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gut-space / satnogs

The goal of this project is to create a functional satellite ground station, able to receive VHF transmissions from NOAA sats and more!
https://aquarius.klub.com.pl
MIT License
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Experiment with LRPT reception and decoding #33

Closed tomaszmrugalski closed 4 years ago

tomaszmrugalski commented 4 years ago

Right now we're only able to decode APT transmission, which is a 60s technology being used by only 3 NOAA sats and it is being retired. Newer sats (e.g. NOAA-20) no longer use APT. Our current hardware should allow us to receive LRPT transmissions.

According to wikipedia, Metop and NPOESS use LRPT. Metor 2-M use LRPT, too. We should do some manual experiments and see how tricky it is to receive such transmissions.

fivitti commented 4 years ago

Decoding Meteor-M 2 with QPSK modulation is ready.

We receive signal on 137.1MHz and next demodulate it using medet and next retrieve imagery using meteor-decoder. We compose RGB image from channels 68, 65 and 64 channels.

I notice that QPSK requires better signal than APT. If maximal elevation is less then 20 degrees then nothing is decoded.

fivitti commented 4 years ago

Next step: OQPSK modulation in Meteor-M2 2.

fivitti commented 4 years ago

137MHz LRPT transmission is no longer available. I stop works on METEOR-M2 2 recipe.

I keep the ready recipe in MR #50 .

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