A Minimal LRIT GOES Receiver(pietern.github.io)
pietern.github.io
A Minimal LRIT GOES Receiver
https://pietern.github.io/goestools/guides/minimal_receiver.html
21 comments
Very cool, having some of the parts already, I'd love to build one of these.
A couple (unrelated) questions:
1) GOES receives data from remote terrestrial weather stations too, right?[1] Is that aggregated and rebroadcast in a way we can receive it?
2) Is data from MODIS available similarly to GOES?
[1] https://ftsinc.com/fire-weather/products/axiom-dataloggers/a...
A couple (unrelated) questions:
1) GOES receives data from remote terrestrial weather stations too, right?[1] Is that aggregated and rebroadcast in a way we can receive it?
2) Is data from MODIS available similarly to GOES?
[1] https://ftsinc.com/fire-weather/products/axiom-dataloggers/a...
Great, if you end up building one, keep us updated (here or on Twitter).
1) Yes, this is DCS (Data Collection System) data. It's a very low bandwidth signal (300 or 1200 baud) that ground stations uplink to GOES on UHF. I found there are about 20k separate transmitters in some asset database I once found somewhere. Every one (or the set that's still active) transmits a tiny packet every N minutes (some every minute, others every 30 minutes). This data is also broadcast as part of the LRIT (GOES-15) and HRIT (GOES-16 and GOES-17) streams. There is no processing for this data in the goestools package yet, but you can get the originals and walk over the data. When I last looked at it, the format looked different per receiver, it is possible this is a per-vendor type of thing. Anyway, yes, you can get a copy of this data with the receiver described in the OP guide. See https://github.com/pietern/goestools/issues/11 for some more links.
2) AFAICT MODIS is a product derived from the Aqua and Terra satellites. Both are polar orbiting sats. You can look them up here https://www.wmo-sat.info/oscar/satellites/view/81 and it looks like they don't pack a "direct readout" transmitter, so you wouldn't be able to receive anything directly yourself. Compare this to the page for GOES-16 at https://www.wmo-sat.info/oscar/satellites/view/152 and you see there are a bunch of frequencies with details listed.
1) Yes, this is DCS (Data Collection System) data. It's a very low bandwidth signal (300 or 1200 baud) that ground stations uplink to GOES on UHF. I found there are about 20k separate transmitters in some asset database I once found somewhere. Every one (or the set that's still active) transmits a tiny packet every N minutes (some every minute, others every 30 minutes). This data is also broadcast as part of the LRIT (GOES-15) and HRIT (GOES-16 and GOES-17) streams. There is no processing for this data in the goestools package yet, but you can get the originals and walk over the data. When I last looked at it, the format looked different per receiver, it is possible this is a per-vendor type of thing. Anyway, yes, you can get a copy of this data with the receiver described in the OP guide. See https://github.com/pietern/goestools/issues/11 for some more links.
2) AFAICT MODIS is a product derived from the Aqua and Terra satellites. Both are polar orbiting sats. You can look them up here https://www.wmo-sat.info/oscar/satellites/view/81 and it looks like they don't pack a "direct readout" transmitter, so you wouldn't be able to receive anything directly yourself. Compare this to the page for GOES-16 at https://www.wmo-sat.info/oscar/satellites/view/152 and you see there are a bunch of frequencies with details listed.
This guide is what got me diving into the world of software defined radio and telecommunications in general. Building this thing has been one of the most rewarding side projects. It really makes you appreciate how many interesting technologies and ideas are there between "the electromagnetic spectrum" and "bits per second".
That is awesome to hear! Building this has been a fun side project and I'm happy to hear it sparked interest for you as well.
So GOES looks to be an imagery satellite, right? And LRIT is some aspect of it's method of communication?
A few explanatory words in the title here, at the beginning of the article would really help. I'm surprised it made first page without them. The author's work is rather cool, though!
A few explanatory words in the title here, at the beginning of the article would really help. I'm surprised it made first page without them. The author's work is rather cool, though!
[GOES-R/GOES-16](https://en.wikipedia.org/wiki/GOES-16) as well as [GOES-S/GOES-17](https://en.wikipedia.org/wiki/GOES-17) are geostationary weather satellites operated by the NOAA.
They broadcast some of their imagery using a format they call LRIT or HRIT (High Rate Information Transmission). You can follow this guide to build a receiver using inexpensive components to tap into that stream.
They broadcast some of their imagery using a format they call LRIT or HRIT (High Rate Information Transmission). You can follow this guide to build a receiver using inexpensive components to tap into that stream.
Sorry, I deeplinked to a part of the docs that doesn't necessarily put everything in context. Mostly I thought the library and hardware setup are really cool, and that Earth imagery is spectacular
Is it possible to receive Solar Ultraviolet Imager (SUVI) images? Didn't find it in the documentation.
It's not. The SUVI data is not broadcast on the HRIT feed, only on the GRB (GOES ReBroadcast) feed. Receiving GRB requires more effort: minimum 10ft dish, dual circular polarized feed, DVB-S2 demodulator, and different software. Never tried this, but would make for a fun project.
Is the near-realite GOES imagery available to download over the internet?
Recently I've been looking for a way to download near-realtime Meteosat imagery. I thought, ok, I'll just download it from their web server. Turns out, you have to use a satellite antenna, receiver and buy commercial software... WTH? This is ridiculous in the 21th century. Why not put the imagery on the internet, for free?
Recently I've been looking for a way to download near-realtime Meteosat imagery. I thought, ok, I'll just download it from their web server. Turns out, you have to use a satellite antenna, receiver and buy commercial software... WTH? This is ridiculous in the 21th century. Why not put the imagery on the internet, for free?
Yes, there are multiple interfaces.
This is a nice interactive one: http://rammb-slider.cira.colostate.edu/?sat=goes-16.
There is also an S3 bucket where you can find all data as soon as it is available: https://registry.opendata.aws/noaa-goes/.
But the fun part is receiving it in your backyard, of course ;)
This is a nice interactive one: http://rammb-slider.cira.colostate.edu/?sat=goes-16.
There is also an S3 bucket where you can find all data as soon as it is available: https://registry.opendata.aws/noaa-goes/.
But the fun part is receiving it in your backyard, of course ;)
Thanks! The S3 bucket is how it should be done.
NOAA has GOES and Meteosat imagery on their website. Meteosat is updated every 6 hours or so, GOES imagery is 15-30 minutes old depending on which image you look at
I wonder what a flat-earther would say about this backyard satellite photography example
Flat-earthers are fascinating. As long as they are not dangerous to themselves and others they are a good subject to study on how brainwashing, paranoia, and reality bubbles work. Also I wonder if some of them are secretly trolls. They don't believe it, but they spread it around to try to get others to believe just for fun. Then they also got a nice "mark" that's ripe for other cons and possibly to profit from ("send me PayPal money to buy this super secret flat Earth detector for $500"). I imagine their community is a goldmine for con-artists...
About nine years ago I found out a friend of mine was a "flat-earther" online. He was very much under the impression that it was mostly an insincere and sarcastic group of people mostly trying to trick people that they actually believe this.
Today I'm not sure if 1. He was wrong about the movement. 2. They succeeded in convincing me and most of us they believe more than they do. 3. They convinced and attracted people and they actually on average do believe that the earth is flat.
Today I'm not sure if 1. He was wrong about the movement. 2. They succeeded in convincing me and most of us they believe more than they do. 3. They convinced and attracted people and they actually on average do believe that the earth is flat.
> Today I'm not sure if 1...2 or 3...
Yeah! That's exactly what's fascinating about it.
I've met a contrails believer and, sadly, I was sure they actually believe it. But flat earthers are in a whole separate category where it is not clear if they are just trolling everyone. Your 3. is interesting at first they might take it up as a joke but then someone out there in the "community" is a better troll, and makes up a more convincing "evidence" and before they know some of the trolls start believing.
Yeah! That's exactly what's fascinating about it.
I've met a contrails believer and, sadly, I was sure they actually believe it. But flat earthers are in a whole separate category where it is not clear if they are just trolling everyone. Your 3. is interesting at first they might take it up as a joke but then someone out there in the "community" is a better troll, and makes up a more convincing "evidence" and before they know some of the trolls start believing.
I believe at this point the number of ironic/trolling flat earthers greatly outnumber the genuine ones. It has reached meme status.
How many photos do these satellites take/send per day?
Depends on the mode the satellite is operating in. Typically: a full disk image every 15 minutes, the continental USA every 5 minutes, and two selected "mesoscale" regions (they will move around based on interesting events) every minute or even 30 seconds. Not all these products are relayed through this downlink though. On HRIT you'll find a full disk image across 7 different spectral bands every 30 minutes, and mesoscale images across 3 different spectral bands every 15 minutes.
Next to this data, it also contains relayed images from GOES-15 (GOES-West), Himawari-8, EMWIN data, and NWS forecasts and plots.
Next to this data, it also contains relayed images from GOES-15 (GOES-West), Himawari-8, EMWIN data, and NWS forecasts and plots.
Also beware that the guide is a little out of date:
1) the listed antenna is no longer available, but there are comparable ones for comparable or lower price, and
2) the SAWBird has been generally available for a couple of weeks.