confirms the SmallSat 2025 paper previously noted (NTRS 20250004153) was an oral presentation, increasing visibility in the smallsat community.
PI Profile Update¶
Satish K. Sharma — IEEE Fellow, Professor and Director of the Antenna and Microwave Lab at SDSU. The IEEE Fellow designation (not noted in Session 16) signals senior standing in the RF/antenna community.
Assessment Update¶
Outcome category unchanged: Active Maturation (LunaNet compatibility verified) Confidence upgraded: Speculative → Suggestive — the gap between "technology validated" and "mission deployed" is narrowing as LCRNS moves from architecture to procurement. IM's relay contract creates a potential customer pathway.
Session 50 · 2026-04-07
Cross-references: fo-portfolio-tracker.md, topics/lunanet-cluster.md