RadFXSat-2 (Fox-1E) Spacecraft

Demonstrate a short interval, cost-effective, on-orbit platform for qualification of components for space.

Demonstrate a short interval, cost-effective, on-orbit platform for enhanced qualification of components for space flight. The data collected will be used to validate and improve computer models used to predict radiation tolerance of integrated circuits. Also serve as a communications relay for amateurs worldwide via the onboard transponder system. The communications and experiment missions will run concurrently.

FoxTelem has received SEU data from RadFxSat-2 since approximately July 23, 2021 (the six-month gap between launch and first data packet delivery will be discussed in the following section). The REM experiment was dead-on-arrival, so only the LEP and LEPF experiments have recorded data. Results up to January 8, 2023, are presented.

The RadFxSat-2 satellite has provided the first on-orbit SEU data for a FinFET-based SRAM, producing rates that leave the authors optimistic for FinFET usage in LEO. Although technology below the 65 nm scale is more susceptible to low-energy protons, SEU rates within a proton-heavy environment such as LEO may still be within acceptable limits for many missions, especially if error-correction mechanisms are enabled.

As mentioned previously, there was a 6-month delay from the RadFxSat-2’s launch and reception of telemetry. This was due to communication issues with the satellite – extensive recovery attempts during this time produced no results, and the satellite’s telemetry downlink was feared to be dead-on-arrival.

RadFxSat-2 signals were, in fact, transmitting, but the signals were very weak. Extremely sensitive amateur radio satellite ground stations (namely, the Dwingloo 25m radio telescope, owned by ASTRON) listening on RadFxSat-2’s TLM downlink frequency picked up on telemetry frames from the satellite, allowing for communication debugging. Details of the debugging steps were published in The AMSAT Journal. It is hypothesized that a dual power amplifier chip onboard shorted which, coupled with an antenna that did not fully deploy, resulted in weak signal.25 The capable ground stations were used to execute uplink commands to the satellite and turn on the radiation experiments, initiating experiment telemetry downlink at extremely weak power levels.

• CACTUS-1
• CAPE-3
• CP12 (ExoCube-2)
• MiTEE-A
• PICS 1
• PICS 2
• PolarCube
• Prometheus 2.8
• Prometheus 2.11
• Q-PACE
• RadFXSat-2 (Fox-1E)
• TechEdSat-7