The Astrocast satellite’s beacon includes in phase I:
• A Pseudo Random Binary Sequence (PRBS) that can be used for ranging
• GNSS coordinates and speed vector
• Telemetry data including selected on-board parameters and measurements
A dashboard prototype for demodulating and decoding beacon data is in preparation.
Telemetry definitions are on the Telemetry page.
The FX.25 extension to AX.25 implements a Forward Error Correction (FEC) “wrapper” around a standard AX.25 packet. The FX.25 wrapper is designed to supplement the existing AX.25 infrastructure without displacing it. The FX.25 signal structure allows reception with a standard AX.25 receiver, albeit without the benefit of the FEC correction functions. An AX.25 receiver interprets the additional FEC information as channel noise. The FX.25 protocol is fully described in [FX.25 – Forward Error Correction Extension to AX.25 Link Protocol For Amateur Packet Radio]; the AX.25 protocol is fully described in [AX.25 Link Access Protocol for Amateur Packet Radio, Version 2.2, Revision July 1998].
This information is preliminary and subject to change. 05-DEC-2018 (ARK)