AirSpy working with Inmarsat Decoder

My new AirSpy SDR arrived last week. The goal this weekend was to make a small application to stream the IQ over Ethernet and then test it with one of the Inmarsat decoders that I have previously developed.

AirSpy SDR.

AirSpy SDR.

The API is very similar to the HackRF One and so it did not take long to get the streaming to work. The AirSpy currently supports either 10MSPS or 2.5MSPS. I choose to work with 2.5MSPS as I will need to decimate it even at that rate.

Here is the small application that runs on the host machine where the AirSpy is plugged into USB.

AirSpy Streamer Application.

AirSpy Streamer Application.

This application will take the IQ samples at 2.5MSPS and then decimate by 8 to give 312.5KSPS. This is then sent over Ethernet using UDP. The decoder can then be located anywhere on the network, including the host machine (loopback). Below is the received L-Band spectrum after decimation as received by the decoder.

IQ Stream from AirSpy.

IQ Stream from AirSpy.

Here is the main decoder log window showing various events along with notification of any messages written to disk.

Decoder status console.

Decoder status console.

Below are the two decoder windows showing real time status.

Real time decoder status.

Real time decoder status.

And finally the overall SDR/Message status and statistics.

SDR and message statistics.

SDR and message statistics.

The AirSpy is performing very well and decoder has been running 2 channels for 24 hours now without any frame loss or disruptions. Excellent performance. I will be placing an order for another one this week for another project I have in mind.

Category(s): Inmarsat, Projects
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6 Responses to AirSpy working with Inmarsat Decoder

    Glenn finney says:

    Very nice set up with an AOR 2300. Do you have a mobile set up for HF or VHF?

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