Tag Archives: L-Band

AERO-I 600 Baud GMSK

Currently there are 9 AERO-I 600 Baud GMSK channels on POR. Quite a bit of ACARS and CPDLC traffic along with the usual Call Management signaling units. These signals are huge as you can see from the “tightness” of the … Continue reading

Posted in Inmarsat, Projects Tagged

Aero Crypto Calls

Finally found an Aero H/H+ call that was encrypted. Supported crypto services on Aero are US-STU-III (Secure Telephone Unit), STE (Secure Terminal Equipment), FNBDT (Future Narrow Band Digital Terminal). Not clear which service this actually is but I suspect it’s … Continue reading

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Fleet Tracking on Inmarsat 4F3

Most of the popular Inmarsat activity is associated with ships and planes in AOR-E, AOR-W, POR and IOR. There is an Inmarsat satellite called 4F3 parked at 98W that gives CONUS coverage. This satellite is inclined and so does move … Continue reading

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New Inmarsat Aero-H and H+ Decoder in Development

Another new decoder project is in the works. This is another Multi-Channel decoder for Aero but instead of just ACARS and CPDLC it does AMBE and LPC voice decode. The screenshot below shows call logging status output from the prototype … Continue reading

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Inmarsat Aero-P ACARS Multi-Channel Decoder

Inmarsat Aero-P includes an ACARS service for airlines to use while transiting the various ocean regions. This is much more reliable than HF ACARS. Inmarsat hosts 3-4 Aero-P control channels on L-Band for each ocean region. Each control channel is … Continue reading

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Multi-Channel Inmarsat-C Decoder

Below is graphical overview of Marine-C, an Ethernet based Multi-Channel Inmarsat-C decoder. The decoder is able to simultaneous decode up to 12 channels and therefore can cover an entire ocean region with this single application. The decoder monitors all LES … Continue reading

Posted in Inmarsat, Projects Tagged

NOAA HRPT Weather Satellites

There are some nice wide HRPT signals coming from NOAA 15, 18 and 19 (others too, but these are the ones I looked at today). NOAA 15, 18 and 19 are LEO satellites and therefore require real time tracking. Since … Continue reading

Posted in SATCOM Tagged

Inmarsat STD-C

Inmarsat STD-C is a data or message-based system used mostly by maritime operators. An Inmarsat C terminal transmits and received on L-Band to various geosynchronous satellites that service each major ocean region (POR, IOR, AOR-E, AOR-W). The information rate is … Continue reading

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Inmarsat FAX

Inmarsat STD-B service is still active, even after all these years. On STD-B you will find voice, data and fax services Here are a couple of examples of recently received faxes via Inmarsat 3F3 Pacific Ocean Region (POR) at 178°. … Continue reading

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Good Friday Sonde Hunt

Another great day for Sonde Recovery here in sunny California. The winds are good, the weather is nice and the sun is still up at landing time giving plenty of light. This Sonde was originally predicted to land near Rancho … Continue reading

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