SARAL decoding

[N6RFM]

Hi Dani and gr-satellites users! I'm trying to decode SARAL NORAD 39086. The telemetry format is listed as BPSK PMT-A3, 800 baud. I've created a satyaml file with the following parameters, but have not had any success.

name: SARAL
alternative_names:

• CVJK-7644-2588-4230-2659
  norad: 39086
  data:
  &tlm Telemetry:
  telemetry: ax25
  transmitters:
  800k BPSK downlink:
  frequency: 465.988e+6
  modulation: BPSK
  baudrate: 800
  framing: AX.25 G3RUH
  data:
  • *tlm
    800k BPSK downlink:
    frequency: 465.988e+6
    modulation: BPSK
    baudrate: 800
    framing: AX.25
    data:
  • *tlm

A 120mb IQ file may be found here. 50,000 sps. https://mega.nz/file/CtlV1Kyb#XJnTLxaSphUGbJ2_KTTpGb9FUSERukqKcEicvhPYFsc
Any suggestions or advice would be appreciated.

Thanks!
Bob N6RFM

[daniestevez]

Hi Bob,

From a quick look this 465.988 MHz transmitter is something used to relay data from ocean buoys. This PMT-A3 protocol is not something currently supported by gr-satellites, and a custom deframer for it would be needed.

[N6RFM]

Thanks Dani. Indeed an esoteric format. Some are claiming "decodes" using a Satnogs decoder. I'll try to get some specifics. In any case, not a driver for a new deframer . Best, Bob