Listening To A Flashlight — Lunar Flashlight

In case you’ve been searching for a realistic instance of the usage of GNU Radio, you must take a look at [Daniel Estévez’s] paintings on deciphering telemetry captured from the Lunar Flashlight cubesat. The cubesat is having some bother, however the knowledge in query was once a recording from the day after release. We aren’t positive what it might take to pay attention to it reside, however the 3-minute recording is from a 20-meter antenna at 8.4 GHz.

The flowgraph for GNU Radio isn’t as dangerous as you could suppose, thank you to a few considered reuse of blocks from different initiatives to do one of the most deciphering. The modulation is PCM/PM/bi-phase-L. Nominally, the rate is meant to be 48,000 baud, however [Daniel] measured 48,077.

Spacecraft telemetry steadily makes use of the CCSDS (Consultative Committee for Area Knowledge Techniques) usual, and the encoding fits the usual. One oddity is that halfway during the recording, the provider frequency jumps over 120 kHz. [Daniel] speculates that the satellite tv for pc was once correcting its frequency to fasten to an uplink provider from a flooring station.

As soon as the information is unpacked, it’s important to interpret it, and [Daniel] does a just right task the usage of Jupyter. He doesn’t know all the layout of the entire telemetry, however he makes some assumptions that appear sound. We need to surprise how the analytics examine with JPL’s legit flooring station.

The final time we checked in with Daniel, he did the similar trick for Voyager I. If you wish to have to take a look at GNU Radio — despite the fact that you don’t have any radio {hardware} — take a look at our advent.

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