MultiPSK is a signals decoding program with many available decoders to choose from. It is also able to directly connect to the RTL-SDR, or be used via a virtual audio cable. The latest version now allows for decoding of Orbcomm satellites which transmit at around 137 MHz. While it is not possible to decode the encrypted messages, it is still possible to decode pieces of telemetry data from the satellites.
This system has been developed by the ORBCOMM society which disposes of a constellation of about 28 active LEO (“Low Earth Orbit”) satellites, transmitting between 137.2 and 137.8 MHz (+/- 2.5 KHz maximum of Doppler shift).
This system permits:
This mode is available for licencied copies, only (otherwise, the decoding is stopped after 5 minutes).
- to handle messages (encrypted) from ground users
(ships, trucks, oil wells…) until other ground users, through the ORBCOMM satellites, the cover being worldwide. These frames are decoded by Multipsk but not deciphered.
- to broadcast identification, frequencies, position and orbital elements pieces of information, not encrypted. These frames are decoded and interpreted by Multipsk.
Decoding Orbcomm satellites with MULTIPSK