Amateur radio CubeSat · design phase
SMART-QSO
A 1U CubeSat that will carry a single-channel FM transponder for amateur radio contacts worldwide, switched on only when the power budget allows, and a 1200 bps AX.25 telemetry beacon. Its experiment is onboard AI that schedules the transponder within the power budget and chooses the beacon's plain-language text. If the AI is off or fails, it is a conventional transponder with template beacons. SQSO-BL-001 §2
- 1U body, 100 × 100 × 113.5 mm
- Solar wing (one of two)
- 2 m element (≈ 0.5 m, shortened here)
- 70 cm element (≈ 0.17 m)
- ISIS AntS on the −Z face
Drawn from the mechanical design's dimensions; the 2 m elements are shortened to fit. SQSO-MECH-CAD-001 §3.2, §5.2
Where the project stands
- Design phase. The project is in Phase B (pre-PDR). No hardware has been bought or built, and every figure is a prediction, none a measurement. SQSO-BL-001 §1 SQSO-REV-CDR-002 §7.2
- Software runs in simulation. The flight software (Rust, on the Embassy executor) runs as a host simulation and builds as an STM32L4R5ZI image that CI checks; it has not run on hardware. SQSO-REV-CDR-002 §7.2
- Reviewed, but not by an independent board. A design review against the NASA CDR criteria finished on 2026-10-27. It was carried out by AI reviewers, not an independent review board, and it rates the project at the level of a strong PDR, not past a CDR. The independent PDR is planned for 2027-01-12. SQSO-REV-CDR-002 §1.2, §7.2
- No licence, no frequencies, no launch contract yet. No regulatory filing has been made; the IARU coordination request is not submitted, so there are no coordinated frequencies. The launch contract is due by 2027-06-30. SQSO-REG-004 SQSO-SCH-001 §1
Key numbers
From the baseline, revision E of 2026-10-27, which governs every design value, and the CDR 2026 review report.
- 1U CubeSat
- 100 × 100 × 113.5 mm SQSO-BL-001 §4
- 1.52 kg current best estimate
- 1.75 kg with growth; limit 2.00 kg (+14.0 %) SQSO-BL-001 §4
- 475 km sun-synchronous orbit
- 97.31° inclination; cap 485 km; LTAN 22:30 SQSO-BL-001 §3
- 2 years design life
- minimum mission 12 months SQSO-BL-001 §2
- 0.5 W downlink, nominal
- 1 W maximum; 2 m band down, 70 cm up SQSO-BL-001 §7
- 3.84 W power, sun-pointed, end of life
- 2.48 W tumbling; ≈ 50 Wh battery SQSO-BL-001 §5
- 2028-11-01 planning launch date
- the last Transporter rideshare of 2028; not contracted SQSO-REV-CDR-002 §3.1
- 412 review findings (RIDs)
- none open for implementation SQSO-REV-CDR-002 §6
What the AI does, and what it does not
Flight baseline: a selector on the flight computer
A small calibrated model on the STM32L4R5 flight computer picks among pre-approved beacon templates and proposes the power mode and the transponder schedule. Hard limits stay outside the model: no AI output can override the power gates, the transmit inhibits or TX-OFF. It is designed, not yet implemented; today the flight software sends its fixed templates in turn. SQSO-BL-001 §6 CONOPS.md §5
Gated experiment: generated text on the Jetson
A power-gated NVIDIA Jetson Orin Nano module can generate beacon lines with a small open language model (SmolLM2-360M or Qwen3-0.6B) in bursts of at most 10 minutes. It flies as an experiment only if the energy per accepted beacon line, measured on the engineering model, is at most 0.1 Wh. Generated text carries no numbers and passes the same content filter as the templates; the flight computer writes every value from measurements. SQSO-BL-001 §6
How it reaches orbit
The planned path, as the design review traced it. None of it is contracted yet: requests for quotes go out by 2026-12-31. SQSO-SCH-001 §1
SpaceX Falcon 9
A Transporter-class rideshare to sun-synchronous orbit from Vandenberg SLC-4E. SQSO-REV-CDR-002 §3.1
Exolaunch
The integrator: SpaceX's customer. SMART-QSO would contract with the integrator, not with SpaceX. SQSO-REV-CDR-002 §3.1
EXOpod Nova
The dispenser. The CubeSat is loaded about 47 days before launch, unpowered, and is not touched again. SQSO-REV-CDR-002 §3.1
475 km SSO
Drop-off at a 475 km target, never above 485 km, a limit the contract must state. SQSO-REV-CDR-002 §3.1
Re-entry
No propulsion: the orbit decays naturally with the wings deployed, within 5 years of the end of the mission. SQSO-BL-001 §3
The launch chain in full, and the timeline from separation to re-entry →